RESUMO
Plant leaf morphological and photosynthetic physiological characteristics are key functional traits in the adaptability of plants to heterogeneous environments. Analysis of the correlation between leaf morphological traits and photosynthetic physiological characteristics of salt marsh plants is helpful to deepen our understanding of how salt marsh plants adjust their leaf structure and function to adapt to their environment. However, there have been few studies on the relationship between leaf morphology and photosynthetic physiological characteristics of plants in inland salt marshes under a habitat gradient. A Phragmites australis community was divided into three plots based on differences in the wetland habitat conditions: a remote water area (plot I, 400-550 m from the water margin), a middle water area (plot II, 200-350 m from the water margin) and a near water area (plot III, 0-150 m from the water margin). The relationship between leaf morphological traits and photosynthetic physiological parameters of P. australis in heterogeneous habitats was studied. The results showed that as the habitat conditions changed from plot I to plot III, the soil characteristics, above-ground characteristics of the community and the photosynthetically active radiation changed significantly (P < 0.05). Besides, there was a highly significant positive correlation (P < 0.01) between leaf dry weight (LDW) and net photosynthetic rate (P n), the effective quantum yield of PSII photochemistry (Y(II), actual photochemical efficiency of PSII) and photochemical quenching (QP); and between leaf area and P n, Y(II) and QP in the three habitats. Moreover, in plot I, P. australis tended to have small and thick leaves with a low LDW and specific leaf area. In plot III, leaves were large and thin to adapt to the change in habitat conditions. This study provides a scientific theoretical basis for understanding the ecological adaptation strategies of plants in the harsh environment of an inland salt marsh and the conservation and management of wetland plants.
RESUMO
@#Abstract: To analyze the clinical, therapeutic and laboratory characteristics of disseminated cryptococcosis caused by Cryptococcus neoformans invading the blood stream in patient with liver cirrhosis and splenectomy. A 30-year-old male underwent splenectomy plus pericardial devascularization due to "splenomegaly and hypersplenism" in March in 2016. The patient had intermittent fever after operation for many times, and successively accompanied with back pain, left lower limb abscess and right hip pain. The highest body temperature was 39 ℃. CT and MRI revealed the lung lesion and multiple bone destruction. During that period, the effect of antibiotics was not good. On April 19th, 2017, Gram's stain, India ink stain, API 32C, Vitek 2 Compact, ribosomal ITS and IGS sequence analysis were performed to identify the strain isolated from the pus and blood stream. The serum of the patient was detected for cryptococcal antigen. Antifungal susceptibility test was used to determine drug sensitivity and minimum inhibitory concentration (MIC). The Cryptococcus neoformans isolated from fresh pus specimen showed a prominent, thick capsule after India ink stain. The colonies isolated from pus and blood stream were identified Cryptococcus neoformans using API 32C, Vitek 2 Compact, and sequence analysis of rDNA ITS and IGS. Cryptococcal capsule antigen was positive. The minimal inhibitory concentrations of 5-Flucytosine, amphotericin B, fluconazole, itriconazole, voriconazole against the isolate were <4 μg/mL, <0.5 μg/mL, 4 μg/mL, ≤0.25 μg/mL, 0.125 μg/mL respectively. The patient was initially treated with intravenous amphotericin B and flucytosine. After anti-Cryptococcus treatment for two months, the patient clinically improved, and the lesions were reduced on a follow-up CT scan. The patient made a full functional recovery after treatment for six months. Cryptococcosis has hidden onset, atypical clinical symptoms and lack of specificity. Blood stream is the main channel for Cryptococcus to spread and involve many organs of the whole body, including skin, bone and so on. Therefore, early use of blood culture to monitor blood flow dissemination, actively removing the primary focus and cutting off the infection route in time and carrying out effective anti-Cryptococcus treatment are conducive to the patient's early recovery.
