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Vertebrate mineralized tissues, present in bones, teeth and scales, have complex 3D hierarchical structures. As more of these tissues are characterized in 3D using mainly FIB SEM at a resolution that reveals the mineralized collagen fibrils and their organization into collagen fibril bundles, highly complex and diverse structures are being revealed. In this perspective we propose an approach to analyzing these tissues based on the presence of modular structures: material textures, pore shapes and sizes, as well as extents of mineralization. This modular approach is complimentary to the widely used hierarchical approach for describing these mineralized tissues. We present a series of case studies that show how some of the same structural modules can be found in different mineralized tissues, including in bone, dentin and scales. The organizations in 3D of the various structural modules in different tissues may differ. This approach facilitates the framing of basic questions such as: are the spatial relations between modular structures the same or similar in different mineralized tissues? Do tissues with similar sets of modules carry out similar functions or can similar functions be carried out using a different set of modular structures? Do mineralized tissues with similar sets of modules have a common developmental or evolutionary pathway? STATEMENT OF SIGNIFICANCE: 3D organization studies of diverse vertebrate mineralized tissues are revealing detailed, but often confusing details about the material textures, the arrangements of pores and differences in the extent of mineralization within a tissue. The widely used hierarchical scheme for describing such organizations does not adequately provide a basis for comparing these tissues, or addressing issues such as structural components thought to be characteristic of bone, being present in dermal tissues and so on. The classification scheme we present is based on identifying structural components within a tissue that can then be systematically compared to other vertebrate mineralized tissues. We anticipate that this classification approach will provide insights into structure-function relations, as well as the evolution of these tissues., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.)

Phacotus lenticularis is a freshwater unicellular green alga that forms lens-shaped calcitic shells around the cell. We documented P. lenticularis biomineralization pathways in live daughter cells while still within the reproductive complex, using scanning confocal microscopy and after vitrification using cryo-scanning electron microscopy (cryo-SEM). We show that some or all of the calcium ions required for mineral formation enter the cell through endocytosis, as inferred from the uptake of calcein fluorescent dye. Ions first concentrate inside intracellular vesicles to form small crystals that were detected by birefringence, reflectance, and cryo-SEM of cells in near-native, hydrated state. The crystals later exit the cell and build up the lens-shaped shell. The small crystals first cover the outer lorica surface and later fuse to form a thin continuous shell. This is most likely followed by a second shell maturation phase in which the shell undergoes thickening and crystal reorganization. Crystal assembly within the confined protected volume of the reproduction complex allows controlled shell formation outside the daughter cell. Only two other unicellular marine calcifiers, coccolithophores and miliolid foraminifera, are known to perform intracellular crystal formation. STATEMENT OF SIGNIFICANCE: Calcium carbonate (CaCO 3 ) deposition in aquatic environments is a major component of the global carbon cycle, which determines the CO 2 content of the atmosphere. In freshwater ecosystems, the green alga Phacotus lenticularis is considered the main contributor of autochthonous calcite precipitation and the only algal species known to form its shell through a controlled process. The chemical and ecological effects of P. lenticularis are intensively investigated, but our understanding of its shell formation is limited. We used advanced confocal laser scanning microscopy and cryo-scanning electron microscopy (cryo-SEM) to provide new insights into mineral formation and trafficking in the calcifying P. lenticularis cells., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.)

JNJ-10450232 (NTM-006) is a new molecular entity that is structurally related to acetaminophen. A comprehensive non-clinical safety program was conducted to support first-in-human and clinical efficacy studies based on preclinical data suggesting that the compound has comparable or enhanced antinociceptive and antipyretic efficacy without causing hepatotoxicity at supratherapeutic doses. No hepatic toxicity was noted in a mouse model sensitive to acetaminophen hepatotoxicity or in rats, dogs, and non-human primates in 28-day repeat dose toxicity studies at and above doses/exposures at which acetaminophen is known to cause hepatotoxicity. In the 28-day toxicity studies, all treatment-related findings were monitorable and reversible. Methemoglobinemia, which was observed in dogs and to a lesser extent in rats, is also observed with acetaminophen. This finding is considered not relevant to humans due to species differences in metabolism. Thyroid hypertrophy and hyperplasia were also observed in dogs and were shown to be a consequence of a species-specific UGT induction also demonstrated with increased thyroid hormone metabolism. Indirect bilirubin elevation was observed in rats as a result of UGT1A1 Inhibition. JNJ-10450232 (NTM-006) had no toxicologically relevant findings in safety pharmacology or genotoxicity studies. Together, these data supported progressing into safety and efficacy studies in humans., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Johnson & Johnson employed all authors at the time of the study, and each author has owned, or currently owns, Johnson & Johnson stock., (Copyright © 2023. Published by Elsevier Inc.)

During spicule formation in sea urchin larvae, calcium ions translocate within the primary mesenchymal cells (PMCs) from endocytosed seawater vacuoles to various organelles and vesicles where they accumulate, and subsequently precipitate. During this process, calcium ions are concentrated by more than three orders of magnitude, while other abundant ions (Na, Mg) must be removed. To obtain information about the overall ion composition in the vesicles, we used quantitative cryo-SEM-EDS and cryo-STEM-EDS analyzes. For cryo-STEM-EDS, thin (500 nm) frozen hydrated lamellae of PMCs were fabricated using cryo-focused ion beam-SEM. The lamellae were then loaded into a cryo-TEM, imaged and the ion composition of electron dense bodies was measured. Analyzes performed on 18 Ca-rich particles/particle clusters from 6 cells contained Ca, Na, Mg, S and P in different ratios. Surprisingly, all the Ca-rich particles contained P in amounts up to almost 1:1 of Ca. These cryo-STEM-EDS results were qualitatively confirmed by cryo-SEM-EDS analyzes of 310 vesicles, performed on high pressure frozen and cryo-planed samples. We discuss the advantages and limitations of the two techniques, and their potential applicability, especially to study ion transport pathways and ion trafficking in cells involved in mineralization. STATEMENT OF SIGNIFICANCE: The 'inorganic side of life', encompassing ion trafficking and ion storage in soft tissues of organisms, is a generally overlooked problem. Addressing such a problem becomes possible through the application of innovative techniques, performed in cryogenic conditions, which preserve the tissues in quasi-physiological state. We developed here a set of analytical tools, cryo-SEM-EDS, and cryo-STEM-EDS, which allow reconstructing the ion composition inside vesicles in sea urchin larval cells, on their way to deposit mineral in the skeletons. The techniques are complex, and we evaluate here the advantages and disadvantages of each technique. The methodologies that we are developing here can be applied to other cells and other pathways as well, eventually leading to quantitative elemental analyzes of tissues under cryogenic conditions., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.)

