The polymorphism and thermostability of nirmatrelvir, the main antiviral component of the oral COVID-19 treatment drug, were studied. Four polymorphs of nirmatrelvir were prepared by recrystallization methods. Among them, Form 1 and nirmatrelvir methyl tert-butyl ether solvate (Form 2) had been reported in the literature, while nirmatrelvir isobutyl acetate solvate (NMTW-IBAC) and nirmatrelvir ethyl acetate solvate (NMTW-EA) are two new solvates. The crystal structures were characterized by single-crystal X-ray diffraction, powder X-ray diffraction, thermogravimetric analysis and differential scanning calorimetry. The thermostability of polymorphism and crystalline transformation were also investigated by combining Hirshfeld surface analysis and interaction energy analysis. The results showed that nirmatrelvir Form 1 belongs orthorhombic crystal system with the space group P2₁2₁2₁ and one nirmatrelvir molecule included in the asymmetric unit, which has the same crystal structure as nirmatrelvir Form 4 reported in the literature. Owing to its larger thermal expansion, the differences in crystallographic parameters obtained at different temperatures were found between Form 1 and Form 4. Three solvates of nirmatrelvir belonged to the iso-structural with monoclinic crystal system and the space group P2₁, in which the asymmetric unit contains one nirmatrelvir molecule and one solvent molecule. The thermal analysis results showed that nirmatrelvir Form 1 was a solvent-free crystal form with the best thermal stability and the strongest intermolecular hydrogen bonding. Among the three solvates, NMTW-EA has the worst thermal stability and the weakest hydrogen bonding interaction between the nirmatrelvir molecule and the solvent molecule. The energy framework of nirmatrelvir solvates showed that the closer the arrangement between solvent and nirmatrelvir molecules, the greater the total interaction energy between solvent and nirmatrelvir molecules. The phase transition studies of the three solvates showed that NMTW-IBAC and NMTW-EA were transformed into amorphous after desolvation, respectively, while Form 2 undergoes oiling during desolvation. The research provides theoretical guidance for the analysis, identification and quality control of nirmatrelvir polymorphs.

BACKGROUNDRecent studies have demonstrated that dexamethasone (DEX) interferes with immune responses by targeting key functions of dendritic cells (DCs) at the earliest stage. However, the cellular and molecular mechanisms are still incompletely understood. This study aimed to explore the possible mechanisms by investigating the roles of DEX on differentiation, maturation & function of murine DCs and the effects of DEX on DCs via Toll-like receptor 4 (TLR4)-nuclear factor (NF)-kappaB mediated signal pathway.

METHODSImmature DCs (imDCs) were cultured from murine bone marrow (BM) cells. We added DEX into culture medium at different time. The expression of CD11c, CD86 and I-A(b) (mouse MHC class II molecule) was determined by flow cytometry. We determined the expression of NF-kappaB and its inhibitory protein I-kappaBalpha by electrophoretic mobility shift assay (EMSA) and Western blotting, respectively. The productions of interleukin (IL)-12p70 and IL-10 in cell culture supernatants were determined by enzyme-linked immunosorbent assay (ELISA).

RESULTSDEX impaired differentiation of DCs from murine bone marrow progenitors, and inhibited lipopolysaccharide (LPS) induced maturation of DCs. DEX significantly inhibited NF-kappaB expression of normal DCs, the higher the DEX concentration or the longer the DEX treatment time, the more obvious the effect. However, DEX had little effect on LPS-induced NF-kappaB activation, and partially impaired LPS-induced I-kappaBalpha degradation. DEX significantly decreased LPS induced IL-12p70 production by DCs. Interestingly, our results showed a synergistic effect between DEX and LPS on the production of IL-10 by DCs.

CONCLUSIONSDEX inhibits the differentiation and maturation of murine DCs involved in TLR4-I-kappaB-NF-kappaB pathway, and also indirectly impairs Th1 development and interferes with the Th1-Th2 balance through IL-12 and/or IL-10 secretion by DCs.

