We previously identified the major pathological changes in the respiratory and immune systems of patients who died of severe acute respiratory syndrome (SARS) but gained little information on the organ distribution of SARS-associated coronavirus (SARS-CoV). In the present study, we used a murine monoclonal antibody specific for SARS-CoV nucleoprotein, and probes specific for a SARS-CoV RNA polymerase gene fragment, for immunohistochemistry and in situ hybridization, respectively, to detect SARS-CoV systematically in tissues from patients who died of SARS. SARS-CoV was found in lung, trachea/bronchus, stomach, small intestine, distal convoluted renal tubule, sweat gland, parathyroid, pituitary, pancreas, adrenal gland, liver and cerebrum, but was not detected in oesophagus, spleen, lymph node, bone marrow, heart, aorta, cerebellum, thyroid, testis, ovary, uterus or muscle. These results suggest that, in addition to the respiratory system, the gastrointestinal tract and other organs with detectable SARS-CoV may also be targets of SARS-CoV infection. The pathological changes in these organs may be caused directly by the cytopathic effect mediated by local replication of the SARS-CoV; or indirectly as a result of systemic responses to respiratory failure or the harmful immune response induced by viral infection. In addition to viral spread through a respiratory route, SARS-CoV in the intestinal tract, kidney and sweat glands may be excreted via faeces, urine and sweat, thereby leading to virus transmission. This study provides important information for understanding the pathogenesis of SARS-CoV infection and sheds light on possible virus transmission pathways. This data will be useful for designing new strategies for prevention and treatment of SARS.

In order to investigate the clinical pathology of severe acute respiratory syndrome (SARS), the autopsies of three patients who died from SARS in Nan Fang Hospital Guangdong, China were studied retrospectively. Routine haematoxylin and eosin (H&E) staining was used to study all of the tissues from the three cases. The lung tissue specimens were studied further with Macchiavello staining, viral inclusion body staining, reticulin staining, PAS staining, immunohistochemistry, ultrathin sectioning and staining, light microscopy, and transmission electron microscopy. The first symptom was hyperpyrexia in all three cases, followed by progressive dyspnoea and lung field shadowing. The pulmonary lesions included bilateral extensive consolidation, localized haemorrhage and necrosis, desquamative pulmonary alveolitis and bronchitis, proliferation and desquamation of alveolar epithelial cells, exudation of protein and monocytes, lymphocytes and plasma cells in alveoli, hyaline membrane formation, and viral inclusion bodies in alveolar epithelial cells. There was also massive necrosis of splenic lymphoid tissue and localized necrosis in lymph nodes. Systemic vasculitis included oedema, localized fibrinoid necrosis, and infiltration of monocytes, lymphocytes, and plasma cells into vessel walls in the heart, lung, liver, kidney, adrenal gland, and the stroma of striated muscles. Thrombosis was present in small veins. Systemic toxic changes included degeneration and necrosis of the parenchyma cells in the lung, liver, kidney, heart, and adrenal gland. Electron microscopy demonstrated clusters of viral particles, consistent with coronavirus, in lung tissue. SARS is a systemic disease that injures many organs. The lungs, immune organs, and systemic small vessels are the main targets of virus attack, so that extensive consolidation of the lung, diffuse alveolar damage with hyaline membrane formation, respiratory distress, and decreased immune function are the main causes of death.

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Currently, supra-wavelength periodic surface structures (SWPSS) are only achievable on silica dielectrics and silicon by femtosecond (fs) laser ablation, while triangular and rhombic laser induced periodic surface structures (LIPSS) are achievable by circularly polarized or linear cross-polarized femtosecond laser. This is the first work to demonstrate the possibility of generating SWPSS on Sn and triangular and rhombic LIPSS on W, Mo, Ta, and Nb using a single linearly polarized femtosecond laser. We discovered, for the first time, SWPSS patches with each possessing its own orientation, which are completely independent of the light polarization direction, thus, breaking the traditional rules. Increasing the laser power enlarges SWPSS periods from 4–6 μm to 15–25 μm. We report a maximal period of 25 μm, which is the largest period ever reported for SWPSS, ∼10 and ∼4 times the maximal periods (2.4 μm/6.5 μm) of SWPSS ever achieved by fs and ns laser ablation, respectively. The formation of triangular and rhombic LIPSS does not depend on the laser (power) or processing (scan interval and scan methodology) parameters but strongly depends on the material composition and is unachievable on other metals, such as Sn, Al, Ti, Zn, and Zr. This paper proposes and discusses possible mechanisms for molten droplet generation/spread/solidification, Marangoni convection flow for SWPSS formation, and linear-to-circular polarization transition for triangular and rhombic LIPSS formation. Reflectance and iridescence of as-prepared SWPSS and LIPSS are characterized. It was found that besides insufficient ablation on W, the iridescence density of Ta-, Mo-, Nb-LIPSS follows the sequence of melting temperatures: Ta > Mo > Nb, which indicates that the melting temperature of metals may affect the regularity of LIPSS. This work may inspire significant interest in further enriching the diversity of LIPSS and SWPSS.

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The demand is growing for new nanoscience-based technologies with unique properties that are different from traditional wet-chemical techniques. In recent years, laser ablation in liquid (LAL) has attracted increasing attention for nanomaterial synthesis, which has rapidly advanced both fundamental research and applications. Compared to other techniques, LAL is easy to set up and simple to perform. A large diversity of bulk and powder targets can be employed for LAL, which combined with an enormous variety of liquids, greatly diversify the nanomaterials that can be synthesized by LAL in terms of size, composition, shape, and structure. Although many reviews related to LAL have been published, a comprehensively thorough introduction that deals with the diversity of the targets and liquids used for LAL is still missing. To fill this gap, this review gives a comprehensive summary of the nanomaterials synthesized by LAL using different types of target and liquid, with an emphasis on the effects of liquids on the final nanoproducts. In order to provide a better understanding of the liquids’ effects, this review also discusses liquid additives such as salts, polymers, support materials, and their mixtures. Since many reactions occur during LAL, the scope of reactive laser ablation in liquid (RLAL) is redefined, and the representative reactions for each type of liquid used for LAL are summarized and highlighted. Consequently, this review will be a useful guide for researchers developing desirable nanomaterials via LAL.