Background: Although the publication of randomized clinical trials defining the benefit of carotid endarterectomy (CEA) for asymptomatic carotid stenosis, medical management of carotid stenosis has changed significantly. With antiplatelet agents and statins, some question whether these trials are still relevant, suggesting that asymptomatic patients with >70% internal carotid artery (ICA) stenosis may do better with medial management alone, lessening the need for CEA and carotid stenting. The Vascular Quality Initiative (VQI) registry has shown that there are wide practice variations regarding the degree of stenosis that prompts surgical intervention but there are few reports of outcomes in patients who do not undergo intervention. We sought to determine the clinical outcomes of the >70% carotid stenosis patients who are treated with medical management alone at our institution., Methods: We identified all patients with ICA stenosis >70% based on hemodynamic consensus criteria (peak systolic velocity >230 cm/s) in our peripheral vascular laboratory from January 2013 through December 2016. With a retrospective chart review, demographics, comorbid conditions, medications, radiographic studies, clinical follow-up, interventions, and outcomes at 2 years were included. Descriptive statistics were used to define these variables., Results: One hundred and seventy three patients were identified with medically managed asymptomatic >70% ICA stenosis based on hemodynamic criteria on duplex ultrasound. The mean age was 67.5 years, 49% were male, 64% were White, 14% were Black, 13% race was undisclosed, 89% were prescribed antiplatelet therapy, 85% were prescribed a statin, and 60% had hypertension controlled to <140/90. Twenty patients (11.5%) experienced a cerebrovascular event during the 2-year study period. There were eight patients with transient ischemic attack, 10 with ipsilateral strokes, and 2 with strokes in unrelated territories., Conclusions: Despite good adherence to current recommendations for medical therapy, patients at our institution are developing symptomatic carotid disease at a rate similar to that reported in historical clinical trials. These data supports the concept that advances in medical management have not resulted in reduced stroke rates in asymptomatic patients with high-grade carotid stenosis at a large academic institution located in the southeastern United States. CEA and stenting provide a significant risk reduction and should be considered more often in this patient population., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Introduction: The objective of this manuscript is to outline the process involved in the development and validation of a survey that is optimal for assessing the impact of a substance use disorder (SUD) elective course., Methods: Face validation was performed once the initial survey was developed. Additionally, field validation was performed by surveying a small population of pharmacy students enrolled in the elective course. Non-parametric chi-square test and factor analysis were performed to analyze survey results and measure survey validity, while Cronbach alpha (CA) was performed to measure reliability., Results: Student survey responses showed a significance of P < .05 using one sample chi-square test for statements 1, 5, 6, 7, 8, 11, 12, 13, and 15. Factor analysis identified five factors; however, only three factors were identified as having good correlation. Factor 1 related to students' beliefs about patients with SUD, factor 2 related to attitudes about patients with SUD, and factor 3 related to beliefs about SUD. Factors 1, 2, and 3 have a calculated CA > 0.7, indicating strong internal consistency and reliability., Conclusions: Some of the original statements loaded as expected and assessed the impact of the course in shaping students' beliefs and attitudes regarding SUD. However, some statements did not load as expected, and the survey was modified in order to better assess the desired endpoints., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Background: The World Symposium on Pulmonary Hypertension (WSPH) in 2018 recommended new definitions of pulmonary hypertension (PH). We investigated the impact of the updated definition on prevalence of PH due to left heart disease (PH-LHD)., Methods: The data of right heart catheterizations in patients with suspected PH-LHD between January 2008 and July 2015 was retrospectively analyzed applying different definitions. The number of patients diagnosed by the updated WSPH hemodynamic criteria of a mean pulmonary artery pressure (mPAP) > 20 mmHg was compared to the number of patients using mPAP ≥ 25 mmHg. The differentiation between patients with isolated post-capillary (Ipc) and combined post-capillary and pre-capillary (Cpc) PH was analyzed comparing the ESC/ERS guidelines, the recommendation of Cologne Consensus Conference (CCC) and WSPH., Results: Of the 726 patients with a suspected PH, 58 patients met the diagnostic criteria of the ESC/ERS guidelines for PH-LHD with 32.8% Ipc-cases, 34.4% Cpc-PH-cases and 32.8% unclassifiable cases. Overall, 58 patients were diagnosed by the CCC criteria, with 34.5% classified as Cpc-PH and 65.5% as Icp-PH. Using the criteria of WSPH, the number of PH-LHD rose by one patient. According to the new definition, 64.4% of the patients were classified as Cpc-PH and had a significantly higher right to left atrial area (RA/LA) ratio than Ipc-PH patients., Conclusion: Applying the new recommendation, the number of diagnosed patients with PH-LHD increases marginally. There is, however, a relevant shift in the number of Cpc-PH cases. An elevated RA/LA ratio might help to identify patients for invasive diagnostic work-up., Competing Interests: Declaration of competing interest Dr. Pfeuffer-Jovic reports fees for travel/accommodation from Actelion, Boehringer Ingelheim, Novartis and OMT, outside the submitted work. Simon Weiner has nothing to disclose. Prof. Dr. Wilkens has received personal fees for lectures and/or advisory board activities from Actelion, Janssen, Bayer Healthcare, Boehringer Ingelheim, GSK, MSD, Pfizer and Roche. Delia Schmitt has nothing to disclose. Prof. Dr. Frantz got support from the BMBF, Abiomed, Amgen, Akzea, AstraZeneca, Bayer, Berlin-Chemie, Braun, Bristol-Myers Squibb, Boehringer, Daiichi Sankyo, MSD, Novartis, Pfizer, Sanofi-Aventis, Servier, Siemens, Zoll. PD Dr. Held reports grants from Actelion, honoraria for lectures from Actelion, Bayer HealthCare, Berlin Chemie, Boehringer Ingelheim, GSK, Novartis, Pfizer, honoraria for advisory board activities from Actelion, Bayer HealthCare, GSK, MSD, and participation in clinical trials of Actelion, Bayer HealthCare, GSK, Pfizer, United Therapeutics, outside the submitted work., (Copyright © 2021 Elsevier B.V. All rights reserved.)

The mineralized collagen fibril is the basic building block of bone, and hence is the key to understanding bone structure and function. Here we report imaging of mineralized pig bone samples in 3D using the focused ion beam-scanning electron microscope (FIB-SEM) under conditions that reveal the 67 nm D-banding of mineralized collagen fibrils. We show that in adult pig osteons, the lamellar bone comprises alternating layers with either collagen fibrils predominantly aligned in one direction, and layers in which fibrils are predominantly aligned in two directions. The cement sheath contains thin layers of both these motifs, but its dominant structural component comprises a very complex layer of fibrils predominantly aligned in three or more directions. The degree of mineralization of the cement sheath is comparable to that of the osteon interior. The extent of alignment (dispersion) of the collagen fibrils in the osteonal lamellar bone is significantly higher than in the cement sheath. Canaliculi within the cement sheath are mainly aligned parallel to the cement sheath boundary, whereas in the lamellar bone they are mainly aligned perpendicular to the lamellar boundaries. This study further characterizes the presence of two types of collagen fibril arrangements previously identified in demineralized lamellar bone from other species. The simple sample preparation procedure for mineralized bone and the lower risk of introducing artifacts opens the possibility of using FIB-SEM to study more samples, to obtain automatic quantitative information on collagen fibril organization and to evaluate the degrees of mineralization all in relatively large volumes of bone., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.)

