ThermomiR-377-3p-induced suppression of Cirbp expression is required for effective elimination of cancer cells and cancer stem-like cells by hyperthermia.

BACKGROUND: In recent years, the development of adjunctive therapeutic hyperthermia for cancer therapy has received considerable attention. However, the mechanisms underlying hyperthermia resistance are still poorly understood. In this study, we investigated the roles of cold­inducible RNA binding protein (Cirbp) in regulating hyperthermia resistance and underlying mechanisms in nasopharyngeal carcinoma (NPC). METHODS: CCK-8 assay, colony formation assay, tumor sphere formation assay, qRT-PCR, Western blot were employed to examine the effects of hyperthermia (HT), HT + oridonin(Ori) or HT + radiotherapy (RT) on the proliferation and stemness of NPC cells. RNA sequencing was applied to gain differentially expressed genes upon hyperthermia. Gain-of-function and loss-of-function experiments were used to evaluate the effects of RNAi-mediated Cirbp silencing or Cirbp overexpression on the sensitivity or resistance of NPC cells and cancer stem-like cells to hyperthermia by CCK-8 assay, colony formation assay, tumorsphere formation assay and apoptosis assay, and in subcutaneous xenograft animal model. miRNA transient transfection and luciferase reporter assay were used to demonstrate that Cirbp is a direct target of miR-377-3p. The phosphorylation levels of key members in ATM-Chk2 and ATR-Chk1 pathways were detected by Western blot. RESULTS: Our results firstly revealed that hyperthermia significantly attenuated the stemness of NPC cells, while combination treatment of hyperthermia and oridonin dramatically increased the killing effect on NPC cells and cancer stem cell (CSC)­like population. Moreover, hyperthermia substantially improved the sensitivity of radiation­resistant NPC cells and CSC­like cells to radiotherapy. Hyperthermia noticeably suppressed Cirbp expression in NPC cells and xenograft tumor tissues. Furthermore, Cirbp inhibition remarkably boosted anti­tumor­killing activity of hyperthermia against NPC cells and CSC­like cells, whereas ectopic expression of Cirbp compromised tumor­killing effect of hyperthermia on these cells, indicating that Cirbp overexpression induces hyperthermia resistance. ThermomiR-377-3p improved the sensitivity of NPC cells and CSC­like cells to hyperthermia in vitro by directly suppressing Cirbp expression. More importantly, our results displayed the significantly boosted sensitization of tumor xenografts to hyperthermia by Cirbp silencing in vivo, but ectopic expression of Cirbp almost completely counteracted hyperthermia-mediated tumor cell-killing effect against tumor xenografts in vivo. Mechanistically, Cirbp silencing-induced inhibition of DNA damage repair by inactivating ATM-Chk2 and ATR-Chk1 pathways, decrease in stemness and increase in cell death contributed to hyperthermic sensitization; conversely, Cirbp overexpression-induced promotion of DNA damage repair, increase in stemness and decrease in cell apoptosis contributed to hyperthermia resistance. CONCLUSION: Taken together, these findings reveal a previously unrecognized role for Cirbp in positively regulating hyperthermia resistance and suggest that thermomiR-377-3p and its target gene Cirbp represent promising targets for therapeutic hyperthermia.

Transcriptome sequencing and experiments reveal the effect of formyl peptide receptor 2 on liver homeostasis.

BACKGROUND: Formyl peptide receptor 2 (Fpr2) is an important receptor in host resistance to bacterial infections. In previous studies, we found that the liver of Fpr2-/- mice is the most severely damaged target organ in bloodstream infections, although the reason for this is unclear. AIM: To investigate the role of Fpr2 in liver homeostasis and host resistance to bacterial infections. METHODS: Transcriptome sequencing was performed on the livers of Fpr2-/- and wild-type (WT) mice. Differentially expressed genes (DEGs) were identified in the Fpr2-/- and WT mice, and the biological functions of DEGs were analyzed by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) en-richment analysis. Quantitative real time-polymerase chain reaction (qRT-PCR) and western blot (WB) analyses were used to further validate the expression levels of differential genes. Cell counting kit-8 assay was employed to investigate cell survival. The cell cycle detection kit was used to measure the distribution of cell cycles. The Luminex assay was used to analyze cytokine levels in the liver. The serum biochemical indices and the number of neutrophils in the liver were measured, and hepatic histopathological analysis was performed. RESULTS: Compared with the WT group, 445 DEGs, including 325 upregulated genes and 120 downregulated genes, were identified in the liver of Fpr2-/- mice. The enrichment analysis using GO and KEGG showed that these DEGs were mainly related to cell cycle. The qRT-PCR analysis confirmed that several key genes (CycA, CycB1, Cdc20, Cdc25c, and Cdk1) involved in the cell cycle had significant changes. The WB analysis confirmed a decrease in the expression of CDK1 protein. WRW4 (an antagonist of Fpr2) could inhibit the proliferation of HepG2 cells in a concentration dependent manner, with an increase in the number of cells in the G0/G1 phase, and a decrease in the number of cells in the S phase. Serum alanine aminotransferase levels increased in Fpr2-/- mice. The Luminex assay measurements showed that interleukin (IL)-10 and chemokine (C-X-C motif) ligand (CXCL)-1 levels were significantly reduced in the liver of Fpr2-/- mice. There was no difference in the number of neutrophils, serum C-reactive protein levels, and liver pathology between WT and Fpr2-/- mice. CONCLUSION: Fpr2 participates in the regulation of cell cycle and cell proliferation, and affects the expression of IL-10 and CXCL-1, thus playing an important protective role in maintaining liver homeostasis.

