High Tibial Osteotomy With Miniaci Planning Using Manual and Semiautomated Digital Measures

Background: Inadequate deformity analysis and planning before high tibial osteotomy (HTO) may result in correction errors with unsatisfactory clinical results. Indications: The purpose of this article is to describe the deformity analysis and preoperative planning before HTO. This surgery is effective for young patients with compartmental mild knee osteoarthritis. A partial deformity analysis without considering the femoral or intra-articular deformity may lead to overcorrection or excessive joint line obliquity. Preoperative planning using the Miniaci method with manual or semiautomated digital measures may help to prevent these types of errors. Technique Description: Landmarks are used at the proximal femoral side, distal condyles, proximal tibial plateau, and talus borders to define angles automatically on PeekMed software. Fujisawa point is determined to be 50% of the length of the proximal tibia, and Miniaci method is performed after defining the weightbearing line. The method can be performed manually or semiautomatically with the software. In this last case, the optimal procedure to be done to correct the malalignment is proposed by the software which automatically does the opening of the osteotomy to match the desired weightbearing axis and displays the size of the wedge in millimeters. Results: The intraobserver and interobserver reproducibility were performed by 2 different analyses and 2 different observers. The precision of the measures was confirmed based on computed tomographic (CT) scan 3-dimensional measures defined as the gold standard. All the intraobserver and interobserver reproducibility correlation coefficients and precision were satisfactory compared with the gold standard. Hip-knee-ankle angle may vary because of weightbearing situations between CT and long-axis x-rays. Discussion/Conclusion: The interest of semiautomated software for angular value measurements is now well recognized, and the inclusion of anatomical landmarks allows accurate and reproducible angular value measurements. Automatic knee osteotomy planning analyzes the metaphyseal deformity of both the tibia and the femur, and the software suggests the optimal procedure with the degree of openness to obtain the desired mechanical axis without creating excessive joint line obliquity

Development of the optimal procedure for increasing HbA1c concentration in control materials for external quality assessment

Background: The research aimed to increase certain HbA1c concentrations at medical decision levels for external quality control samples from healthy donor blood. Methods: The in vitro study was performed from October 2019 to January 2021 at Quality Control Center for Medical Laboratory at University of Medicine and Pharmacy at Ho Chi Minh City. The study observed on the conditions including the optimal buffer solutions (BAGPM, BPS, Ringer, Saline), temperature (2ºC - 8ºC, 22ºC - 24ºC, 37ºC), and glucose concentration (100 mM, 305 mM, 500 mM) affecting the HbA1c concentration in vitro to make the external quality control samples fell in normal, prediabetes, and diabetes range. At every condition, the HbA1c concentration was measured by Tina Quant method to look for the optimal procedure to increase HbA1c concentration required of the external quality control protocol. Results: The highest HbA1c concentration (11.57±0.2%) was found in BAGPM solution with 100 mM glucose after 15 days with the baseline HbA1c 5.43±0.13%; the HbA1c level increase dramatically at 37ºC in BAGPM 500 mM glucose solution in fifteen days (40.03±1.05%). Conclusions: The appropriate conditions were identified to prepare HbA1c standards for prediabetic and diabetic levels. The standards for HbA1c concentrations were recommended to prepare by incubating RBCs from non-diabetic donor blood in BAGPM solution containing glucose at 37ºC for 24 hours. Glucose concentrations should be 100 mM and 500 mM, respectively, for prediabetic level (HbA1c ~ 6.0 ± 0.12%) and diabetic level (HbA1c ~ 9.6 ± 0.17%).

Should We Delay the Second COVID-19 Vaccine Dose?

Due to the shortage in COVID-19 vaccine supplies and the alarming sanitary situation engendered by the COVID-19 pandemic, some countries have opted to delay the second dose of the COVID-19 vaccine for some period of time, aiming at getting the first dose of the vaccine to a large number of the population, before proceeding with the second doses [7, 6]. This strategy has sparked some heated debates world-wide for its pros and cons, and no clear consensus is reached among experts [5, 3]. Without taking side in this matter, we tried to answer the following question, from a pure mathematical perspective: should we delay the second dose of the vaccine or not?. We show that the answer to this question depends tightly on the efficacy of the first and the second COVID-19 vaccine doses. In particular, if the first dose is more than 50% efficient, the optimal procedure to maximize the number of effectively vaccinated sub-population is to delay the second vaccine as much as possible (the maximum period between the two doses prescribed by the clinical recommendations). On the other hand, if the efficacy of the first dose is less than 50% and the efficacy of the second dose exceeds a certain threshold, then it would be optimal to administer the second dose as quickly as possible (while respecting the minimum period between the two does as prescribed by the clinical recommendations). We provide explicitly the expression of this threshold as a function of the efficacy of first dose.

Synthesis of Naphthoxazinones in a One-Pot Two-Step Manner by the Application of Propylphosphonic Anhydride (T3P®)

A sequential one-pot two-step protocol has been elaborated for the synthesis of naphthoxazinones from 2-naphthol, methyl carbamate, and aromatic aldehydes. First, a three-component reaction was optimized with the dehydrating additive propylphosphonic anhydride (T3P®), resulting in 1-carbamatoalkyl 2-naphthols in good to excellent yields. Following the successful multicomponent approach, intramolecular acylation was performed at high temperature, again with the contribution of T3P®, resulting in naphthoxazinone derivatives in moderate yields. These two steps were optimized together in one-pot as well, and the sequential rise in the requisite temperature eventuated the optimal procedure for the multistep cascade.