Intramedullary nailing for irreducible spiral subtrochanteric fractures: A comparison of cerclage and non-cerclage wiring.

PURPOSE: Intramedullary nailing is the preferred internal fixation technique for the treatment of subtrochanteric fractures because of its biomechanical advantages. However, no definitive conclusion has been reached regarding whether combined cable cerclage is required during intramedullary nailing treatment. This study was performed to compare the clinical effects of intramedullary nailing with cerclage and non-cerclage wiring in the treatment of irreducible spiral subtrochanteric fractures. METHODS: Patients with subtrochanteric fractures admitted to our center from January 2013 to December 2021 were retrospectively analyzed. The patients were enrolled in the case-control study according to the inclusion and exclusion criteria and divided into the non-cerclage group and the cerclage group. The patients' clinical data, including the operative time, intraoperative blood loss, hospital stay, reoperation rate, fracture union time, and Harris hip score, were compared between these 2 groups. Categorical variables were compared using Chi-square or Fisher's exact test. Continuous variables with normal distribution were presented as mean ± standard deviation and analyzed with Student's t-test. Non-normally distributed variables were expressed as median (Q1, Q3) and assessed using the Mann-Whitney test. A p value < 0.05 was considered significant. RESULTS: In total, 69 patients were included in the study (35 patients in the non-cerclage group and 34 patients in the cerclage group). The baseline data of the 2 groups were comparable. There were no significant difference in the length of hospital stay (z = -0.391, p = 0.696), operative time (z = -1.289, p = 0.197), or intraoperative blood loss (z = -1.321, p = 0.186). However, compared with non-cerclage group, the fracture union time was shorter (z = -5.587, p < 0.001), the rate of nonunion was lower (χ2 = 6.030, p = 0.03), the anatomical reduction rate was higher (χ2 = 5.449, p = 0.03), and the Harris hip score was higher (z = -2.99, p = 0.003) in the cerclage group, all with statistically significant differences. CONCLUSIONS: Intramedullary nailing combined with cable cerclage wiring is a safe and reliable technique for the treatment of irreducible subtrochanteric fractures. This technique can improve the reduction effect, increase the stability of fracture fixation, shorten the fracture union time, reduce the occurrence of nonunion, and contribute to the recovery of hip joint function.

New Friedel-Crafts strategy for preparing 3-acylindoles.

A selective Friedel-Crafts acylation of indoles via an unusual cleavage of the amide C-N bond was achieved by triflic anhydride activation. This method offers rapid efficient access to high-biological-value 3-acylindoles, performs a series of scrupulous mechanistic studies and offers a strong courage that amide synthons can form new C-C bonds under transition-metal-free conditions.

Synthesis of Functionalized Quinolines through a Reaction of Amides and Alkynes Promoted by Triflic Anhydride/Pyridine.

A concise, novel and flexible metal-free single step to synthesize functionalized quinolines is reported. Triflic anhydride-mediated (Tf2 O) activation of amides is discussed in the presence of pyridine to offer strong electrophiles, thereby showcasing excellent productivity, high regio- and chemoselectivity, and widely tolerable substrates. This approach provides a straightforward and efficient way to construct azaheterocycle structures.

Iodine-Promoted Radical Cyclization in Water: A Selective Reaction of 1,6-Enynes with Sulfonyl Hydrazides.

An iodine-promoted one-pot radical cyclization reaction of 1,6-enynes with sulfonyl hydrazides to provide five-membered and hexatomic ring sulfonylated products under the same conditions is established. This reaction proceeded smoothly in water and gave the corresponding products by using I2/TBHP instead of expensive and toxic catalysts with C-S and C-I bond formed in one step. This method also allowed easy access to significant functional sulfones for potential applications in medicinal and organic chemistry.

Zinc-catalyzed [4+3] cycloaddition with concomitant furan annulation: formation of cyclohepta[b]furans.

A convenient zinc-promoted [4+3] cycloaddition of a carbonyl ene-yne with simple dienes was first achieved. This reaction provided an efficient strategy to prepare various cyclohepta[b]furan rings by cascade cycloadditions. Additionally, a multicomponent reaction of dione, alkynal, and diene was also reported, which exhibited a novel strategy for selective creations of C-O bonds and C-C bonds.

Factors affecting the performance of a single-chamber microbial fuel cell-type biological oxygen demand sensor.

