Challenges in control of Covid-19: short doubling time and long delay to effect of interventions

The unconstrained growth rate of COVID-19 is crucial for measuring the impact of interventions, assessing worst-case scenarios, and calibrating mathematical models for policy planning. However, robust estimates are limited, with scientific focus on the time-insensitive basic reproduction number R0. Using multiple countries, data streams and methods, we consistently estimate that European COVID-19 cases doubled every three days when unconstrained, with the impact of physical distancing interventions typically seen about nine days after implementation, during which time cases grew eight-fold. The combination of fast growth and long detection delays explains the struggle in countries response better than large values of R0 alone, and warns against relaxing physical distancing measures too quickly. Testing and tracing are fundamental in shortening such delays, thus preventing cases from escalating unnoticed.

Progress on radionuclide-labeled small peptides in targeting tumor angiogenesis / 中国肿瘤临床

Early diagnosis and precision medicine generally show significant differences in the prognosis of patients with carcinoma. Angiogenesis not only plays a key role in tumor pathophysiology but also acts as an important drug target. Peptides with specific se-quences can target specific molecules on the endothelial cellular membrane during tumor angiogenesis. Radionuclide-labeled molecu-lar probes exhibit many advantages in oncotherapy. This article focuses on the progress of radionuclide-labeled RGD and RRL in radio-immunoimaging and radioimmunotherapy targeting tumor angiogenesis.

SPECT and CT in Evaluating Preoperative Renal Function of Patients with Unilateral Hydronephrosis / 中国医学影像学杂志

Purpose To analyze the relationships between glomerular filtration rate (GFR) measured by SPECT and renal parenchyma thickness and enhanced CT value measured by CT, and to explore predictive significance of CT in evaluating renal function of patients with hydronephrosis.Materials and Methods One hundred and fifteen patients diagnosed with unilateral hydronephrosis by ultrasound were retrospectively analyzed. GFR% (GFR percentage of affected kidney to the both kidneys) was measured by SPECT. CT% (percentage of affected renal parenchyma thickness to the both kidneys) and enhanced CT% (percentage of enhanced CT value of affected kidney to the both kidneys) were measured by pre- and post-contrast CT scan. According to GFR, the renal function was divided into mild-to-moderate impairment, severely impairment and non-function. Twenty-five volunteers were recruited as control group. CT%, enhanced CT% and GFR%among the four groups were compared, and the correlation of CT% and enhanced CT%with GFR% was analyzed to evaluated CT in predicting renal function.Results CT%, enhanced CT% and GFR% in mild-to-moderate impairment group was significantly greater than those in severely impairment group and non function group (F=20.24, 7.78 and 329.21,P<0.05). GFR% was positive correlated with CT% (r=0.58,P<0.05) and enhanced CT% (r=0.61,P<0.05). Area under curve (AUC) of CT% were 0.54, 0.79 and 0.83 for mild-to-moderate impairment, severely impairment and non-function, with sensitivity of 92.91%, 93.47%, 65.72%, and specificity of 35.33%, 59.47%, and 88.62%, respectively. AUC of enhanced CT% were 0.79, 0.89 and 0.96 for the three groups, with sensitivity of 97.51%, 80.02%, 97.66%, and specificity of 58.14%, 89.82% and 94.27%, respectively.Conclusion There was high correlation between renal function imaging by SPECT and CT in evaluating renal function of hydroneohrosis patients. Pre- and post-contrast CT scan can be used as complements in predicting renal function, and post-contrast CT with high accuracy.

A clinical study on the treatment of mucocele by bleomyin A5 combined with phosphorus-32 colloid / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To evaluate the effect of bleomyin A5 combined with phosphorus-32 colloid in the treatment of mucocele.</p><p><b>METHODS</b>A total of 214 patients divided into three groups, bleomyin A5 (50 cases), phosphorus-32 colloid (50 cases) and bleomyin A5 combined with phosphorus-32 colloid (114 cases).</p><p><b>RESULTS</b>The efficacy of bleomyin A5 group, phosphorus-32 colloid group, and bleomyin A5 combined with phosphorus-32 colloid group was 84% (42/50), 82% (41/50) and 98% (112/114), respectively. There were significant difference in efficacy among the three groups (P < 0.05). The phosphorus-32 colloid group and the bleomyin A5 group had no significant difference in efficacy (P > 0.05).</p><p><b>CONCLUSIONS</b>The independent use of bleomyin A5 and phosphorus-32 colloid is effective, but the combined use of the two methods is more effective.</p>