[The value of conventional magnetic resonance imaging based radiomic model in predicting the texture of pituitary macroadenoma]

Objective: To investigate the value of conventional magnetic resonance imaging (MRI) based radiomic model in predicting the texture of pituitary macroadenoma. Methods: The complete data of 101 patients with pituitary macroadenoma confirmed by surgery and pathology in Yijishan Hospital of Wannan Medical College from December 2014 to December 2019 were retrospectively analyzed. According to the texture of the intraoperative pituitary tumor, patients were divided into soft group (n=58) and hard group (n=43). They were randomly divided into training group (n=72) and validation group (n=29) at a ratio of 7∶3. All patients underwent conventional MRI scan of the pituitary gland. Itk-snap software was used to manually outline the T(1)-weighted image (T(1)WI), T(2)-weighted image (T(2)WI) and enhanced T(1)WI image section by section on tumor area of interest (ROI) and perform three-dimensional fusion. Then AK software was imported to extract texture features. The regression analysis methods of minimum redundancy maximum relevance (mRMR) and least absolute shrinkage and selection operator (LASSO) were used for feature selection and radiomic signature establishment. The reliability of the model was verified by 100 leave-group-out cross validation (LGOCV), and the predictive ability of the model was evaluated by drawing the receiver operating characteristic (ROC) curve. The decision curve analysis (DCA) was used to evaluate the clinical application value of the model. Results: The AUC (Area Under the ROC Curve) (95%CI) values of T1WI, T2WI, enhanced T1WI, and the combined sequence model to predict the texture of pituitary macroadenomas in the training and validation groups were 0.91 (0.84-0.98) and 0.90 (0.78-1.00), 0.86 (0.78-0.95) and 0.83 (0.64-1.00), 0.90 (0.83-0.97) and 0.89 (0.77-1.00),0.92 (0.85-0.98) and 0.91 (0.79-1.00), respectively. DCA demonstrated that T(1)WI, T(2)WI, enhanced T(1)WI, and combined sequence model all had good net benefits in clinical practice. Conclusions: T(1)WI, T(2)WI, enhanced T(1)WI, and combined sequence model of conventional MRI all had high efficacy in predicting the texture of pituitary macroadenoma, which provided a new quantitative method for predicting the texture of pituitary macroadenoma.

Scanning electron microscopy of antennal sensory organs of the cattle grub, Hypoderma lineatum (Diptera: Oestridae)

Hypoderma lineatum (Villers, 1789) (Diptera: Oestridae) is a hypodermosis fly that has resulted in great economic losses worldwide. The antennae of cattle grub males and females were examined through stereoscopic microscopy and scanning electron microscopy to reveal the general morphology, combined with distribution, type, size, and ultrastructure of the antennal sensilla. All of the three antennal segments (antennal scape, pedicel, and funiculus) possess microtrichiae on their surface. Mechanoreceptors only exist on the antennal scape and pedicel. The antennal funiculus presents four types of antennal sensilla: trichoid, basiconic, coeloconic, and clavate sensilla. Three distinctive characters of H. lineatum are obvious: (1) the relatively slender, flexible, and equal-height mechanoreceptors; (2) the enlarged antennal pedicel, and numerous antennal sensory pits and pit sensilla on the antennal funiculus; and (3) all types of antennal sensilla clustered in sensory pits, respectively. Additionally, the enlarged antennal pedicel and abundant sensory pits and pit sensilla might facilitate odor detection, enhance olfactory sensitivity and accuracy, and also protect the fragile antennal sensilla from mechanical irritation or damage.

Initial conditions for dark soliton generation in normal-dispersion fiber lasers

We report results of numerical simulations on the various initial conditions for dark soliton generation in an all-normal-dispersion fiber laser. All the dark solitons generated are odd dark solitons. Differently from the dark soliton generation in fibers, where an arbitrary dip could evolve into a dark soliton, it is found that the dark soliton can originate only from an initial dip with a certain parameter requirement. A bright pulse with either a hyperbolic secant square, Gaussian, or Lorentz profile can be developed into a dark soliton, provided that the parameters of the initial bright pulse are selected. Dark solitons can be generated in fiber lasers only if there is a phase jump, and this phase jump can be maintained and evolve to π during the pulse evolution.

An animal model of septicemia-induced hypercatabolic acute renal failure

A rat model of hypercatabolic acute renal failure (ARF) was developed in order to further investigate the mechanism of this condition. Sprague Dawley rats were separated into three groups: a septicemic group, an ischemic ARF group, and a hypercatabolic ARF group. Septicemia was produced by the i.p. injection of 1 x 10(7) colony-forming units/mL of Escherichia coli. Ischemic ARF was induced by 60 minutes clamping of the left renal artery following a contralateral nephrectomy. Hypercatabolic ARF was produced by combining ischemic ARF with the i.p. injection of 1 x 10(7) colony-forming units/mL of Escherichia coli. The hypercatabolic ARF group exhibited septic clinical features after the surgical procedures. The blood urea nitrogen and the serum creatinine, potassium and carbon dioxide combining power of hypercatabolic ARF were significantly higher than other two groups 24 hours after surgery. In addition, the rats wit hypercatabolic ARF had a greater loss of body weight and a higher mortality rate compared to the other two groups. The features of this form of experimental ARF are similar to the clinical characteristics of hypercatabolic ARF. Consequently, this appears to be a useful model of hypercatabolic ARF.

Study on nutritional status of maintenance hemodialysis patients

The nutritional status of 75 maintenance hemodialysis (MHD) patients was evaluated according to the dietary intake analysis, anthropometric measurements, biochemical and immunological parameters in this study. Furthermore, some possible factors which would affect nutritional status of hemodialysis patients were discussed. The results showed that hemodialysis patients demonstrated a high incidence of malnutrition. The low intake of protein and calorie, metabolic acidosis and inadequate dialysis would worsen the malnutrition while erythropoietin treatment improve the nutritional status of hemodialysis patients. Based on these results, suggestions were proposed for the improvement of nutritional status of MHD.