An occluded cherry tomato recognition model based on improved YOLOv7.

The typical occlusion of cherry tomatoes in the natural environment is one of the most critical factors affecting the accurate picking of cherry tomato picking robots. To recognize occluded cherry tomatoes accurately and efficiently using deep convolutional neural networks, a new occluded cherry tomato recognition model DSP-YOLOv7-CA is proposed. Firstly, images of cherry tomatoes with different degrees of occlusion are acquired, four occlusion areas and four occlusion methods are defined, and a cherry tomato dataset (TOSL) is constructed. Then, based on YOLOv7, the convolution module of the original residual edges was replaced with null residual edges, depth-separable convolutional layers were added, and jump connections were added to reuse feature information. Then, a depth-separable convolutional layer is added to the SPPF module with fewer parameters to replace the original SPPCSPC module to solve the problem of loss of small target information by different pooled residual layers. Finally, a coordinate attention mechanism (CA) layer is introduced at the critical position of the enhanced feature extraction network to strengthen the attention to the occluded cherry tomato. The experimental results show that the DSP-YOLOv7-CA model outperforms other target detection models, with an average detection accuracy (mAP) of 98.86%, and the number of model parameters is reduced from 37.62MB to 33.71MB, which is better on the actual detection of cherry tomatoes with less than 95% occlusion. Relatively average results were obtained on detecting cherry tomatoes with a shade level higher than 95%, but such cherry tomatoes were not targeted for picking. The DSP-YOLOv7-CA model can accurately recognize the occluded cherry tomatoes in the natural environment, providing an effective solution for accurately picking cherry tomato picking robots.

Nobiletin inhibits cell growth through restraining aerobic glycolysis via PKA-CREB pathway in oral squamous cell carcinoma.

BACKGROUND/AIM: Nobiletin is a polymethoxylated flavone enriched in Citrus and is used as an important drug in traditional Chinese medicine for various kinds of diseases. Among its multiple functions, it has shown that nobiletin inhibits proliferation of various cancer cells. However, it is unclear whether nobiletin inhibits the growth of oral squamous cell carcinoma (OSCC) cells. MATERIALS AND METHODS: We explored the antitumor effects of nobiletin in TCA-8113 and CAL-27 oral squamous cells. The Cell Counting Kit-8 (CCK8) assay was used to measure cell vitality. Flow cytometry was performed to measure the number of cells in the various phases of the cell cycle. PCR and Western blot were applied to determine mRNA and protein expression, respectively. RESULTS: Nobiletin inhibited proliferation of TCA-8113 and CAL-27 cells via inducing cell cycle arrest at the G1 phase. In addition, the levels of phosphorylated-PKA and phosphorylated-CREB were reduced in nobiletin-treated TCA-8113 and CAL-27 cells. Importantly, our results showed that nobiletin treatment resulted in impaired mitochondrial function and altered glucose consumption, and pyruvate and lactate production. Lastly, nobiletin was found to inhibit the generation of xenografts in vivo. Interestingly, administration of 50 µmol/L Sp-cAMP, a potent PKA activator, rescued all phenotypes caused by nobiletin. CONCLUSIONS: Nobiletin inhibits OSCC cell proliferation in a mitochondria-dependent manner, indicating that it may have a promising role in cancer treatment and attenuation of drug resistance.

High proton conductivity behavior in a 2D metal sulfite constructed from a histidine ligand.

In the presence of the amino acid histidine, an inorganic-organic hybrid metal sulfite, Zn2(SO3)2(C6N3O2H9)2·H2O (1), has been prepared under hydrothermal conditions. Single-crystal X-ray diffraction analysis reveals that 1 shows a 2D layer framework built up from a classical second building unit (S4R), and bridged histidine molecule. Notably, it is the first report of a metal sulfite in the presence of an amino acid molecule. A 1D H-bonding array can be constructed by the H-bonding interaction between histidine molecules and sulfite groups. Moreover, a new function of metal sulfite for proton conduction was investigated by alternating-current impedance analysis. The results demonstrate that compound 1 shows a high proton conductivity of approximately 10-3 S cm-1 at 348 K and 98% relative humidity.

Curcumin analog EF24 induces apoptosis and downregulates the mitogen activated protein kinase/extracellular signal-regulated signaling pathway in oral squamous cell carcinoma.