Introduction: Patients with severe COVID-19 can develop ventilator-dependent acute hypoxic respiratory failure (VDAHRF), which is associated with a higher mortality rate. We evaluated the clinical course of hospitalized COVID-19 patients and compared them with the patients who received invasive mechanical ventilation. Characteristics of intubated patients who were successfully weaned from the ventilator were compared with the patients who failed to be extubated or died in the hospital., Objective: To investigate the clinical course of hospitalized COVID-19 patients, and assess the possible predictors of the disease severity leading to VDAHRF., Methods: This is a single-center, retrospective study. The first 129 patients (18 years or older) with COVID-19 admitted to Monmouth Medical Center from March 1st to April 25th, 2020 were included., Results: Out of 129 patients, 23.25% (n = 30) required invasive mechanical ventilation, and of those, six patients were successfully weaned from the ventilator. Multivariable logistic regression analysis showed increased odds of intubation associated with hypoxemia (odds ratio 17.23, 95% CI 5.206-57.088; p < 0.0001), elevated d-dimer by one unit mg/L of FEU (odds ratio 1.515, 95% CI 5.206-57.088; p = 0.0430) and elevated ferritin by one unit ng/ml (odds ratio 1.001, 95% CI 1.000-1.001, p = 0.0051) on admission, adjusted for other covariates., Conclusions: Patients who required invasive mechanical ventilation were more likely to have older age, male gender, coronary artery disease, diabetes, and obesity. The patients who were successfully weaned from the ventilator were more likely to be younger in age, and none of them had heart failure or CAD., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Emergency medicine is a profession that requires good leadership skills. Emergency physicians must be able to instill confidence in both the staff and patients, inspire the best in others, have the enthusiasm to take on a surplus of responsibilities, and maintain calmness during unexpected circumstances. Accordingly, residency program directors look carefully for leadership qualities and potential among their applicants. Although some people do have a predisposition to lead, leadership can be both learned and taught. In this article, we provide medical students with the tools that will help them acquire those qualities and thus make them more desirable by program directors., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Little is known about shell formation of calcareous dinoflagellates, despite the fact that they are one of the major calcifying organisms of the phytoplankton. Here, calcitic cyst formation in two representative members of calcareous dinoflagellates is investigated using cryo-electron microscopy (cryo-SEM and cryo-FIB-SEM) in combination with micro-Raman and infrared spectroscopy. Only calcein-AM and not calcein enters these cells, indicating active uptake of calcium and other divalent cations. Multifunctional vacuoles containing crystalline inclusions are observed, and the crystals are identified as anhydrous guanine in the β-form. The same vacuolar enclosures contain dense magnesium-, calcium-, and phosphorous-rich mineral bodies. These bodies are presumably secreted into the outer matrix where calcite forms. Calcite formation occurs via multiple independent nucleation events, and the different crystals grow with preferred orientation into a dense reticular network that forms the mature calcitic shell. We suggest a biomineralization pathway for calcareous dinoflagellates that includes (1) active uptake of calcium through the membranes, (2) deposition of Mg 2+ - and Ca 2+ -ions inside disordered MgCaP-rich mineral bodies, (3) secretion of these bodies to the inter-membrane space, and (4) Formation and growth of calcite into a dense reticulate network. This study provides new insights into calcium uptake, storage and transport in calcifying dinoflagellates. STATEMENT OF SIGNIFICANCE: Little is known about the shell formation of calcareous dinoflagellates, despite the fact that they are one of the major calcifying organisms of the phytoplankton. We used state-of-the-art cryo-electron microscopy (cryo-SEM and cryo-FIB-SEM) in combination with micro-Raman spectroscopy to provide new insights into mineral formation in calcifying dinoflagellates. To date, intracellular crystalline calcite was assumed to be involved in calcite shell formation. Surprisingly, we identify these crystalline inclusions as anhydrous guanine suggesting that they are not involved in biomineralization. Instead, a key finding is that MgCaP-rich bodies are probably secreted into the outer matrix where the calcite shell is formed. We suggest that these bodies are an essential part of Ca-uptake, -storage and -transport and propose a new biomineralization model., (Copyright © 2019. Published by Elsevier Ltd.)

The bivalve hinge ligament holds the two shells together. The ligament functions as a spring to open the shells after they were closed by the adductor muscle. The ligament is a mineralized tissue that bears no resemblance to any other known tissue. About half the ligament is composed of a protein-rich matrix, and half of long and extremely thin segmented aragonite crystals. Here we study the hinge ligament of the pearl oyster Pinctada fucata. FIB SEM shows that the 3D organization is remarkably ordered. The full sequence of the major protein component contains a continuous segment of 30 repeats of MMMLPD. There is no known homologous protein. Knockdown of this protein prevents crystal formation, demonstrating that the integrity of the matrix is necessary for crystals to form. X-ray diffraction shows that the aragonite crystals are more aligned in the compressed ligament, indicating that the crystals may be actively contributing to the elastic properties. The fusion interphase that joins the ligament to the shell nacre is composed of a prismatic mineralized tissue with a thin organic-rich layer at its center. Nanoindentation of the dry interphase shows that the elastic modulus of the nacre adjacent to the interphase gradually decreases until it approximates that of the interphase. The interphase modulus slightly increases until it matches the ligament. All these observations demonstrate that the ligament shell complex is a remarkable biological tissue that has evolved unique properties that enable bivalves to open their shell effectively innumerable times during the lifetime of the animal. STATEMENT OF SIGNIFICANCE: The hinge ligament shell complex is a unique functioning structural tissue whose elastic properties enable the shell to open without expending energy. Methionine-rich proteins are not known elsewhere raising fundamental questions about secondary and tertiary structures contributing to its elastic properties. The segmented and extremely thin aragonite crystals embedded in this matrix may also have unexpected elastic materials properties as they flex during compression. The structure of the interphase comprises a fascinating biological joint that connects two very different materials. The interphase materials, including the nacre, are graded with respect to elastic modulus so as to approximately match the connecting components. The interphase incorporates a thin organic rich layer that presumably functions as a gasket. This study raises many fundamental questions relevant to the diverse fields of protein chemistry, biomineralization and biological materials., (Copyright © 2019. Published by Elsevier Ltd.)

We investigate the structures and mechanical properties of leaf midribs of Ficus microcarpa and Prunus dulcis, which deposit calcium oxalate crystals, and of Olea europaea midribs which contain no mineral deposits, but do contain lignified fibers. The midrib mechanical performance contributes to the leaf's ability to maintain a flat conformation for light harvesting and to efficiently reconfigure to reduce wind drag. We use a novel approach involving 3D visualization of the vein structure during mechanical load. This involves the use of customized mechanical loading devices that fit inside a microCT chamber. We show that the elastic, compression and torsional moduli of the midribs of leaves from the 3 species examined vary significantly. We also observed different modes of fracture and buckling of the leaves during compression. We assess the contributions of the calcium oxalate crystals to the mechanical and fracture properties. In F. microcarpa midrib linear arrays of calcium oxalate crystals contribute to resisting the bending, in contrast to P. dulcis leaves, where the calcium oxalate crystals do not resist bending. In both F. microcarpa and P. dulcis isolated calcium oxalate crystals enable high torsional compliance. The integrated microCT - mechanical testing approach could be used to investigate the structure-mechanics relationships in other complex biological samples. STATEMENT OF SIGNIFICANCE: Leaves need to maintain a flat conformation for light harvesting, but they also need to efficiently reconfigure to reduce wind drag. The leaf central vein (midrib) is a key structural component for leaf mechanicss. 3D visualization of the vein structure under mechanical loads showed that veins can be stiffened by reinforcement units composed of calcium oxalates crystals and lignin. The stiffening units can influence the bending and fracture properties of the midribs, and can contribute to determine if buckling will occur during folding. Mineral stiffening elements could be a widespread strategy to reinforce leaf veins and other biological structures. This structural-mechanical approach could be used to study other complex biological samples., (Copyright © 2019 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.)

The International Council for Harmonization (ICH) M7 guideline describes a hazard assessment process for impurities that have the potential to be present in a drug substance or drug product. In the absence of adequate experimental bacterial mutagenicity data, (Q)SAR analysis may be used as a test to predict impurities' DNA reactive (mutagenic) potential. However, in certain situations, (Q)SAR software is unable to generate a positive or negative prediction either because of conflicting information or because the impurity is outside the applicability domain of the model. Such results present challenges in generating an overall mutagenicity prediction and highlight the importance of performing a thorough expert review. The following paper reviews pharmaceutical and regulatory experiences handling such situations. The paper also presents an analysis of proprietary data to help understand the likelihood of misclassifying a mutagenic impurity as non-mutagenic based on different combinations of (Q)SAR results. This information may be taken into consideration when supporting the (Q)SAR results with an expert review, especially when out-of-domain results are generated during a (Q)SAR evaluation., (Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.)