Animals ; Blotting, Western ; Bone Marrow Cells ; cytology ; Cell Differentiation ; drug effects ; Cells, Cultured ; Dendritic Cells ; cytology ; metabolism ; Dexamethasone ; pharmacology ; Electrophoretic Mobility Shift Assay ; Enzyme-Linked Immunosorbent Assay ; Flow Cytometry ; Male ; Mice ; NF-kappa B ; metabolism ; Signal Transduction ; drug effects ; Toll-Like Receptor 4 ; metabolism

Background: Intralesional excision with curettage is the standard method of giant cell tumor (GCT) treatment, but the ideal filling material after curettage remains controversial. The purpose of this study was to compare the oncological and functional outcomes which underwent cementation or bone grafting after GCT curettage around the knee. Methods: We reported 136 cases with GCTs in distal femur or proximal tibia who accepted curettage from five clinical centers during the last 15 years. All patients were divided into two groups according to filling materials. Recurrence?free survival proportions were used to evaluate oncological outcomes while the Musculoskeletal Tumor Society (MSTS) 93 functional score was used to evaluate functional outcomes. Other parameters including surgical complication, general condition, and radiological classification had been analyzed. The valid statisitical data was analyzed using SPSS 13.0 software. Results: After GCT curettage, 86 patients (63.2%) accepted bone grafting while 50 patients (36.8%) accepted cementation. There was no statistical difference in age, gender, tumor location, radiological classification, fixation, follow?up time, and MSTS 93 functional score between cementation group and bone grafting group. The recurrence?free survival proportions showed that the recurrence rate in bone grafting group was higher than it in cementation group (P = 0.034). Surgical complication was lower in cementation group than that in bone grafting group but without statistically significant difference (P = 0.141). Conclusions: Parameters including patients'age, gender, tumor location, and radiological classification did not affect surgeons'treatments in cavity filling after GCT curettage. Cementation should be recommended because of easy usage, the similar postoperative knee function with bone grafting, and the better local tumor control than bone grafting.

OBJECTIVETo study and compare the effect of neutrophil elastase inhibitors (GW311616A and sivelestat) on the proliferation and apoptosis of U937 cells.

METHODSInhibitory effects of GW311616A and sivelestat on the proliferation of U937 cells were assayed by MTT assay. The morphologic changes of U937 cells were detected by transmission electron microscope, and apoptosis was observed by AnnexinV-FITC/PI staining. The changes of cell cycle and apoptosis were detected by flow cytometry. The expression of NE in U937 cells was observed by indirect immunofluorescence, the variations of content and activity of NE in U937 cells were measured through ELISA assay and colorimetric method.

RESULTSMTT showed that both NE inhibitors could inhibit the proliferation of U937 cells in a dose dependent manner. The IC50 of GW311616A and sivelestat were 150 and 214 μmol/L respectively. The inhibition effect of GW311616A was significantly higher than of sivelestat (P<0.01). Typical apoptosis morphological changes of U937 cells was observed through electron microscope. AnnexinV-FITC/PI staining showed that U937 cells could be induced to undergo apoptosis by the two inhibitors, the apoptosis ratio of 150μmol/L GW311616A group (13.60%) was significantly higher than that of 150μmol/L sivelestat group (3.69%)(P<0.01). The result of flow cytometry indicated that the apoptosis ratio of 150 μmol/L GW311616A group was 14.61%, U937 cell cycle was mainly blocked in G2/M phase; meanwhile 150 μmol/L sivelestat group as 4.25% with cell cycle in S phase. The fluorescence intensity of GW311616A group obviously decreased than of sivelestat group. And the two inhibitors could reduce the content and activity of NE in U937 cells, but the effect of GW311616A was significantly higher than of sivelestat (P<0.01).

CONCLUSIONGW311616A and sivelestat could inhibit the proliferation and cause apoptosis of U937 cells. Furthermore, GW311616A was more effective and harmful to cells than sivelestat.