Oral squamous cell carcinoma (OSCC) is one of the most common malignancies worldwide. Diphenyldifluoroketone (EF24) is a curcumin analog that has been demonstrated to improve anticancer activity; however, its therapeutic potential and mechanisms in oral cancer remain unknown. In the present study, the effect of EF24 on apoptosis induction and its potential underlying mechanism in the CAL­27 human OSCC cell line was investigated. To achieve this, various concentrations of cisplatin or EF24 were administrated to CAL­27 cells for 24 h, and cell viability, apoptotic DNA fragmentation, and cleaved caspase 3 and 9 levels were evaluated. To investigate the potential underlying mechanism, the levels of mitogen­activated protein kinase kinase 1 (MEK1) and extracellular signal­regulated kinase (ERK), two key proteins in the mitogen­activated protein kinase/ERK signaling pathway, were additionally examined. The results indicated that EF24 and cisplatin treatment decreased cell viability. EF24 treatment increased the levels of activated caspase 3 and 9, and decreased the phosphorylated forms of MEK1 and ERK. Sequential treatments of EF24 and 12­phorbol­13­myristate acetate, a MAPK/ERK activator, resulted in a significant increase of activated MEK1 and ERK, and reversed cell viability. These results suggested that EF24 has potent anti­tumor activity in OSCC via deactivation of the MAPK/ERK signaling pathway. Further analyses using animal models are required to confirm these findings in vivo.

Functional role of arginine 425 in the mammalian Na⁺/H⁺ exchanger.

Na(+)/H(+) exchanger isoform 1 (NHE1) is the principal plasma membrane Na(+)/H(+) exchanger of mammalian cells and functions by exchanging one intracellular proton for one extracellular sodium ion. Critical transmembrane segments of Na(+)/H(+) exchangers have discontinuous transmembrane helices, which result in a dipole within the membrane. Amino acid R425 has been suggested to play an important role in neutralizing one such helix dipole. To investigate this hypothesis, R425 was mutated to alanine, glutamine, histidine, or lysine and the mutant NHE1 proteins were expressed and characterized in NHE1-deficient cells. The R425A and R425E mutants exhibited complete loss of expression of mature, fully glycosylated NHE1, reduced expression overall, and greatly reduced cell surface targeting. The cell surface targeting, expression, and activity of the R425H and R425K mutant proteins were also impaired, though residual NHE1 activity remained. When reduced targeting and expression were accounted for, the R425H and R425K mutant proteins had activity similar to that of the wild-type protein. The results suggest that R425 is critical for NHE1 expression, targeting, and activity and that replacement with another basic residue can rescue activity. The findings are consistent with a role for R425 in both neutralizing a helix dipole and maintaining NHE1 structure and function.

Characterization of human mutations in phosphorylatable amino acids of the cytosolic regulatory tail of SLC9A1.

The NHE1 isoform of the mammalian Na(+)/H(+) exchanger is a ubiquitous plasma membrane protein that regulates intracellular pH in cells by removing one intracellular proton in exchange for one extracellular sodium. Genetic defects in NHE1 have been shown to affect the growth and motor ability of mice, but mutations in humans have not been studied. NHE1 has a cytosolic C-terminal regulatory domain of approximately 300 amino acids. We investigated the functional effects of two human mutations found in the regulatory phosphorylatable amino acids Ser(703) and Ser(771). A Ser703Pro mutant protein had essentially the same activity, expression, and targeting as the wild type NHE1 protein. In contrast, the Ser771Pro protein had reduced activity and expression of NHE1 protein, though cell surface targeting was normal. In dual pulse assays the Ser771Pro mutant was not further activated by sustained intracellular acidosis but displayed an unusual activation by brief pulses of acidosis. The results demonstrate that the Ser771Pro human genetic mutation has significant and detrimental physiological effects on the activity of the NHE1 protein, SLC9A1.

Distraction osteogenesis after irradiation in rabbit mandibles.