Microbial fuel cells (MFCs) are devices that exploit microorganisms as biocatalysts to degrade organic matter or sludge present in wastewater (WW), and thereby generate electricity. We developed a simple, low-cost single-chamber microbial fuel cell (SCMFC)-type biochemical oxygen demand (BOD) sensor using carbon felt (anode) and activated sludge, and demonstrated its feasibility in the construction of a real-time BOD measurement system. Further, the effects of anodic pH and organic concentration on SCMFC performance were examined, and the correlation between BOD concentration and its response time was analyzed. Our results demonstrated that the SCMFC exhibited a stable voltage after 132 min following the addition of synthetic WW (BOD concentration: 200 mg/L). Notably, the response signal increased with an increase in BOD concentration (range: 5-200 mg/L) and was found to be directly proportional to the substrate concentration. However, at higher BOD concentrations (>120 mg/L) the response signal remained unaltered. Furthermore, we optimized the SCMFC using synthetic WW, and tested it with real WW. Upon feeding real WW, the BOD values exhibited a standard deviation from 2.08 to 8.3% when compared to the standard BOD5 method, thus demonstrating the practical applicability of the developed system to real treatment effluents.

Formation of o-Allyl- and Allenyl-Modified Amides via Intermolecular Claisen Rearrangement.

We developed a new transition-metal-free intermolecular Claisen rearrangement process to introduce allyl and allenyl groups into the α position of tertiary amides. In this transformation, amides were activated by trifluoromethanesulfonic anhydride to produce the keteniminium ion intermediates that exhibit strong electrophilic activity. This atom-economical process delivers α position-modified amides under mild conditions in moderate to good yields and showcases a broad substrate compatibility.

[Therapeutic efficacy of augmentative plate fixation in long-bone hypertrophic nonunion subsequent to intramedullary nailing].

OBJECTIVE: To determine the therapeutic efficacy of augmentation plate fixation in nonunion of long-bone fracture after interlocking intramedullary nailing. METHODS: From April 1998 to April 2009, 14 patients with long-bone hypertrophic nonunion after intramedullary nail internal fixation were treated with augmentative plate. There were nine patients with nonunion of femur, three of humerus and two of tibia. After implanting the intramedullary nail in situ, an augmentative plate fixation was applied to the fracture site to counter the rotational instability. A general plate with at least two screws reaching the opposite cortical bone above and below the fracture was fixated to the lateral side of bone shaft. In all patients, the rotational instability of fracture site was verified intra-operatively in all cases. However, motion disappeared after plate augmentation. RESULTS: All patients achieved radiological solid union at an average of 8 months (range: 6 - 11). Hardware was removed in six cases at 6-11 months post-operation. No infection, hardware loosening or rupture was found. CONCLUSION: The augmentative plate fixation can be applied at the fracture site to prevent the rotational instability. Augmentation plate fixation is indicated for femoral and tibial nonunion of proximal or distal metaphyseal-diaphyseal junctional areas, primary comminuted fracture and humeral nonunion after intramedullary nailing.

Organocatalyzed Synthesis of Functionalized Quinolines.

As one of the most widely investigated compound skeleton, quinolines possess important medicinal and biological activities. As such, a great number of literatures, including reviews, have reported various methodologies to construct quinolines. Recently, organocatalyzed reactions have attracted the attention of organic chemists due to its being "green" because the reactions avoid the use of toxic metals. In this review, various distinctive contributions are surveyed with specific emphasis on organocatalyzed reactions for quinoline core constructions.

[Curative effect of anterolateral spinal canal decompression combined with short segment screw fixation with posterior approach for severe thoracolumbar burst fractures with spinal cord injury].