Quantifying ion concentrations and mapping their intracellular distributions at high resolution can provide much insight into the formation of biomaterials. The key to achieving this goal is cryo-fixation, where the biological materials, tissues and associated solutions are rapidly frozen and preserved in a vitreous state. We developed a correlative cryo-Scanning Electron Microscopy (SEM)/Energy Dispersive Spectroscopy (EDS) protocol that provides quantitative elemental analysis correlated with spatial imaging of cryo-immobilized specimens. We report the accuracy and sensitivity of the cryo-EDS method, as well as insights we derive on biomineralization pathways in a foraminifer. Foraminifera are marine protozoans that produce Mg-containing calcitic shells and are major calcifying organisms in the oceans. We use the cryo-SEM/EDS correlative method to characterize unusual Mg and Ca-rich particles in the cytoplasm of a benthic foraminifer. The Mg/Ca ratio of these particles is consistently lower than that of seawater, the source solution for these ions. We infer that these particles are involved in Ca ion supply to the shell. We document the internal structure of the MgCa particles, which in some cases include a separate Si rich core phase. This approach to mapping ion distribution in cryo-preserved specimens may have broad applications to other mineralized biomaterials., Statement of Significance: Ions are an integral part of life, and some ions play fundamental roles in cell metabolism. Determining the concentrations of ions in cells and between cells, as well as their distributions at high resolution can provide valuable insights into ion uptake, storage, functions and the formation of biomaterials. Here we present a new cryo-SEM/EDS protocol that allows the mapping of different ion distributions in solutions and biological samples that have been cryo-preserved. We demonstrate the value of this novel approach by characterizing a novel biogenic mineral phase rich in Mg found in foraminifera, single celled marine organisms. This method has wide applicability in biology, and especially in understanding the formation and function of mineral-containing hard tissues., (Copyright © 2018 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.)

Unlabelled: Trabecular bone is an intricate 3D network of struts and plates. Although the structure-function relations in trabecular bone have been studied since the time of Julius Wolff, controversy still exists regarding the architectural parameters responsible for its stability and resilience. We present a parameter that measures the angle between two connected trabeculae - the Inter-Trabecular Angle (ITA). We studied the ITA values derived from μCT scans of different regions of the proximal femora of 5 individuals of different age and sex. We show that the ITA angle distribution of nodes with 3 connecting trabeculae has a mean close to 120°, nodes with 4 connecting trabeculae has a mean close to 109° and nodes of higher connectivity have mean ITA values around 100°. This tendency to spread the ITAs around geometrically symmetrical motifs is highly conserved. The implication is that the ITAs are optimized such that the smallest amount of material spans the maximal 3D volume, and possibly by so doing trabecular bone might be better adapted to multidirectional loading. We also draw a parallel between trabecular bone and tensegrity structures - where lightweight, resilient and stable tetrahedron-based shapes contribute to strain redistribution amongst all the elements and to collective impact dampening., Statement of Significance: The Inter-Trabecular Angle (ITA) is a new topological parameter of trabecular bone. The ITA characterizes the way trabeculae connect with each other at nodes, regardless of their thickness and shape. The mean ITA value of nodes with 3 trabeculae is close to 120°, of nodes with 4 trabeculae is just below 109°, and the mean ITA of nodes with 5 and more trabeculae is around 100°. Thus the connections of trabeculae trend towards adopting symmetrical shapes. This implies that trabeculae can maximally span 3D space using the minimal amount of material. We draw a parallel between this motif and the concept of tensegrity - an engineering premise to which many living creatures conform at multiple levels of organization., (Copyright © 2016 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.)

The ICH M7 guideline describes a consistent approach to identify, categorize, and control DNA reactive, mutagenic, impurities in pharmaceutical products to limit the potential carcinogenic risk related to such impurities. This paper outlines a series of principles and procedures to consider when generating (Q)SAR assessments aligned with the ICH M7 guideline to be included in a regulatory submission. In the absence of adequate experimental data, the results from two complementary (Q)SAR methodologies may be combined to support an initial hazard classification. This may be followed by an assessment of additional information that serves as the basis for an expert review to support or refute the predictions. This paper elucidates scenarios where additional expert knowledge may be beneficial, what such an expert review may contain, and how the results and accompanying considerations may be documented. Furthermore, the use of these principles and procedures to yield a consistent and robust (Q)SAR-based argument to support impurity qualification for regulatory purposes is described in this manuscript., (Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.)

Fish represent the most diverse and numerous of the vertebrate clades. In contrast to the bones of all tetrapods and evolutionarily primitive fish, many of the evolutionarily more advanced fish have bones that do not contain osteocytes. Here we use a variety of imaging techniques to show that anosteocytic fish bone is composed of a sequence of planar layers containing mainly aligned collagen fibrils, in which the prevailing principal orientation progressively spirals. When the sequence of fibril orientations completes a rotation of around 180°, a thin layer of poorly oriented fibrils is present between it and the next layer. The thick layer of aligned fibrils and the thin layer of non-aligned fibrils constitute a lamella. Although both basic components of mammalian lamellar bone are found here as well, the arrangement is unique, and we therefore call this structure lamellated bone. We further show that the lamellae of anosteocytic fish bone contain an array of dense, small-diameter (1-4 μm) bundles of hypomineralized collagen fibrils that are oriented mostly orthogonal to the lamellar plane. Results of mechanical tests conducted on beams from anosteocytic fish bone and human cortical bone show that the fish bones are less stiff but much tougher than the human bones. We propose that the unique lamellar structure and the orthogonal hypomineralized collagen bundles are responsible for the unusual mechanical properties and mineral distribution in anosteocytic fish bone., (Copyright © 2014 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.)

Bone is a complex hierarchically structured family of materials that includes a network of cells and their interconnected cell processes. New insights into the 3-D structure of various bone materials (mainly rat and human lamellar bone and minipig fibrolamellar bone) were obtained using a focused ion beam electron microscope and the serial surface view method. These studies revealed the presence of two different materials, the major material being the well-known ordered arrays of mineralized collagen fibrils and associated macromolecules, and the minor component being a relatively disordered material composed of individual collagen fibrils with no preferred orientation, with crystals inside and possibly between fibrils, and extensive ground mass. Significantly, the canaliculi and their cell processes are confined within the disordered material. Here we present a new hierarchical scheme for several bone tissue types that incorporates these two materials. The new scheme updates the hierarchical scheme presented by Weiner and Wagner (1998). We discuss the structures at different hierarchical levels with the aim of obtaining further insights into structure-function-related questions, as well as defining some remaining unanswered questions., (Copyright © 2014 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.)