Apoptosis ; drug effects ; Cell Proliferation ; drug effects ; Dose-Response Relationship, Drug ; Glycine ; analogs & derivatives ; pharmacology ; Humans ; Leukocyte Elastase ; antagonists & inhibitors ; Piperidines ; pharmacology ; Proteinase Inhibitory Proteins, Secretory ; pharmacology ; Sulfonamides ; pharmacology ; U937 Cells

AIMTo investigate the role of endothelin-1 in the pathogenesis of neurogenetic pulmonary edema.

METHODSThe levels of endothelin-1 in plasma and lung were measured in rats which suffered from diffuse brain injury on Marmarous' model. The changes of endothelin-1 in the lungs were also detected using an immunohistochemical method.

RESULTSAfter heavy diffuse brain injury in rats, the levels of endothelin-1 in plasma and lung began increasing at 1 hour, and peaked at 6 hour. Though a little declining at 24 hour, it maintained a higher level within 48 hours (P < 0.05). Pulmonary pathology showed that after brain injury there were congestion, swelling in pulmonary microvessels with broadened pulmonary interstitial tissue, and leucocyte infiltration was dominated by neutrophils and monocytes from 1 hour on, which peaked at 6 hour. More serious congestion, swelling and protein effusion in pulmonary alveoli were observed at both 24 h and 48 h. Immunohistochemically, endothelin-1 had more significant expression and higher levels of OD in the experimental groups than that in the control's, the most significance of which was at 6 hour.

CONCLUSIONThe inflammatory injury mechanism caused by endothelin-1 may play an important role in neurogenic pulmonary edema.

Animals ; Endothelin-1 ; metabolism ; Lung ; metabolism ; Male ; Pulmonary Alveoli ; metabolism ; Pulmonary Edema ; etiology ; metabolism ; Rats ; Rats, Wistar

OBJECTIVETo ascertain extraction technology condition for extract and flavonoids from Chrysanthum morifoliwn.

METHODThe optimizing ultrasonic extraction condition on the basis of extractive yield and flavonoids were determined by orthogonal design.

RESULTThe order of factors which affected the flavonoid extraction was extraction times > ethanol concentration > ultrasonic time > solvent quantity.

CONCLUSIONThe optimum ultrasonic extractions are A2B3C3D3. Compared with traditional extraction, ultraction method is timesaving, simple to operate, stable and need not be heated.

Chrysanthemum ; chemistry ; Drugs, Chinese Herbal ; analysis ; Flavonoids ; analysis ; Flowers ; chemistry ; Plants, Medicinal ; chemistry ; Technology, Pharmaceutical ; methods

AIMTo study preventive and therapeutic effect of zinc sulfate on lung injury during superior mesenteric artery occlusion (SMAO) shock and their mechanism of action.

METHODSModel of rabbit SMAO shock was made. The effect of zinc sulfate on the malondialdehyde (MDA) in erythrocyte membrane and plasma, oxidase (XOD) in plasma, superoxide dismutase (SOD) in erythrocyte and MDA, SOD and pulmonary surfactant (PS) in lung tissues homogenate were observed.

RESULTSThe administration of zinc sulfate decreased MDA and XOD, prevented the reduction of SOD and PS, and alleviated lung injury.

CONCLUSIONIt is suggested that lung is injured during SMAO shock and zinc sulfate possesses preventive and therapeutic effect, through stabilized membrane.

Animals ; Female ; Lung ; metabolism ; Lung Injury ; drug therapy ; etiology ; metabolism ; Male ; Mesenteric Artery, Superior ; pathology ; Mesenteric Vascular Occlusion ; complications ; drug therapy ; metabolism ; Rabbits ; Shock ; complications ; drug therapy ; metabolism ; Zinc Sulfate ; therapeutic use

OBJECTIVETo compare the difference between J-hook and micro-implant anchorage in the treatment of patient with bimaxillary protrusion.

METHODSThirty patients with bimaxillary protrusion were divided into two groups (J-hook and micro-implant groups) and treated with MBT appliance. Four first premolars were extracted in all patients. Cephalometric analyses were carried out before and after treatment.