OBJECTIVE: To explore the effect of anterolateral spinal canal decompression combined with short segment screw fixation with posterior approach for severe thoracolumbar burst fractures with spinal cord injury. METHODS: From January 2016 to June 2018, 16 patients with severe thoracolumbar burst fractures (more than 50% of ratio of spinal canal encroachment, reverse fragment at the posterior edge of the vertebral body) with spinal cord injury were retrospectively analyzed, including 10 males and 6 females, ranging in age from 19 to 57 years old. Causes of injury:8 cases of fall injury, 6 cases of traffic accident injury and 2 cases of other injuries. Fracture site:T11 in 4 cases, T12 in 5 cases, L1 in 5 cases, L2 in 2 cases. All the patients underwent anterolateral spinal canal decompression combined with short segment screw fixation with posterior approach. The curative imaging effects were evaluated by measuring the loss height of the anterior edge of the injured vertebra, Cobb angle of the adjacent segment of the injured vertebra, and ratio of spinal canal encroachment. The clinical effects were evaluated by Frankel spinal cord injury rating and visual analogue scale (VAS). RESULTS: All 16 patients were followed up, and the average follow up time was (15.9±5.4) months. The average operation time was (234±41) minutes and the average amount of bleeding was (431±93) ml. The loss of anterior height of injured vertebrae was (52.25±10.10)% before operation, (8.93± 3.61)% at 3 days after operation, and (9.25±2.88)% at the latest follow up. The results of 3 days after operation and the latest follow up were better than that before operation, and there was no significant differencesbetween results at the latest follow up and 3 days after operation (P<0.01). Cobb angle of adjacent segment of injured vertebrae was (28.19±10.89)°before operation, (5.31±5.14)° 3 days after operation, and (6.81±4.59)°at the latest follow-up. The ratio of spinal canal encroachment was (67.68±12.45)% before operation, (7.69±4.46)% at 3 days after operation, and (4.75±1.63)% at the latest follow-up. At 3 days and the latest follow-up, the rate recovered to a certain extent (P<0.05). At the latest follow up, spinal nerve function was improved in 12 patients, no improvement in 4 patients and no deterioration in nerve function. VSA score was improved from preoperative 7.8±0.9 to final follow-up 1.8±0.7. CONCLUSION: For severe thoracolumbar burst fracture and spinal cord injury, with more than 50% of ratio of spinal canal encroachment and reverse fragment at the posterior edge of the vertebral body, the anterolateral spinal canal decompression combined with short segment screw fixation with posterior approach has the characteristics of accurate reduction, complete decompression and firm fixation, and the clinical effect is satisfactory.

Transition-metal-free multinitrogenation of amides by C-C bond cleavage: a new approach to tetrazoles.

A metal-free brand-new one-pot multinitrogenation of amides for the chemo- and regioselective synthesis of 1,5-disubstituted tetrazoles has been developed. By means of electrophilic amide activation, and further C-C bond cleavage and rearrangement, a diverse set of functionalized 1,5-DST derivatives were selectively constructed under mild conditions. As showcased in the mechanisms, the chemoselectivity is easily switched by the selection of the starting materials in the reaction.

[Effect of the Food to Mass Ratio and Hydraulic Retention Time on Hydrogen Production from Fruit and Vegetable Waste].

Semi-continuous biogas production from fruit and vegetable waste by medium temperature anaerobic fermentation was conducted. Hydrogen production under different food-microorganism ratios (F/M 0.5, 0.75, 1.0, 1.5) and hydraulic retention times (HRT) (2, 3, 4 d) were investigated. The results show that in the case of a smaller F/M values (0.5 and 0.75), not all HRT stages were conducive to the continuous production of hydrogen, however, they were conducive to producing methane, especially when HRT was 3 or 4 d. Continuous hydrogen production was viable when the F/M ration was relatively higher (1.0 and 1.5), however, this was not conducive to the production of methane, with almost no methane production detected in this process. A F/M of 1.0 and a HRT of 3 d provided the best conditions for continuous hydrogen production from fruit and vegetable waste. Meanwhile, the highest and average daily volume of hydrogen production were 451.2 mL·(L·d)-1 and (186±29) mL·(L·d)-1 respectively, whereas the highest and average hydrogen production rate of volatile solids were 133 mL·g-1 and (27±5) mL·g-1 respectively. The hydrogen content was 20%-30%.

[In vitro gene transfection into rabbit articular chondrocytes mediated by recombinant adeno-associated virus vector].