Background: Obesity and diabetes usually co-exist. Obesity surgery seems to offer solutions for both. The objective of this study was to show the effect of obesity surgery on the diabetic profile., Methods: Data on obesity surgery in Germany (2005-2011) were collected from the Institute of Quality Assurance at the research university. Follow-up of the diabetic profile at 1, 2, and up to 6 years after surgery was done., Results: Among 17,670 patients, 5,506 (31.2%) were diabetics. Follow-up was accomplished in 87.4%, 82.5%, and 68.9% of eligible patients at 1, 2, and up to 6 years, respectively, after surgery. Of the study participants, 38.2% were insulin-treated (IT) patients and 61.8% were noninsulin-treated patients (NIT). Of the patients' procedures, 2878 (52.3%) Roux-en-Y gastric bypasses (RYGB), 1711 (31.1%) sleeve gastrectomies (SG), 679 (12.3%) laparoscopic adjustable gastric bands (LAGB), 165 (3%) biliopancreatic diversions with duodenal switch (BPD/DS), and 68 (1.3%) biliopancreatic diversions (BPD) were performed. Female gender percentage and mean body mass index (BMI) were significantly higher in the RYGB and LAGB groups. Mean age was significantly higher in BPD/DS group. At 1 year, remission/improvement (RI) percentage was 83.5%, 82.5%, 67.8%, 93.4%, and 84.8% after RYGB, SG, LAGB, BPD, and BPD/DS, respectively. At 2 years, RI% was 84.9%, 79.5%, 67.7%, 94.5%, and 90.9% after RYGB, SG, LAGB, BPD, and BPD/DS, respectively. At late follow-up, RI% was 83.2%, 59.5%, 58.9%, 100%, and 86.4% after RYGB, SG, LAGB, BPD, and BPD/DS, respectively. IT patients showed insignificantly higher RI% than NIT patients at all follow-up points. Malabsorptive procedures (RYGB, BPD, and BPD/DS) showed a significantly higher RI% than restrictive procedures (LAGB and SG) at late follow-up., Conclusion: Obesity surgery has promising antidiabetic efficacy, especially in IT patients. Malabsorptive procedures show higher, gradually descending, but durable antidiabetic efficacy., (Copyright © 2014 American Society for Bariatric Surgery. Published by Elsevier Inc. All rights reserved.)

With the increasing emphasis on identification and low level control of potentially genotoxic impurities (GTIs), there has been increased use of structure-based assessments including application of computerized models. To date many publications have focused on the ability of computational models, either individually or in combination, to accurately predict the mutagenic effects of a chemical in the Ames assay. Typically, these investigations take large numbers of compounds and use in silico tools to predict their activity with no human interpretation being made. However, this does not reflect how these assessments are conducted in practice across the pharmaceutical industry. Current guidelines indicate that a structural assessment is sufficient to conclude that an impurity is non-mutagenic. To assess how confident we can be in identifying non-mutagenic structures, eight companies were surveyed for their success rate. The Negative Predictive Value (NPV) of the in silico approaches was 94%. When human interpretation of in silico model predictions was conducted, the NPV increased substantially to 99%. The survey illustrates the importance of expert interpretation of in silico predictions. The survey also suggests the use of multiple computational models is not a significant factor in the success of these approaches with respect to NPV., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Background: Results of previous studies support the hypothesis that implantable haemodynamic monitoring systems might reduce rates of hospitalisation in patients with heart failure. We undertook a single-blind trial to assess this approach., Methods: Patients with New York Heart Association (NYHA) class III heart failure, irrespective of the left ventricular ejection fraction, and a previous hospital admission for heart failure were enrolled in 64 centres in the USA. They were randomly assigned by use of a centralised electronic system to management with a wireless implantable haemodynamic monitoring (W-IHM) system (treatment group) or to a control group for at least 6 months. Only patients were masked to their assignment group. In the treatment group, clinicians used daily measurement of pulmonary artery pressures in addition to standard of care versus standard of care alone in the control group. The primary efficacy endpoint was the rate of heart-failure-related hospitalisations at 6 months. The safety endpoints assessed at 6 months were freedom from device-related or system-related complications (DSRC) and freedom from pressure-sensor failures. All analyses were by intention to treat. This trial is registered with ClinicalTrials.gov, number NCT00531661., Findings: In 6 months, 83 heart-failure-related hospitalisations were reported in the treatment group (n=270) compared with 120 in the control group (n=280; rate 0·31 vs 0·44, hazard ratio [HR] 0·70, 95% CI 0·60-0·84, p<0·0001). During the entire follow-up (mean 15 months [SD 7]), the treatment group had a 39% reduction in heart-failure-related hospitalisation compared with the control group (153 vs 253, HR 0·64, 95% CI 0·55-0·75; p<0·0001). Eight patients had DSRC and overall freedom from DSRC was 98·6% (97·3-99·4) compared with a prespecified performance criterion of 80% (p<0·0001); and overall freedom from pressure-sensor failures was 100% (99·3-100·0)., Interpretation: Our results are consistent with, and extend, previous findings by definitively showing a significant and large reduction in hospitalisation for patients with NYHA class III heart failure who were managed with a wireless implantable haemodynamic monitoring system. The addition of information about pulmonary artery pressure to clinical signs and symptoms allows for improved heart failure management., Funding: CardioMEMS., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

According to the 2008 US FDA (draft) and 2006 EMEA guidance documents for genotoxic impurities, an impurity that is positive in an in vitro genotoxicity study, in the absence of in vivo genotoxicity or carcinogenicity data, should be treated as genotoxic and typically controlled to 1.5 microg/day for chronic use. For p-nitrophenol (PNP), existing study results (i.e., positive in vitro clastogenicity in mammalian cells, no information on its in vivo genotoxicity, and negative with respect to carcinogenicity in a dermal mouse study with no confirmation of systemic exposure) indicated that it should be considered genotoxic and exposure as a drug impurity limited. Therefore, to more completely characterize the genotoxic potential of PNP (consistent with the guidance documents), in vivo mouse micronucleus and dermal pharmacokinetic bridging studies were conducted. In the micronucleus study, PNP was negative, demonstrating that the reported in vitro clastogenicity is not present in vivo. In the pharmacokinetic study, PNP was well absorbed dermally, validating the negative dermal carcinogenicity assessment. These results indicate that PNP should be considered a non-genotoxic impurity and, as a drug impurity, a threshold limit of 4 mg/day would be set (per ICH Q3C). This threshold limit is higher than the EPA reference dose (listed in the 2006 Edition of the Drinking Water Standards and Health Advisories), so if present at such levels, the specification limits for PNP should be determined on a case-by-case basis, based on risk-benefit.

Objectives: To develop algorithms for a conversion of disease-specific quality-of-life into health state values for morbidly obese patients before or after bariatric surgery., Methods: A total of 893 patients were enrolled in a prospective cross-sectional multicenter study. In addition to demographic and clinical data, health-related quality-of-life (HRQoL) data were collected using the disease-specific Moorehead-Ardelt II questionnaire (MA-II) and two generic questionnaires, the EuroQoL-5D (EQ-5D) and the Short Form-6D (SF-6D). Multiple regression models were constructed to predict EQ-5D- and SF-6D-based utility values from MA-II scores and additional demographic variables., Results: The mean body mass index was 39.4, and 591 patients (66%) had already undergone surgery. The average EQ-5D and SF-6D scores were 0.830 and 0.699. The MA-IIwas correlated to both utility measures (Spearman's r = 0.677 and 0.741). Goodness-of-fit was highest (R(2) = 0.55 in the validation sample) for the following item-based transformation algorithm: utility (MA-II-based) = 0.4293 + (0.0336 x MA1) + (0.0071 x MA2) + (0.0053 x MA3) + (0.0107 x MA4) + (0.0001 x MA5). This EQ-5D-based mapping algorithm outperformed a similar SF-6D-based algorithm in terms of mean absolute percentage error (P = 0.045)., Conclusions: Because the mapping algorithm estimated utilities with only minor errors, it appears to be a valid method for calculating health state values in cost-utility analyses. The algorithm will help to define the role of bariatric surgery in morbid obesity.

This study examines the question of whether the stiffness (Young's modulus) of secondary osteonal cortical bone is different in compression and tension. Electronic speckle pattern interferometry (ESPI) is used to measure concurrently the compressive and tensile strains in cortical bone beams tested in bending. ESPI is a non-contact method of measuring surface deformations over the entire region of interest of a specimen, tested wet. The measured strain distributions across the beam, and the determination of the location of the neutral axis, demonstrate in a statistically-robust way that the tensile Young's modulus is slightly (6%), but significantly greater than that of the compressive Young's modulus. It is also shown that within a relatively small bone specimen there are considerable variations in the modulus, presumably caused by structural inhomogeneities.