The effect of scrotal versus inguinal orchiopexy on the testicular function of children with clinically palpable, inguinal undescended testis: a randomized controlled trial.

To compare the impact of the scrotal vs inguinal orchidopexy approach on the testicular function of infants with cryptorchidism, a randomized controlled trial was conducted involving boys who were 6-12 months old at surgery and were diagnosed with clinically palpable, inguinal undescended testis. Between June 2021 and December 2021, these boys at Fujian Maternity and Child Health Hospital (Fuzhou, China) and Fujian Children's Hospital (Fuzhou, China) were enrolled. Block randomization with a 1:1 allocation ratio was employed. The primary outcome was testicular function assessed by testicular volume, serum testosterone, anti-Müllerian hormone (AMH), and inhibin B (InhB) levels. Secondary outcomes included operative time, amount of intraoperative bleeding, and postoperative complications. Among 577 screened patients, 100 (17.3%) were considered eligible and enrolled in the study. Of the 100 children who completed the 1-year follow-up, 50 underwent scrotal orchidopexy and 50 underwent inguinal orchidopexy. The testicular volume, serum testosterone, AMH, and InhB levels in both groups increased markedly after surgery (all P < 0.05), but there were no apparent differences between groups at 6 months and 12 months after operation (all P > 0.05). No differences between the scrotal and inguinal groups were noted regarding the operative time ( P = 0.987) and amount of intraoperative bleeding ( P = 0.746). The overall complication rate (2.0%) of the scrotal group was slightly lower than that of the inguinal group (8.0%), although this difference was not statistically significant ( P > 0.05). Both scrotal and inguinal orchiopexy exerted protective effects on testicular function in children with cryptorchidism, with similar operative status and postoperative complications. Scrotal orchiopexy is an effective alternative to inguinal orchiopexy in children with cryptorchidism.

Effect of pneumovesicoscopic cohen surgery with adjustable suspension technique through the urethra on the treatment of primary vesicoureteral reflux disease in infants.

OBJECTIVE: The objective of this study was to evaluate the safety and efficacy of pneumovesicoscopic Cohen surgery with an adjustable suspension technique through the urethra for the treatment of primary vesicoureteral reflux disease in infants. METHODS: This study retrospectively analysed the clinical data of 31 infants who underwent pneumovesicoscopic Cohen surgery with an adjustable suspension technique through the urethra in our hospital from January 2019 to December 2020. We also collected the clinical data of 29 infants who underwent open Cohen surgery in our hospital from January 2015 to December 2018 as a control variable. The clinical efficacy of the two groups was compared. RESULT: All pneumovesicoscopic Cohen surgeries were successfully completed and no patients were converted to open surgery. The amount of bleeding, duration of postoperative analgesia, duration of postoperative haematuria, incision size and length of hospital stay in the pneumovesicoscopic surgery group were significantly lower than those in the open surgery group (P < 0.05). The operation time of the pneumovesicoscopic surgery group was significantly longer than that of the open surgery group (P < 0.05). Both groups were followed for six months after surgery. At the 6-month follow-up time, there were no significant differences in the degree of hydronephrosis, renal scarring, renal atrophy, glomerular filtration rate, or KIM-1 and MCP-1 expression between the two groups (P > 0.05). CONCLUSION: Pneumovesicoscopic Cohen surgery with an adjustable suspension technique through the urethra for the treatment of primary vesicoureteral reflux disease in infants was safe and effective. This procedure had the advantages of less trauma, quick recovery and good cosmetic effects.

Identification of m6a-related signature genes in esophageal squamous cell carcinoma by machine learning method.

Background: We aimed to construct and validate the esophageal squamous cell carcinoma (ESCC)-related m6A regulators by means of machine leaning. Methods: We used ESCC RNA-seq data of 66 pairs of ESCC from West China Hospital of Sichuan University and the transcriptome data extracted from The Cancer Genome Atlas (TCGA)-ESCA database to find out the ESCC-related m6A regulators, during which, two machine learning approaches: RF (Random Forest) and SVM (Support Vector Machine) were employed to construct the model of ESCC-related m6A regulators. Calibration curves, clinical decision curves, and clinical impact curves (CIC) were used to evaluate the predictive ability and best-effort ability of the model. Finally, western blot and immunohistochemistry staining were used to assess the expression of prognostic ESCC-related m6A regulators. Results: 2 m6A regulators (YTHDF1 and HNRNPC) were found to be significantly increased in ESCC tissues after screening out through RF machine learning methods from our RNA-seq data and TCGA-ESCA database, respectively, and overlapping the results of the two clusters. A prognostic signature, consisting of YTHDF1 and HNRNPC, was constructed based on our RNA-seq data and validated on TCGA-ESCA database, which can serve as an independent prognostic predictor. Experimental validation including the western and immunohistochemistry staining were further successfully confirmed the results of bioinformatics analysis. Conclusion: We constructed prognostic ESCC-related m6A regulators and validated the model in clinical ESCC cohort as well as in ESCC tissues, which provides reasonable evidence and valuable resources for prognostic stratification and the study of potential targets for ESCC.