OBJECTIVE: To investigate the in vitro efficiency of recombinant adeno-associated virus (rAAV2) vector-mediated gene transfection into the rabbit articular chondrocytes. METHODS: Articular chondrocytes were isolated from New Zealand rabbits, cultured, and transfected with rAAV2 containing enhanced green fluorescent protein (eGFP) gene at different values multiplicity of infection (MOI). Successful transfection of chondrocytes was confirmed by detection of recombinant enhanced green fluorescent protein using inverted fluorescence microscopy. The transfection efficiency was determined using the fluorescence-activated cell sorter. A maximum level of 4.76% was set as the background autofluorescence in live, uninfected chondrocytes. RESULTS: The percentage of eGFP-positive chondrocytes increased in a vector dose-dependent manner. When the MOI value was <1 x 10(5) v.g./cell the transfection rate was positively linearly correlated with the dose. However, the MOI > 10(5) v.g./cell did not markedly increase the transfection rate. The greatest population of eGFP-expressing cells was 97.7% and the highest mean fluorescence intensity was 17.4 7 days after transfection. EGFP gene expression remained high until 56 days after transfection. CONCLUSION: The in vitro efficiency of rAAV2 vector-mediated eGFP gene transfection into rabbit articular chondrocytes was high. The eGFP expression can be maintained for a rather long time. EGFP gene is an ideal tracer for chondrocytes transduction.

Synthesis of ß-Difluoroalkylated Acrylonitriles in the Presence of Copper Powder.

A highly regio- and stereoselective copper-mediated cyanodifluoroalkylation of alkynes with ethyl difluoroiodoacetate and trimethylsilyl cyanide (TMSCN) is described. The three-component coupling reaction provides straightforward access to a variety of useful difluoroalkyl-substituted acrylonitriles. The introduction of the nitrile unit is of great importance in drug discovery for the modification of this fragment. Preliminary mechanistic investigations indicate that a vinyl iodide intermediate and a difluoroalkyl radical might be involved in this transformation.

Lewis Acid Catalyzed [4 + 3] Cycloaddition of Propargylic Alcohols with Azides.

An unprecedented Lewis acid catalyzed [4 + 3] cycloaddition reaction is described that provides a straightforward route to polycyclic products containing an imine-based indole azepine scaffold, starting from readily available internal tertiary alkynols and azides. This cycloaddition protocol provides efficient and atom-economical access to a new class of fascinating imine-containing products in satisfactory yields, which has shown good application in the construction of seven-membered N-heterocycles.

Less wound complications of a sinus tarsi approach compared to an extended lateral approach for the treatment of displaced intraarticular calcaneal fracture: A randomized clinical trial in 64 patients.

BACKGROUND: We conducted a prospective randomized clinical trial to compare the clinical and radiological outcomes of the sinus tarsi and extended lateral approaches for the surgical treatment of displaced intraarticular calcaneal fractures. METHODS: Between January 2009 and January 2014, patients with displaced intraarticular calcaneal fracture were randomly assigned to receive surgical treatment by the sinus tarsi approach or the extended lateral approach using block randomization. We recorded and analyzed data on demographics, time to surgery, wound complications, Böhler angles pre- and postoperatively, and American Orthopedic Foot & Ankle Society score. RESULTS: Sixty-four patients met the inclusion criteria and were randomly assigned to the 2 groups: 32 patients underwent sinus tarsi approach, and 32 patients the extended lateral approach. Baseline characteristics of both groups were similar. The time to surgery in the sinus tarsi approach group was significantly shorter than in the extended lateral approach group (P = 0.04). The wound complication rates were 6.3% and 31.2% in the sinus tarsi approach and extended lateral approach groups, respectively, which was significantly different (P = 0.01). Regarding the clinical outcomes, the groups did not differ significantly on walking visual analogue scale or American Orthopedic Foot & Ankle Society scores at 6 months and 1 year postoperatively. No significant differences existed between groups regarding the Böhler angle at different times and reduction quality of the articular surface and the medial wall. CONCLUSION: Compared with the extended lateral approach, the sinus tarsi approach decreased wound complications and preoperative waiting time, and achieved similar functional and radiological outcomes for displaced intraarticular calcaneal fractures.

[Clinical and pathologic features of malignant myoepithelioma of salivary glands].

