A flexible modulated pesticide release platform through poly(urethane-urea) microcapsules: effect of different crosslinkers compositions.

BACKGROUND: Polymeric microcapsules (MCs) have become an important issue and have attracted increasing attention because of their tunable physical and chemical properties. Diverse shell structures can confer multiple properties on MCs. RESULTS: Different polyols (1,4-butanediol and glycerin) and polyamines (triethylenetetramine and isophorondiamine) were selected as crosslinkers to obtain emamectin benzoate (EB)-loaded poly(urethane-urea) MCs (PU-MCs) by interfacial polymerization. The four obtained PU-MCs showed sphericity with different degrees of smoothness on their surfaces, and displayed a uniform size distribution ranging from 500 to 700 nm. Moreover, transmission electron microscopy showed that the shell thickness was roughly uniform, and was greatly influenced by the type and structure of the crosslinker. GI-MCs, prepared using glycerin and isophorondiamine, had the largest shell thickness. GT-MCs, obtained using glycerin and triethylenetetramine, had the highest encapsulation efficiency and drug-loading content, and BT-MCs, obtained using mixtures of 1,4-butanediol and triethylenetetramine, had the fastest release behavior. Thermogravimetric analysis revealed that the greater the degree of shell crosslinking, the higher decomposition temperature and the greater the thermal stability. A BT-MC suspension had the lowest viscosity and contact angle with the best wettability. Bioassay experiments showed that BT-MCs exhibited good insecticidal activity against Plutella xylostella larvae with a half-maximal lethal concentration of 4.19 mg/L. Furthermore, a BT-MC suspension showed good thermal and light stability, with potential applications in minimizing the toxicity of EB through sustained release. CONCLUSION: Various properties of EB-loaded PU-MCs were modulated through simple selection of different polyols and polyamines during fabrication, which might have an important role in constructing the pesticide delivery system and improving pesticide utilization. © 2024 Society of Chemical Industry.

Application of human data to predict hamstring tendon autograft diameter in Zhuang population.

BACKGROUND: To explore the value of human data from the Zhuang population via predicting the diameter of the hamstring tendon autograft in anterior cruciate ligament (ACL) reconstruction and determining the feasibility of preoperative ultrasound for prediction. METHODS: In total, 24 Zhuang patients who underwent ACL reconstruction with a 4-strand semitendinosus and gracilis tendon autograft (4 S-STG) were enrolled in this study. Before the operation, the affected semitendinosus tendon (ST) was examined by ultrasonography, and its length, diameter, cross-sectional area, and circumference were measured. The patients' basic information and body data, ie, height, weight, body mass index, lower limb length injured, and thigh circumference injured, were recorded. Their ST and gracilis tendon lengths and diameters and 4 S-STG diameter were measured during the operation. A correlation analysis was conducted between the ultrasound measurement results and human data and intraoperative tendon measurements. RESULTS: The ST diameter measured by ultrasound was correlated with the ST length and ST diameter measured during operation, and the ST circumference measured by ultrasound was correlated with the ST diameter measured during operation. The patients' body weight can be used to distinguish a 4 S-STG diameter of ≥8 mm (P < .01, mean difference = 11.59). The area under the receiver operating characteristic curve of body weight was 0.829. The final graft diameter ≥8 mm could be predicted with a body weight of 61.5 kg as the cutoff point; the sensitivity and specificity were 72.2% and 83.3%, respectively. CONCLUSION: In Zhuang patients undergoing ACL reconstruction with 4 S-STG, body weight more accurately predicted graft diameter than preoperative semitendinosus diameter.

Predicting autologous hamstring graft diameter and finding reliable measurement levels in the Zhuang population using preoperative ultrasonography.

Purpose: To evaluate the feasibility of using ultrasonography to preoperatively predict the autologous hamstring graft diameter for anterior cruciate ligament (ACL) reconstruction in the Zhuang population and determine a reliable measurement level using ultrasound. Methods: Twenty-four Zhuang patients who were scheduled for ACL reconstruction using four-strand semitendinosus tendon (ST) and gracilis tendon (G) (4S-STG) autografts were included in this study. Ultrasonographic examinations of the ST and the G on the damaged side were conducted before the operation. We recorded the transverse diameter (TD), anterior-posterior diameter (APD), cross-sectional area (CSA), and perimeter (P) of the tendons. The measurements were obtained from two levels of the tendons: the widest point of the medial femoral epicondyle (level 1) and the myotendinous junction of the sartorius (level 2). We also calculated the combined (ST + G) TD, APD, CSA, and p values. Then, we obtained the intraoperative measurements. The correlation between the ultrasonic and intraoperative measurements was analyzed, and the advantages of the ultrasonic measurements at the two different levels were compared. Results: When we measured at level 1, we found that part of the ultrasonic measurements were correlated with intraoperative measurements. The preoperative CSA of the G (P-GCSA) can be used to distinguish a 4S-STG autograft diameter of ≥8 mm (p < 0.01, mean difference = 3.7). The area under the P-GCSA curve was 0.801 (p < 0.05). A P-GCSA of 8.5 mm2 could be used to predict a 4S-STG autograft diameter of ≥8 mm with a sensitivity of 61.1% and specificity of 83.3%. However, there was no correlation between the ultrasonic and intraoperative measurements at level 2. Conclusion: Preoperative ultrasound can be used to predict the sufficient diameter of 4S-STG autografts when considering patients from Zhuang who are undergoing ACL reconstruction. The ultrasonic measurement should be obtained at the widest point of the medial femoral epicondyle.