Objective: The purpose of this study was to determine whether fetuses with a congenital heart defect demonstrate changes in cerebrovascular impedance., Study Design: Fetal echocardiograms from January 2001 to May 2005 were reviewed. Cases had sonographically diagnosed congenital heart defects; control subjects were gestational age-matched fetuses with normal echocardiograms. The pulsatility index in the middle cerebral artery was used to measure impedance to cerebral blood flow. Abnormal middle cerebral artery pulsatility index was defined as less than the 5th percentile. Cases were subgrouped into mixing versus nonmixing lesions., Results: Of 142 total fetuses, there were significantly more abnormal middle cerebral artery pulsatility indices in the cases (5/71) than in the control subjects (0/71; P = .023); all abnormal middle cerebral artery pulsatility indices occurred in the fetuses with admixing cardiac lesions., Conclusion: Fetuses with congenital heart defect are significantly more likely to have decreased cerebrovascular impedance. This may represent a marker of cerebral hypoxemia that is due to intracardiac mixing of oxygenated and deoxygenated blood. Theoretically, this hypoxemia may contribute to the cause of abnormal neurologic development in these infants.

Objective: The purpose of this study was to determine the predictive accuracy of a test for neonatal death from pulmonary hypoplasia by measuring changes in fetal pulmonary artery blood flow on room air and during maternal hyperoxygenation., Study Design: Women who were carrying fetuses with congenital anomalies that may cause pulmonary hypoplasia were offered participation in the study as part of a comprehensive fetal echocardiogram. Each fetus at > or =30 weeks of gestation underwent Doppler measurement of the blood flow pattern in the first branch of either the right or the left pulmonary artery before and again during exposure to maternal breathing of 60% oxygen by mask. An increase in the fetal pulmonary blood flow with oxygen (a decrease of > or =20% of the pulsatility index) was considered a reactive test. A change of <20% in the flow pattern during maternal hyperoxygenation was a nonreactive test and suggested pulmonary hypoplasia. The primary outcome for this study was neonatal death from pulmonary hypoplasia., Results: Twenty-nine pregnancies met the criteria for inclusion in our study. Of the 14 fetuses who had a nonreactive hyperoxygenation test, 11 fetuses (79%) died of pulmonary hypoplasia. Of the 15 fetuses who had a reactive hyperoxygenation test, only one fetus (7%) died in the neonatal period. Sensitivity, specificity, and positive and negative predictive values were 92%, 82%, 79%, and 93%, respectively, with an odds ratio of 51 (95% CI, 4.6-560)., Conclusion: Testing fetal pulmonary vascular reactivity with maternal hyperoxygenation is highly predictive of pulmonary hypoplasia. A reactive test predicted 92% of surviving infants; a nonreactive test predicted 79% of fetal deaths from pulmonary hypoplasia.

Background: History of breast cancer has been reported as a risk factor for colorectal cancer in women. In view of the ambiguous nature of existing evidence and the growing interest in targeted colorectal cancer prevention, we sought to quantify this risk., Methods: We used the Surveillance Epidemiology and End Results (SEER) database to estimate risk of colorectal cancer after breast-cancer diagnosis in women with first incident breast cancer between 1974 and 1995. Observed colon and rectal cancer risk was compared with that expected in the general population. We stratified comparisons by age at breast-cancer diagnosis, stage of cancer, ethnic origin of patient, and follow-up time., Findings: Overall, women with previous breast cancer were 5% less likely (95% CI 1-9) to develop colon and 13% less likely (6-19) to develop rectal cancer than women in the general population. Stratified analyses suggested that the risk reductions observed for colon and rectal cancer were most pronounced for women with breast cancer diagnosed after age 65 years, in white women, women with local stage breast cancer, and women diagnosed in the later study years (1990-94)., Interpretations: Breast cancer does not increase subsequent colorectal cancer risk, and reduced risk was seen for certain subgroups of women. Because no biologically plausible endogenous protective factor has been identified, we suggest that reduced risk could stem from an accumulation of exposures that increase breast-cancer frequency but protect against colorectal cancer.

Background/aims: Several reports, especially from Southern Europe, have demonstrated a close association between hepatitis C virus (HCV) infection and mixed cryoglobulinemia. In this study we have analyzed the significance of HCV-related cryoglobulinemia in Germany., Methods: Sera from 79 patients with cryoglobulinemia of type I (n=21), II (n=28) or III (n=30) were investigated for HCV markers. Furthermore, 132 consecutive patients with chronic hepatitis C were studied for the presence of cryoglobulins. Genotypes of HCV were determined according to Simmonds, and HCV-RNA concentrations were measured in patients with and without cryoglobulinemia., Results: In 79 patients with cryoglobulinemia we found anti-HCV antibodies in 17 (22%) and HCV-RNA in 11 patients (14%). HCV antibodies were more frequent in essential (44%) compared to secondary mixed cryoglobulinemia (15%). In 132 patients with chronic HCV infection cryoglobulins were detected in 37 patients (28%), in 21 of them at low levels. Clinical symptoms due to cryoglobulinemia were observed in eight of the 37 patients, severe vasculitis in three patients with high cryocrit-levels and cryoprecipitation at room temperature. HCV genotype 1 and subtype 1b were most prevalent, both in patients with and without cryoglobulinemia, and mean HCV-RNA levels were not different between the two groups. Comparison of HCV-RNA levels in cryoprecipitates, supernatant and native serum suggests binding of HCV-RNA to the cryoprecipitate with different affinity in individual patients., Conclusions: The lower prevalence of HCV-related cryoglobulinemia in our study compared with data from Italy and France suggests a south-north gradient in the prevalence of HCV-associated cryoglobulinemia in Europe.

Cerebrovascular accident (CVA) is a major complication of sickle cell disease. The incidence and mortality of and risk factors for CVA in sickle cell disease patients in the United States have been reported only in small patient samples. The Cooperative Study of Sickle Cell Disease collected clinical data on 4,082 sickle cell disease patients enrolled from 1978 to 1988. Patients were followed for an average of 5.2 +/- 2.0 years. Age-specific prevalence and incidence rates of CVA in patients with the common genotypes of sickle cell disease were determined, and the effects of hematologic and clinical events on the risk of CVA were analyzed. The highest rates of prevalence of CVA (4.01%) and incidence (0.61 per 100 patient-years) were in sickle cell anemia (SS) patients, but CVA occurred in all common genotypes. The incidence of infarctive CVA was lowest in SS patients 20 to 29 years of age and higher in children and older patients. Conversely, the incidence of hemorrhagic stroke in SS patients was highest among patients aged 20 to 29 years. Across all ages the mortality rate was 26% in the 2 weeks after hemorrhagic stroke. No deaths occurred after infarctive stroke. Risk factors for infarctive stroke included prior transient ischemic attack, low steady-state hemoglobin concentration and rate of and recent episode of acute chest syndrome, and elevated systolic blood pressure. Hemorrhagic stroke was associated with low steady-state hemoglobin and high leukocyte count.

