[Short-term outcomes of all-inside endoscopic running locked stitch technique for acute achilles tendon ruptures]

Objective: To evaluate the short-term outcomes of all-inside endoscopic running locked stitch technique for acute Achilles tendon ruptures. Methods: This is a retrospective case series study. Forty cases with acute Achilles tendon rupture were treated with the all-inside endoscopic running locked stitch technique from April 2020 to March 2022. There were 44 males and 4 females, aged (34.8±7.4) years (range: 24 to 50 years). Body mass index was (21.2±2.4)kg/m2 (range: 18 to 26 kg/m2); There were 29 cases (60.4%) on the left side and 19 cases (39.6%) on the right side. Under endoscopic control, the proximal tendon stumps were stitched with the running locked method using a semi-automatic flexible suture passer. The threads of the high-strength suture were grasped through the paratenon sub-space and then fixed into calcaneal insertion with a knotless anchor. MRI of Achilles tendon, surgical time and complications were assessed. Achilles tendon total rupture score (ATRS), Achilles tendon resting angle, and heel rise height scale were utilized to evaluate final clinical outcomes. The differences of bilateral limbs were compared using the paired t test. Results: The follow-up time was (24.1±3.5)months (range:18 to 32 months). Appropriate tendon regeneration was observed on MRI at post-operative 12 months. The median ATRS score (M(IQR)) was 95.0 (4.7) points. Furthermore, there was no significant difference between the injured and contralateral side in the Achilles tendon resting angle ((17.1±2.4)° vs. (17.4±2.6)°, t=1.92,P=0.062) and heel rise height ((14.2±1.7)cm vs. (14.4±1.5)cm, t=1.71,P=0.094). No nerve injuries, infection, deep vein thrombosis and re-ruptures were encountered. Sports activity resumed six months postoperative in 46 patients. One patient had a slight anchor cut-out, due to an addition injury, which was removed after 5 months. Conclusions: All-inside endoscopic running locked stitch technique for acute Achilles tendon ruptures shows promising results. It provides stable connection of the tendon stumps with a low risk of complications.

[Effect of SLC7A11 gene downregulation on the gefitinib resistance of lung adenocarcinoma PC9/GR cells and its mechanism]

Objective: To screen the key genes involved in gefitinib resistance of lung adenocarcinoma PC9/GR cells which harbored 19 exon mutation of epidermal growth factor receptor (EGFR) gene, and discuss the effect and mechanism of downregulation of solute carrier family 7 member 11 (SLC7A11) on the gefitinib resistance of PC9/GR cells. Methods: RNA microarray was conducted to detect the gene expressions in PC9 and PC9/GR cells. The differently expressed genes were screened by using limma package of R language and analyzed by Kyoto encyclopedia of genes and genomes (KEGG) pathway enrichment analysis. Western blotting was performed to determine the expression of SLC7A11 protein in PC9 and PC9/GR cells. PC9/GR cells were infected with lentivirus plasmid containing short hairpin RNA (shRNA) targeting SLC7A11 or negative control shRNA (sh-NC), respectively. Real-time quantitative polymerase chain reaction (RT-qPCR) was performed to evaluate the efficacy of shRNA on the expression of SLC7A11 mRNA. Cell counting kit-8 (CCK-8) assay was conducted to determine the suppressing effect of gefitinib on PC9/GR cells. Mito-Tracker Red CMXRos probe and malondialdehyde (MDA) assay kit were used to evaluate gefitinib-induced ferroptosis in PC9/GR cells. Immunohistochemistry (IHC) was conducted to detect the expression of SLC7A11 protein in the tumor tissues of advanced stage lung adenocarcinoma patients harboring 19 exon mutation of EGFR gene. Thirty-six advanced stage lung adenocarcinoma patients who received EGFR-tyrosihe kinase inhibitor(TKI) as first-line treatment in Fourth Hospital of Hebei Medical Unviersity were enrolled. Kaplan-Meier survival curve was drawn to analyze the correlation between SLC7A11 expression and progression-free survival (PFS) of the patients. Results: RNA array demonstrated that 2 888 genes were differently expressed between PC9 and PC9/GR cells. KEGG analysis showed that ferroptosis-related gene was one of the most enriched region of the differently expressed genes between PC9 and PC9/GR cells. These ferroptosis-related gene cohort contained 13 genes, among which SLC7A11 exhibited the most significant difference. Western blotting showed that the expression of SLC7A11 protein in PC9/GR cells was significantly higher than that in PC9 cells (0.76±0.03 vs. 0.19±0.02, P<0.001). The 50% inhibiting concentration (IC(50)) of gefitinib was 35.08 μmol/L and 64.01 μmol/L for sh-SLC7A11 and sh-NC group PC9/GR cells, respectively. PC9/GR cells in sh-SLC7A11 group exhibited significantly lower density of mitochondria fluorescence after gefitinib treatment, compared to the sh-NC group (213.77±26.50 vs. 47.88±4.55, P<0.001). In addition, PC9/GR cells in sh-SLC7A11 group exhibited significantly higher MDA after gefitinib treatment, compared to the sh-NC group [(15.43±1.60) μmol/mg vs. (82.18±7.77) μmol/mg, P<0.001]. The PFS of the patients with low expression of SLC7A11 (n=18) was significantly longer than the patients with high expression of SLC7A11 (n=18, 16.77 months vs. 9.14 months, P<0.001). Conclusion: Downregulation of SLC7A11 could increase the sensitivity of PC9/GR cells to gefitinib by promoting ferroptosis.