RESULTSIn J-hook group and micro-implant group,computerized cephalometric analysis revealed that before treatment U6C-PP was (12.4 +/- 0.2) mm and (12.5 +/- 0.1) mm, respectively,and after treatment U6C-PP was (12.6 +/- 0.1) mm and (12.8 +/- 0.1) mm,respectively. The difference between J-hook group and microimplant group was significant (P < 0.01). The other differences of cephalometric analyses between J-hook group and micro-implant group was not significant.

CONCLUSIONSBoth J-hook and micro-implant could provide adequate anchorage in the treatment of patients with bimaxillary protrusion.

Adolescent ; Adult ; Child ; Female ; Humans ; Male ; Malocclusion, Angle Class I ; therapy ; Orthodontic Anchorage Procedures ; instrumentation ; Orthodontic Appliances ; Orthodontics, Corrective ; instrumentation ; methods ; Young Adult

OBJECTIVETo summary the application of the extended free lateral arm flaps for buccal soft tissue reconstruction after buccal cancer.

METHODSFrom January to August 2011, three patients underwent the operation of buccal defect reconstruction using the extended free lateral arm flap in one-stage. PRCA was identification with the Doppler probe. According to the mark of PRCA, size and shape of defects, the flaps were designed and extended to the lateral epicondyle of humerus. The flap size ranged from 9 cm x 5 cm to 10 cm x 6 cm with a pedicle of 10 cm in length. The wounds at donor sites were closed directly.

RESULTSVascular crisis happened in one case due to local negative pressure, which resolved after emergency management. All the flaps survived completely. The patients were followed up for 6 to 10 months with no recurrence. Both the esthetic and functional results were satisfactory. Two cases suffered from numb feeling in donor sites which alleviated six months later.

CONCLUSIONSThe extended free lateral arm flap has reliable blood supply with appropriate thickness. It is an optional method for reconstruction of buccal defects after ablation of buccal cancer.

Aged ; Arm ; surgery ; Cheek ; surgery ; Facial Neoplasms ; pathology ; surgery ; Humans ; Male ; Middle Aged ; Reconstructive Surgical Procedures ; methods ; Skin Transplantation ; methods ; Surgical Flaps

OBJECTIVETo explore a new method in estimating extent and degree of arterial injury in upper limbs sustaining high tension electric burns.

METHODSEighteen patients (twenty-four upper limbs) with high tension electricity injury were admitted from December 1998 to September 2002, The damaged limbs consisted of four parts: wrist wound part, 5 cm, 10 cm, 15 cm parts around wrist wound, where the radial and ulnar arteries were detected using B ultrasound and color WP Doppler examination. The changes of endangium, vessel diameter, thickness of the vessel wall and volume of blood flow were recorded respectively. The parameters of normal radial and ulnar arteries were also determined as normal control.

RESULTSB ultrasound and color WP Doppler examination showed that the endangium in radial and ulnar arteries become coarse, edema or exfoliation. The vessel wall was thicker than that of the normal control and the thickness was heterogeneity. The vessel wall could be necrosis in severe patient and the vessel cavity was stricture or beaded. Thrombosis or occlusion could occur at the site of severe injury area in vessel. The decrease in volume of blood flow was observed. The condition of the radial and ulnar arteries become well apart from 10 - 15 cm of wrist wound.

CONCLUSIONSThe ultrasonography can be used to detect the changes in endangium, diameter, thickness of the vessel wall, blood flow volume in injury blood vessel caused by electric burn injury. It is helpful in judging the degree and extent of injury vessel and could be a safe, non-invasive diagnostic method and is worth popularizing.

Adolescent ; Adult ; Burns, Electric ; diagnostic imaging ; Female ; Humans ; Male ; Middle Aged ; Radial Artery ; diagnostic imaging ; injuries ; Ulnar Artery ; diagnostic imaging ; injuries ; Ultrasonography ; Wrist Injuries ; diagnostic imaging