Objective: Our purpose was to compare the accuracy of ultrasonographic and manual cervical examinations for the prediction of preterm delivery., Study Design: One hundred two singleton pregnancies at high risk for preterm delivery were followed up prospectively from 14 to 30 weeks with both serial cervical ultrasonography measurements and manual examinations of the length of the cervix. The primary outcome studied was preterm (< 35 weeks) delivery., Results: Excluding six induced preterm deliveries, 96 pregnancies were analyzed. The mean cervical length measured by ultrasonography was 20.6 mm in pregnancies delivered preterm (n = 17) and 31.3 mm in pregnancies delivered at term (n = 79) (p = 0.003); the mean cervical lengths measured by manual examination were 16.1 mm and 18.6 mm in the same preterm and term pregnancies, respectively (not significant). The sixteenth- and twentieth-week ultrasonographic cervical lengths predicted preterm delivery most accurately (p < 0.0005). The 25th percentiles of ultrasonographic (25 mm) and manual (16 mm) cervical lengths showed relative risks for preterm delivery of 4.8 (95% confidence interval 2.1 to 11.1, p = 0.0004) and 2.0 (95% confidence interval 0.5 to 4.7, p = 0.1), respectively; sensitivity, specificity, and positive and negative predictive values were 59%, 85%, 45%, 91%, and 41%, 77%, 28%, and 86%, respectively., Conclusion: Cervical length measured by ultrasonography is a better predictor of preterm delivery than is cervical length measured by manual examination. Cervical ultrasonography in patients at high risk for preterm birth seems to be most predictive of preterm delivery when it is performed between 14 and 22 weeks' gestation.

Objective: Our purpose was to establish normal physiologic parameters in the fetal proximal and distal branch pulmonary arterial vascular impedance during the second half of pregnancy and to analyze relationships between proximal and distal pulmonary arterial blood velocity waveforms., Study Design: In this cross-sectional study 100 uncomplicated singleton pregnancies were studied by pulsed color Doppler techniques between 18 and 41 weeks of gestation (median 30 weeks). Both right and left proximal (immediately after the bifurcation of the main pulmonary artery) and distal (beyond the first bifurcation of the branch pulmonary artery) pulmonary artery blood velocity waveforms were recorded and pulsatility index values were calculated. Peak systolic velocities and time-to-peak-velocity intervals were measured. Time-to-peak-velocity intervals were also analyzed at the level of aortic and pulmonary valves and at the ductus arteriosus. Right and left pulmonary artery diameters and right lung length were measured., Results: In both right and left proximal and distal pulmonary arteries pulsatility index values decreased (p < 0.0001) and the peak systolic velocities (p < 0.003) and time-to-peak-velocity intervals (p < 0.0001) increased during the second half of pregnancy. In the proximal pulmonary arteries the pulsatility index values decreased linearly until 34 to 35 weeks of gestation and in the distal pulmonary arteries until 31 weeks of gestation. Thereafter they remained unchanged. In pulmonary arteries time-to-peak-velocity intervals were shorter (p < 0.01) than at the pulmonary valve level. There were no significant differences between the right or left pulmonary arteries in the pulsatility index values, peak systolic velocities, time-to-peak-velocity intervals, or pulmonary artery diameters. In the proximal pulmonary arteries the pulsatility index values (p < 0.02) and peak systolic velocities (p < 0.0001) were higher and time-to-peak-velocity intervals (p < 0.0001) were longer than in the distal pulmonary arteries. There was a 2.5-fold increase in pulmonary artery diameters and right lung length., Conclusions: Fetal branch pulmonary arterial vascular impedance decreases significantly during the second half of pregnancy. The linear decrease in vascular impedance during the second trimester and in the beginning of the third trimester may be related to the growth of the lung and the increase in the number of resistance vessels. During the latter part of the third trimester pulmonary vascular impedance does not decrease further.

From 1978 to 1988, The Cooperative Study of Sickle Cell Disease observed 3,765 patients with a mean follow-up of 5.3 +/- 2.0 years. One thousand seventy-nine surgical procedures were conducted on 717 patients (77% sickle cell anemia [SS], 14% sickle hemoglobin C disease [SC], 5.7% S beta zero thalassemia, 3% S beta zero + thalassemia). Sixty-nine percent had a single procedure, 21% had two procedures, and the remaining 11% had more than two procedures during the study follow-up. The most frequent procedure was abdominal surgery for cholecystectomy or splenectomy (24% of all surgical procedures, N = 258). Of these, 93% received blood transfusion, and there was no association between preoperative hemoglobin A level and complication rates (except reduction in pain crisis). Overall mortality within 30 days of a surgical procedure was 1.1% (12 deaths after 1,079 surgical procedures). Three deaths were considered to be related to the surgical procedure and/or anesthesia (0.3%). No deaths were reported in patients younger than 14 years of age. Sickle cell diseases (SCD)-related complications after surgery were more frequent in SS patients who received regional compared with general anesthesia (adjusted for risk level of the surgical procedure, patient age, and preoperative transfusion status, P = .058). Non-SCD-related postoperative complications were higher in both SS and SC patients who received regional compared with those who received general anesthesia (P =.095). Perioperative transfusion was associated with a lower rate of SCD-related postoperative complications for SS patients undergoing low-risk procedures (P = .006, adjusted for age and type of anesthesia), with crude rated of 12.9% without transfusion compared with 4.8% with transfusion. In SC patients, preoperative transfusion was beneficial for all surgical risk levels (P = .009). Thus, surgical procedures can be performed safely in patients with SCD.

Within the Cooperative Study of Sickle Cell Disease, 694 infants with confirmed sickle cell disease were enrolled at less than 6 months of age. Information about the nature and frequency of complications was collected prospectively over a 10-year period. Painful crises and acute chest syndrome were the most common sickle cell-related events in homozygous sickle cell anemia (SS), hemoglobin SC disease (SC), and S beta thalassemia patients (overall incidence in SS patients of 32.4 and 24.5 cases per 100 person-years, respectively). Bacteremia occurred most frequently in SS children under 4 years of age and in SC patients less than 2 years of age. The mortality rate was low in this cohort compared with that found in previous reports. Twenty children, all with Hb SS, died (1.1 deaths per 100 person-years among SS patients). Infection, most commonly with Streptococcus pneumoniae and Hemophilus influenzae, caused 11 deaths. Two children died of splenic sequestration, 1 of cerebrovascular accident, and 6 of unclear causes. Two patients underwent cholecystectomies, and 17 underwent splenectomies after one or more splenic sequestration crises. The experience of this cohort should reflect closely the true clinical course of those children with Hb SS and Hb SC disease who are observed in sickle cell centers in the United States.

Objective: Our purpose was to determine the involvement of the female genital tract and its functional consequences on menstrual and sexual aspects in systemic sclerosis., Study Design: Sixty women with systemic sclerosis and 23 age- and disease duration-matched women with either rheumatoid arthritis or systemic lupus erythematosus were surveyed with a comprehensive questionnaire addressing problems before and after disease onset. Fourteen systemic sclerosis patients also had gynecologic evaluations., Results: Vaginal dryness (71%), ulcerations (23%), and dyspareunia (56%) were significantly more frequent in patients with systemic sclerosis after disease onset than before and also in comparison with control subjects. Vaginal tightness and constricted introitus were present in 5 of 60 systemic sclerosis patients. More than half of systemic sclerosis patients reported a decrease in the number (p = 0.04) and intensity (p = 0.02) of orgasms, compared to < 20% of control subjects. The desire and frequency of coitus and the sexual satisfaction index were impaired equally in each group. Skin tightness, reflux-heartburn, and muscle weakness adversely affected sexual relations more in systemic sclerosis than in control subjects. On gynecologic examination 5 of 11 systemic sclerosis patients had small-sized uteri, and 3 of them had early menopause at 29, 38, and 43 years. Seven of 16 (44%) women with systemic sclerosis, compared with 6% of normal women in the United States, attained natural menopause before age 45., Conclusions: Although impairment in various indexes of sexual function occurs in a number of autoimmune diseases, decreased orgasmic function appears to be limited to systemic sclerosis. Vaginal involvement and other systemic sclerosis-related systemic symptoms adversely influence sexual relations. Menstrual abnormalities, including early menopause, affect many patients. Genital tract involvement occurs in a substantial proportion. Prospective longitudinal studies are warranted.