The aim of this study was to investigate the influence of irradiation on the formation of bone after distraction osteogenesis in rabbit mandibles. Sixteen rabbits were randomly divided into 3 groups: one was given 50Gy (n=6), one was given 60Gy (n=6), and one acted as a control group (n=4). One month after irradiation, the distractors were inserted. The control group was not irradiated. After a latency period of 8 days, distraction was activated at a rate of 0.4mm twice a day. The mandibles were harvested 6 weeks after consolidation. The specimens and histological examination showed good formation of bone. Histological slides stained with haematoxylin and eosin confirmed that the regeneration was bone. The bony trabeculae of the control group were much better than those of the irradiated groups. However, the nuclei of osteocytes were round and the osteoblasts around the trabeculae were columnar or cubic in shape in the irradiated groups. Osteoid was present in the dense fibrous connective tissue. There were significant differences in the surface:volume ratio of areas of bony trabeculae between the control and both experimental groups (p=0.010 and p=0.001), but there was no significant difference between the 50Gy and 60Gy groups. The results suggested that preoperative radiation prevented optimal regeneration of bone. However, the microscopic appearance of osteocytes and osteoblasts and the osteoid in the dense fibrous connective tissue in both irradiated groups showed that osteogenesis was still active and in progress. These findings may indicate that bone formation had only been delayed. The evidence was similar for both 50Gy and 60Gy.

[Infections of the head and neck leading to descending necrotizing mediastinitis: management of 9 cases].

OBJECTIVE: To report nine cases of descending necrotizing mediastinitis (DNM) and to summarize the management experience. METHODS: Between December 2005 and December 2008, nine patients (mean age, 55.7 years; age range, 38 to 78 years) with DNM were treated. Eight patients underwent surgical drainage of the involved cervical region and mediastinum (4 with cervical drainage alone; 4 with cervical drainage and right thoracotomy). RESULTS: Two patients died, one of them refused surgical therapy and the other one died of multiorgan failure related to postoperative septic shock. Seven patients recovered. The mortality rate was 22%. CONCLUSIONS: Delayed diagnosis and inadequate drainage are the main causes of high mortality rate of DNM. Aggressive surgical drainage and debridement of the neck and mediastinum by a multidisciplinary team of surgeons are very important in the treatment of DNM.

[Experimental study on the reconstruction of mandibular symphyseal defects by internal tri-focal distractor].

OBJECTIVE: To introduce the internal tri-focal distractor developed by the authors and evaluate its primary application and feasibility in animal experiment. METHODS: Four hybrid dogs were selected and segmental resection at the mandibular symphysis was performed. Two transfer disks, 10 mm in width, were respectively fixed at the two ends of bone defect and the internal tri-focal distractor was installed. The force was applied one week after the operation, with a tractive speed of 0.5 mm/12 h. After 13 - 16 days, the traction was completed when the two transfer disks were combined. The occlusal films were taken at the 1st day, 4th, 8th and 12th week after traction. The animals were killed at the 12th week, samples of the traction area taken and histological examination performed. Finally, the new bone formation was observed. RESULTS: All the animals survived in the experiment, abruption and rust-eaten was not found in distractor. In the 12th week after installation, new bones in traction gap were mature and bony union between the two transfer dishes was accomplished. CONCLUSIONS: The internal tri-focal distractor used in this study may become a potential device in reconstruction of mandibular symphyseal defects.

[Distraction osteogenesis for treatment of unilateral temporomandibular joint ankylosis and secondary OSAHS in children: report of 4 cases].

PURPOSE: To evaluate the efficiency of distraction osteogenensis for treatment of unilateral temporomandibular joint ankylosis and secondary OSAHS in children. METHODS: 4 children with temporomandibular joint ankylosis and secondary OSAHS were retrospectively reviewed for their treatment. There were 2 males and 2 females, ranging from 5 to 13 years in age with the median of 6.5 years. Based on the history of the disease, the clinical manifestations, CT scan and PSG findings, the diagnosis was confirmed to be unilateral temporomandibular joint ankylosis and secondary OSAHS. All the patients were treated by gap arthroplasty to restore mouth opening, combined with mandibular body distraction osteogenesis for treatment of OSAHS. One-stage operation was performed on 3 patients, and two-stage operation on 1 patient. Unilateral and bilateral mandibular distraction osteogenesis was undergone on 2 patients individually. At the end of consolidation period of 3 months, the PSG examination was performed again and the distractor was removed. RESULTS: OSAHS was cured, the average AHI was lowered from 42.7 to 4.9, the average lowest saturation of blood oxygen rose from 74.3% to 89.8%, the average incisor distance reached 25.5mm compared to 6.5mm before surgery and facial deformity was corrected satisfactorily. Following up 38.1 months (13-58 months), no relapse appeared. CONCLUSION: Mandibular body distraction osteogenesis, combined with gap arthroplasty, could be the potential treatment modality for children with unilateral temporomandibular joint ankylosis, secondary OSAHS and facial asymmetry; it is recommended that both procedures be performed at the same time.