A proof of concept for neutralizing antibody-guided vaccine design against SARS-CoV-2

Mutations and transient conformational movements of the receptor binding domain (RBD) that make neutralizing epitopes momentarily unavailable present immune escape routes for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). To mitigate viral escape, we developed a cocktail of neutralizing antibodies (NAbs) targeting epitopes located on different domains of spike (S) protein. Screening of a library of monoclonal antibodies generated from peripheral blood mononuclear cells of COVID-19 convalescent patients yielded potent NAbs, targeting the N-terminal domain (NTD) and RBD domain of S, effective at nM concentrations. Remarkably, a combination of RBD-targeting NAbs and NTD-binding NAbs, FC05, enhanced the neutralization potency in cell-based assays and an animal model. Results of competitive surface plasmon resonance assays and cryo-electron microscopy (cryo-EM) structures of antigen-binding fragments bound to S unveil determinants of immunogenicity. Combinations of immunogens, identified in the NTD and RBD of S, when immunized in rabbits and macaques, elicited potent protective immune responses against SARS-CoV-2. More importantly, two immunizations of this combination of NTD and RBD immunogens provided complete protection in macaques against a SARS-CoV-2 challenge, without observable antibody-dependent enhancement of infection. These results provide a proof of concept for neutralization-based immunogen design targeting SARS-CoV-2 NTD and RBD.

Aberration corrections for free-space optical communications in atmosphere turbulence using orbital angular momentum states

The effect of atmosphere turbulence on light's spatial structure compromises the information capacity of photons carrying the Orbital Angular Momentum (OAM) in free-space optical (FSO) communications. In this paper, we study two aberration correction methods to mitigate this effect. The first one is the Shack-Hartmann wavefront correction method, which is based on the Zernike polynomials, and the second is a phase correction method specific to OAM states. Our numerical results show that the phase correction method for OAM states outperforms the Shark-Hartmann wavefront correction method, although both methods improve significantly purity of a single OAM state and the channel capacities of FSO communication link. At the same time, our experimental results show that the values of participation functions go down at the phase correction method for OAM states, i.e., the correction method ameliorates effectively the bad effect of atmosphere turbulence.

Detection of adeno-associated virus type 2 genome in cervical carcinoma

Adeno-associated virus (AAV) can impair the replication of other viruses. Adeno-associated virus seroprevalences have been reported to be lower among women with cervical cancer. In-vitro, AAV can interfere with the production of human papillomavirus virions. Adeno-associated virus-2 DNA has also been detected in cervical cancer tissue, although not consistently. To evaluate the role of AAV infection in relation to invasive cervical cancer, we performed a nested case–control study within a retrospectively followed population-based cohort. A total of 104 women who developed invasive cervical cancer on average 5.6 years of follow-up (range: 0.5 months–26.2 years) and 104 matched control-women who did not develop cervical cancer during the same follow-up time were tested for AAV and human papillomavirus by polymerase chain reaction. At baseline, two (2%) case-women and three (3%) control-women were positive for AAV-2 DNA. At the time of cancer diagnosis, 12 (12%) case-women and 3 (3%) matched control-women were positive for AAV-2 DNA. Persisting AAV infection was not evident. In conclusion, AAV-2 DNA was present in a low proportion of cervical cancers and we found no evidence that the presence of AAV in cervical smears of healthy women would be associated with reduced risk of cervical cancer.