Glutathione-Responsive Pyraclostrobin-Loaded Polyurea Microcapsules for Their Intelligent Controlled Release.

The utilization of intelligent controlled release technology to create stimuli-responsive pesticide formulations has been shown to effectively improve pesticide efficacy and reduce environmental pollution. Herein, a glutathione-responsive release polyurea (PU) microcapsules (MCs) loaded with pyraclostrobin were developed via the interface polymerization method. The pyraclostrobin-loaded PU-MCs showed a regular spherical shape with an average diameter of 480 nm. It also showed good thermal stability and rheological properties. Furthermore, the pyraclostrobin-loaded PU-MCs exhibited favorable wettability on wheat leaves, which was beneficial for enhancing the retention capacity of pesticide droplets and improving pesticide utilization. The pyraclostrobin can be released from MCs and directly proportional to glutathione (GSH) concentrations with Fickian diffusion. Importantly, the control efficacy of pyraclostrobin-loaded PU-MCs against Fusarium graminearum was positively correlated with GSH, indicating a promising candidate for a controlled release of pesticides in agriculture and laying the foundation for further field experiments.

The relationship of symptomatic thoracolumbar disc herniation and Scheuermann's disease.

PURPOSE: Symptomatic disc herniations in the thoracolumbar spine between T10/11 and L1/2 can be collectively called thoracolumbar disc herniation (TLDH). The etiology of this disorder is unclear. However, it is interesting that we have noted numerous TLDH patients have radiographic features of another spinal disorder which is Scheuermann's disease (SD). The purpose of this study is to investigate the relationship between symptomatic TLDH and SD in a symptomatic TLDH cohort. METHODS: A cohort of 63 patients with symptomatic TLDH, who had surgery was investigated. Incidences of associated SD and four radiographic signs of SD that were Schmorl's node, irregular vertebral end plate, posterior bony avulsion of the vertebra and wedge-shaped vertebra, average thoracolumbar kyphotic angle and incidences of disc herniation at segments with and without radiographic signs of SD were examined. Data from the TLDH group were compared with 57 patients undergoing surgery for lower lumbar disc herniation (LDH, L3/4-L5/S1) in the same period. RESULTS: The incidences of the four radiographic signs of SD and the incidence of associated SD were all significantly higher in the TLDH group than in the LDH group. 95.2 % of the patients in the TLDH group were diagnosed with SD (either classical SD or its atypical form). The average thoracolumbar kyphotic angle of the TLDH group was 16.9°, while that of the LDH group was 7.6° (P = 0.000). In the TLDH group, the incidences of disc herniation at segments with radiographic signs of SD were all significantly higher than at segments where no sign of SD was found. CONCLUSIONS: The high proportion of associated SD and the tendency of SD's signs to promote disc herniation in symptomatic TLDH patients suggest a close relationship between these two disorders. Symptomatic TLDH should be seen as a truly different surgical entity, that is, a special form of SD rather than just an indicator of a failing back.

Circumspinal decompression through a single posterior incision to treat thoracolumbar disc herniation.

BACKGROUND: Various surgical approaches have been successfully used in the treatment of thoracolumbar disc herniation (TLDH). Although the anterior transthoracic approach has a reputation for better visualization than the posterolateral and lateral approaches, it involves the manipulation of the thoracic and pulmonary structures. Thus, this approach is technically demanding and prone to compromising the respiratory system. An ideal approach would involve adequate visualization and be accomplished through the posterior midline approach that is familiar to spine surgeons. The objective of this retrospective preliminary clinical study was to introduce a new surgical procedure, circumspinal decompression through a single posterior incision, for the treatment of TLDH (T10/11-L1/2) and to evaluate the surgical outcome of this procedure by comparing it to the conventional anterior transthoracic approach. METHODS: In this study, 15 patients (10 males, 5 females; mean age 51 years) with symptomatic TLDH underwent the circumspinal decompression through a single posterior incision procedure between January 2008 and December 2009. Altogether, 17 herniated discs were excised, with 2 discs at T10/11, 4 discs at T11/12, 5 discs at T12/L1 and 6 discs at L1/2. Of these patients, 13 were followed up with a mean follow-up period of 23.5 months. Clinical outcomes, including operative time, blood loss, perioperative complications, postoperative time of hospitalization, neurologic status improvement, back pain and correction of local kyphosis, were investigated by comparing these data with the results from patients who underwent the anterior transthoracic approach for TLDH during the same period. The patients' neurologic status was evaluated by a modified Japanese Orthopedic Association (JOA) scoring system of 11 points. Neurologic status improvement after the surgery was assessed by calculating the recovery rate, which was equal to the (postoperative JOA score-preoperative JOA score)/(11-preoperative JOA score)×100%. The rates of patients who improved at the final follow-up were also assessed. RESULTS: The mean operative time was 183 minutes, the mean blood loss was 1067 ml, and the mean postoperative hospitalization time was 8.4 days. Three patients suffered perioperative complications, but none of these complications involved the respiratory system. Local kyphotic angles at the fusion levels were reduced. Of the 13 patients that were followed up, 12 improved at the final follow-up, with a mean recovery rate of 52.8%. Patients who underwent the circumspinal decompression procedure showed a higher percentage of improvement at the final follow-up, a higher degree of local kyphosis correction and a lower percentage of complications (especially respiratory complications) compared to patients who underwent the anterior transthoracic decompression procedure. CONCLUSIONS: The circumspinal decompression through a single posterior incision procedure is an effective and safe technique that is comparable to anterior tranthoracic approach for the surgical treatment of TLDH patients. It could be an attractive choice in certain circumstances.