Bone samples from patients suffering from osteogenesis imperfecta (OI) types I, II, III and IV, as well as normal controls, were studied by scanning (SEM) and transmission electron microscopy (TEM). SEM views of normal bone at low magnification show coherent structure, with regular striations due to a lamellar plywood-like arrangement of the mineralized collagen fibrils. Compact lamellar bone was also found in various OI specimens, but in limited disconnected regions separated by open spaces. Furthermore, some OI, but not normal, bones have regions of loose unconnected fibers and others of apparently abnormally dense mineral deposition. High resolution TEM studies of OI bone fragments have served to elucidate the structures of these different textures. There appears to be a substantial, though reduced, proportion of normal lamellar bone even in quite severe OI. However, the regions of loose fibers are largely unmineralized and probably contain abnormal collagen. Other regions are overmineralized, with generally small unorganized apatite crystals deposited onto fibril surfaces or in separate clusters. These structural abnormalities, together with the paucity of normal bone, may explain the fragility of OI bones.

This study investigates the effect of emotional behavior on the masseteric muscle EMG response patterns. Two experimental protocols are utilized: (1) does not elicit emotional behavior (stick chewing) and (2) elicits emotional behavior (hypothalamic stimulation). The Karhunen-Loève transform is used to compute features which exactly represent the correlated patterns of mean-zero observations, with data compression and noise immunity. Using nonparametric tests, it is found that the populations of biting and hissing features are significantly different (p < 0.05), with increased statistical significance as the size of the training set is increased. No statistically significant difference is seen in a test of the two biting populations.

Objective: Our purpose was to determine if cytogenetic discrepancies between fetal blood and amniotic fluid are present in fetuses with prenatally diagnosed diaphragmatic hernia., Study Design: Chromosome analysis was performed on 15 fetuses with prenatally diagnosed diaphragmatic hernia. Fourteen had both amniotic fluid and fetal blood studies. One fetus had an amniocentesis followed by postnatal skin and peripheral lymphocyte chromosome analysis., Results: In one fetus with a normal karyotype on fetal blood, amniotic fluid mosaicism for a supernumerary isochromosome 12p was identified. Another fetus had normal amniotic fluid chromosome analysis but was diagnosed with mosaic isochromosome 12p on skin biopsy after birth. Concordant aneuploidy in both fetal blood and amniocytes was found in five pregnancies (three with trisomy 18, one with an unbalanced translocation, and one with mosaic supernumerary isochromosome 12p). Eight fetuses had normal karyotypes., Conclusion: Because diaphragmatic hernia is a common component of mosaic isochromosome 12p syndrome and this chromosome abnormality is predominantly found in fibroblasts but not lymphocytes, an amniocentesis may be more accurate than fetal blood sampling in defining the true fetal chromosome status when diaphragmatic hernia is detected prenatally.

Objective: Our purpose was to evaluate the effects of chorionic villus sampling on the fetal heart rate, the fetal umbilical artery pulsatility index, and the maternal arcuate artery resistance index., Study Design: M-mode fetal heart rate, pulsed Doppler fetal umbilical artery pulsatility index, and maternal arcuate artery resistance index measurements were obtained before and immediately after chorionic villus sampling in 50 patients and were compared with 50 procedure-free, gestational age--matched controls. Comparisons within groups were performed with paired T tests and mean changes between groups with two-sample T tests, and variance comparisons between groups were performed with F tests., Results: The mean changes (SD) in fetal heart rate, umbilical artery pulsatility index, and arcuate artery resistance index in patients undergoing chorionic villus sampling and in controls were not statistically different from zero or from each other. However, the variance around the mean fetal heart rate change was 17.1 times larger in the chorionic villus sampling group than the control group (F 17.1, degrees of freedom 49,49, p < 0.0001), and the variance around the mean pulsatility index change was 2.7 times larger in the chorionic villus sampling group than in the control group (F 2.7, degrees of freedom 49,49, p = 0.0007). There was no significant difference in mean resistance index change or variance around the mean resistance index change between groups., Conclusion: Chorionic villus sampling induces significant but unpredictable fluctuations in fetal heart rate and umbilical artery pulsatility index but does not affect maternal arcuate artery resistance index.

Objectives: The purpose of this study was to analyze cases in which antenatal improvement of absent fetal umbilical artery end-diastolic velocity was detected and to correlate improvement with perinatal outcome., Study Design: Forty cases of umbilical artery absent end-diastolic velocity in singleton pregnancies were retrospectively reviewed. Maternal characteristics and perinatal outcomes were compared in cases where improvement of end-diastolic velocity was diagnosed and those in which no improvement was detected., Results: Eleven cases of absent end-diastolic velocity showed antenatal improvement and were associated with more advanced gestational age at delivery, longer diagnosis-to-delivery interval, larger birth weights, and a lower incidence of neonatal death than those fetuses without antenatal improvement., Conclusion: Improvement of umbilical artery absent end-diastolic velocity can occur and is associated with improved pregnancy outcome when compared with patients without antenatal improvement of diastolic velocity.

Eighteen pregnancies with nonimmune hydrops fetalis were referred for fetal echocardiography to rule out congenital heart disease. In 14 of these cases, pulsating blood velocities were recorded in the umbilical vein, which in a normal population had a nonpulsatile blood velocity pattern. The four cases without pulsations in the umbilical vein were found to have intrauterine viral infections. In the last 10 cases examined, the umbilical venous pulsations were found to reflect abnormal central venous pulsations during atrial systole suggesting increased fetal central venous pressure. Right ventricular shortening fraction was significantly decreased in the group with umbilical venous pulsations compared with those without (0.18 versus 0.32, p less than 0.05). All the fetuses without venous pulsations survived, but only four of the 14 with pulsations survived (p less than 0.05). The results suggest that blood velocity recordings in the umbilical and central veins of the fetus can give valuable clinical information with regard to the presence of fetal congestive heart failure and differentiate between this physiologic state and other causes of nonimmune hydrops fetalis. This may have implications for fetal diagnostic work-up and prognosis.

Experiences of the control of fowl cholera in large poultry farms in Hungary are reported. A vaccination method combined with sulfaquinoxaline treatment was developed against fowl cholera. Studies were carried out for the determination of the therapeutic and toxic doses of sulfaquinoxaline in fowls experimetnally infected with Pasteurella multocida. Field experiences with Sukvin, a sulfaquinoxaline containing vaccine, against this disease are reported. Sukvin was produced by Phylaxia Serum State Institute, Budapest, Hungary, and has been generally used in that country since 1967.

Prospective pregnancy evaluation through the combined use of a radioimmunoassay (RIA) for the beta-subunit of human chorionic gonadotropin (beta-hCG) and ultrasound during the first 42 days of gestation after ovulation was performed on a population asymptomatic for first-trimester spontaneous abortion. One hundred forty-six ultrasonic observations in 98 pregnancies were made with simultaneous beta-hCG RIA performed in 80 patients. The following landmarks of normal gestational growth were identified: (1) Before 26 days, beta-HCG RIA permits definitive diagnosis of growing trophoblastic tissue, and serial samples allow doubling time computation for prognosis while ultrasound shows a nonspecific increasing decidual response within the uterus; (2) between 26 and 36 days after ovulation, serial beta-hCG samples continue to give doubling time results while ultrasonic demonstration of a gestational sac is normally seen by 28 days after ovulation; (3) the lack of fetal heart motion by 42 days after ovulation or within a gestational sac with a mean diameter of greater than 30 mm was prognostic of abortion; (4) the absence of a gestational sac by 28 days after ovulation or with a beta-hCG RIA greater than 1,000 ng/ml is suggestive of an ectopic pregnancy until proved otherwise.