Effect of perfusion of oral rehydration solutions containing glucose polymers from corn on disaccharidases and mucosal morphology in rat small intestines

This study aims to determine the effect of glucose and glucose polymers (GP) from corn in oral rehydration solutions (ORS) on disaccharidases and morphometric measurements in small intestinal mucosa of rats. ORS containing standard composition of salts as in WHO ORS and 2, 5, or 10 per cent glucose or GP [initial glucose polymers, long chain (> 9 molecules) and short chain (2-9 molecules) glucose polymers] from corn were infused into the duodenum of 72 Sprague-Dawley rats (250-350 g). Six rats were sham operated as controls. The levels of lactase, sucrase, maltase, palatinase, and glucoamylase enzymes were higher in rats infused with ORS-containing glucose or GP than control rats. Villus height, villus width, and crypt height in corresponding segments of duodenum, jejunum, and ileum were not significantly different between rats perfused with ORS containing glucose polymers from corn and those with ORS containing glucose. ORS containing GP from corn have no adverse effects on small intestinal enzymes and morphometric measurements.

Small intestinal glucoamylase deficiency and starch malabsorption: a newly recognized alpha-glucosidase deficiency in children

To determine the prevalence of short polymers of glucose and starch malabsorption caused by small intestinal glucoamylase deficiency in children with chronic diarrhea, we studied small bowel biopsy specimens from 511 children (aged 1 month to 9 years) with chronic diarrhea evaluated at 54 medical centers. Glucoamylase and disaccharidase (lactase, sucrase, maltase, and palatinase) enzyme assays were performed. Of the 511 children, 15 had glucoamylase deficiency. Six who had significant small intestinal mucosal injury and disaccharidase deficiencies were defined as having secondary glucoamylase deficiency; the other nine patients with normal mucosal morphologic features were defined as having primary glucoamylase deficiency. Secretin tests showed normal pancreatic amylase values for age in all seven children tested. Four of them had abnormal findings on tolerance tests for starch and short polymers of glucose (rise in blood glucose concentration: < 20 mg/dl) and reducing substances in stools, and three of these four had symptoms of intolerance (abdominal distention, flatulence, and diarrhea). All seven patients responded to a starch elimination diet. After reintroduction of a starch diet, diarrhea recurred in four patients; this was alleviated 48 hours after reelimination of starch. We conclude that intestinal glucoamylase deficiency is present in some patients with chronic diarrhea.

Absorption of glucose polymers from rice in oral rehydration solutions by rat small intestine

BACKGROUND

This study aims to determine the effect of replacing glucose in oral rehydration solution (ORS) with starch hydrolysates from rice on absorption in the small intestine and levels of glucose in portal venous blood and on disaccharidase levels and morphometric measurements in intestines of rats.

METHODS

ORS containing standard composition of salts and 2% glucose (WHO ORS) or 2%, 5%, or 10% starch hydrolysates were infused into duodena of 60 Sprague-Dawley rats (250-350 g). Portal venous blood glucose levels were determined at 0, 30, 60, 90, and 120 minutes.

RESULTS

Significantly larger areas under the curve of glucose absorption (AUCs) were produced by ORS containing 10% unfractionated starch hydrolysates (123.2 +/- 3.8), 2%, 5%, and 10% starch hydrolysates with long-chain ( > 9 molecules) glucose polymers (109.5 +/- 10.6, 109.3 +/- 7.4, and 115.3 +/- 7.1, respectively), and 5% and 10% starch hydrolysates with short-chain (2-9 molecules) glucose polymers (124.4 +/- 6.1 and 128.1 +/- 6.8). ORS with 2% and 5% unfractionated starch hydrolysates and 2% short-chain glucose polymers produced AUCs comparable with those of WHO ORS (96.48 +/- 5.7). Disaccharidase levels and morphometric measurements were not significantly different.

CONCLUSIONS

Starch hydrolysates from rice containing glucose polymers can be used in ORS in higher concentrations than glucose to provide higher caloric density without increased osmolality.

An optimal rice-based oral rehydration solution: the effect of different concentrations of amylase on production of short chain polymers of glucose

As part of a plan to develop a rice-based oral rehydration solution containing short polymers of glucose instead of glucose, we determined the concentration of amylase that would yield the largest amount of short chain polymers. Thai rice (25 g) was boiled with 500 ml of distilled water for 30 min. Of 200 ml supernatant rice water obtained, 100 ml were digested with different amounts of amylase after cooling to 50 degrees C for 60 min, boiled for 5 min, and centrifuged (10,000 g, 25 degrees C) for 60 min. The resulting supernatant (80 ml) was freeze-dried; 1.75 g of the powder obtained were dissolved in 3.5 ml of water, passed through a Bio-Gel P2 column to separate short chain polymers (2-9 molecules of glucose) and long chain polymers (> 9 molecules of glucose), which were identified by spectrophotometry (lambda = 190 nm) or by high performance liquid chromatography. Ten mg of amylase (equivalent to 12,000 modified Wohlgemath units) per 100 ml of rice water was optimal for the production of short polymers of glucose from rice.