OBJECTIVE: To analyze the clinical features, morphology and biologic behavior of primary malignant myoepithelioma (MME) of salivary glands. METHODS: The H&E sections of 16 MME cases were reviewed. Immunohistochemical study using EnVision method for cytokeratin (CK), epithelial membrane antigen (EMA), vimentin, S-100 protein, desmin, muscle-specific actin (MSA), smooth muscle actin (SMA), Myo, proliferation cell nuclear antigen (PCNA), leukocyte common antigen (LCA) and glial fibrillary acidic protein (GFAP) was carried out. RESULTS: Of the 16 patients studied, 6 were males and 10 were females. Their ages ranged from 12 to 65 years (with an average age of 44 years). The tumor occurred predominantly in the parotid gland and minor salivary gland of the palate. Common clinical features included sudden and rapid tumor growth, superficial ulceration, bony destruction and nerve infiltration. Seven of the 16 patients developed local recurrences, while 2 patients had metastasis in the lymph nodes of submandibular or other cervical regions. Most tumors infiltrated adjacent normal salivary gland, adipose, muscular and bony tissues. The extent of local invasion however varied. Histologically, MME showed a wide range of morphologic appearance, with various combinations of clear, spindle, epithelioid or plasmacytoid cells. The tumor cells were atypical and demonstrated high mitotic activity. In this study, 9 cases were composed predominantly of clear tumor cells. Immunohistochemically the tumor cells were positive for CK, EMA, MSA, desmin and S-100 protein. CONCLUSIONS: In general, MME is a rare and low-grade malignant salivary gland tumor. It carries a low potential for lymph node or distant metastasis but relatively high tendency for local recurrences, resulting in destruction of adjacent soft and bony tissues. The biologic behavior also varies, depending on the site of involvement. Morphologic diagnosis of MME can be difficult in view of the wide spectrum of histologic changes. A definitive diagnosis however is possible with the application of immunohistochemistry.

[Reconstruction intramedullary nailing for treatment of ispsilateral femoral neck and shaft fractures].

OBJECTIVE: To evaluate the curative effect and surigical skills of reconstruction intramedullary nailing in the treatment of ipsilateral femoral neck and shaft fractures. METHODS: From January 2007 to January 2013, 13 patients with ipsilateral femoral neck and shaft fractures were treated by reconstruction intramedullary nailing including 11 males and 2 females with an average age of 38.9 yeas old ranging from 25 to 53 years old. For femoral neck fractures,10 cases were basilar neck fracture, 3 were transcervical fractures and according to Garden classification,10 were type II, 2 were type III and 1 was type IV. For feormal shaft fracture, 5 were type I, 4 were type II, 3 were type III and 1 was type IV according to Winquist classification. The location of all 13 feormal shaft fractures were all in the uper 3/4 of the feormal shaft. Complications and postoperative function were recorded and evaluated. RESULTS: Eleven patients were followed up for 23.45 months (12 to 36 months). Time from injury to operation was 5.9 days in average. Malunion of femoral neck fracture happened in 1 patient, nonunion of femoral shaft fracture happened in 2 patients. NO femoral head osteonecrosis, infection and malunion of femoral shaft fracture happened. According to Friedman-Wyman classification, 8 cases get good result, 2 get faii and 1 get poor. CONCLUSION: Reconstruction intramedullary nailing is a good choice for the ipsilateral femoral neck and shaft fractures with the advantages of less soft-tissue trauma and complications.

Palladium-Catalyzed Intermolecular Aryldifluoroalkylation of Alkynes.

A palladium-catalyzed aryldifluoroalkylation of alkynes with ethyl difluoroiodoacetate and arylboronic acids as reaction partners is described. The alkyne difunctionalization process provides various aryldifluoroalkylated products in one pot under mild reaction conditions. A wide range of alkynes and diverse arylboronic acids are compatible with these reaction conditions. High reaction efficiency and broad substrate scope are the notable features of this transformation. Preliminary mechanistic investigations indicate that a difluoroalkyl radical addition pathway is involved in this transformation.

[Effect of Sorbaria Sorbifolia extract on anti-oxidative activities in rats with precancerosis induced by diethylnitrosamine].

OBJECTIVE: To study the effect of Sorbaria Sorbifolia extract on anti-oxidative activities in rats with precancerosis induced by diethylnitrosamine. METHODS: Sorbaria sorbifolia was perfused into stomach of rats with DEN-induced precancerosis, then the biochemical indexes were investigated. The activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-PX), and the concentrations of malondialdehyde (MDA), glutathione (GSH) were investigated by colorimetric method. RESULTS: Sorbaria sorbifolia extract increased SOD, GSH-PX and decreased MDA, GSH levels in serum and liver homogenate. CONCLUSION: Sorbaria Sorbifolia extract significantly increased anti-oxidative activities in rats with precancerosis induced by diethylnitrosamine.