Subset-specific Retention of Donor Myeloid Cells After Major Histocompatibility Complex-matched and Mismatched Liver Transplantation.

BACKGROUND: During solid organ transplantation, donor leukocytes, including myeloid cells, are transferred within the organ to the recipient. Both tolerogenic and alloreactive roles have been attributed to donor myeloid cells; however, their subset-specific retention posttransplantation has not been investigated in detail. METHODS: Major histocompatibility complex (MHC)-matched and mismatched liver transplants were performed in mice, and the fate of donor and recipient myeloid cells was assessed. RESULTS: Following MHC-matched transplantation, a proportion of donor myeloid cells was retained in the graft, whereas others egressed and persisted in the blood, spleen, and bone marrow but not the lymph nodes. In contrast, after MHC-mismatched transplantation, all donor myeloid cells, except Kupffer cells, were depleted. This depletion was caused by recipient T and B cells because all donor myeloid subsets were retained in MHC-mismatched grafts when recipients lacked T and B cells. Recipient myeloid cells rapidly infiltrated MHC-matched and, to a greater extent, MHC-mismatched liver grafts. MHC-mismatched grafts underwent a transient rejection episode on day 7, coinciding with a transition in macrophages to a regulatory phenotype, after which rejection resolved. CONCLUSIONS: Phenotypic and kinetic differences in the myeloid cell responses between MHC-matched and mismatched grafts were identified. A detailed understanding of the dynamics of immune responses to transplantation is critical to improving graft outcomes.

A modified fixation technique for the treatment of buried penis in children.

For many years, surgical treatment of buried penis in children has been researched by several scholars, and numerous methods exist. This study aimed to explore the clinical effect of a modified fixation technique in treating buried penis in children. Clinical data of 94 patients with buried penis who were treated using the modified penile fixation technique from March 2017 to February 2019 in Fujian Maternity and Child Health Hospital (Fuzhou, China) were retrospectively collected, compared, and analyzed. Clinical data of 107 patients with buried penis who were treated using traditional penile fixation technique from February 2014 to February 2017 were chosen for comparison. The results showed that at 6 months and 12 months after surgery, the penile lengths in the modified penile fixation group were longer than those in the traditional penile fixation group (both P < 0.05). The incidence of postoperative skin contracture and penile retraction in the modified penile fixation group was less than that in the traditional penile fixation group (P = 0.034 and P = 0.012, respectively). When the two groups were compared in terms of parents' satisfaction scores, the scores for penile size, penile morphology, and voiding status in the modified penile fixation group were higher than those in the traditional penile fixation group at 2-week, 6-month, and 12-month follow-ups after surgery (all P < 0.05). We concluded that the modified penile fixation technique could effectively reduce the incidence of skin contracture and penile retraction and improve the penile length and satisfaction of patients' parents.

Current Genetic Structure Analysis of Leopard Cats Reveals a Weak Disparity Trend in Subpopulations in Beijing, China.

In the face of habitat shrinkage and segregation, the survival of wild cats looks bleak. Interpreting their population genetic structure during habitat fragmentation is critical in planning effective management strategies. To reveal the segregation effects of road construction and human settlements on the population genetic structure, we analyzed non-invasive fecal DNA samples from leopard cats (Prionailurus bengalensis) from five nature reserves in mountainous areas around Beijing. We focused on microsatellite markers. A total of 112 individual leopard cats were identified among 601 samples of scat, and moderate population genetic diversity was detected. Microsatellite-marker-based genetic differentiation (Fst) and gene flow (Nm) showed a weak trend toward discrepancies in the Baihuashan and Songshan subpopulations, which indicated habitat fragmentation effects on individual dispersal. Because the segregated subpopulations may suffer a high risk of genetic diversity loss, we suggest that their genetic structure be monitored with more molecular markers to detect any changes, and that female individuals be artificially introduced as needed to maintain the viability of the leopard cat subpopulations in Beijing.

A Modified Murine Heterotopic Heart Transplant Protocol Matching Contemporary Standards of Aseptic Technique, Anesthesia, and Analgesia.

The development of experimental models of cardiac transplantation in animals has contributed to many advances in the fields of immunology and solid organ transplantation. While the heterotopic vascularized murine cardiac transplantation model was initially utilized in studies of graft rejection using combinations of mismatched inbred mouse strains, access to genetically modified strains and therapeutic modalities can provide powerful new preclinical insights. Fundamentally, the surgical methodology for this technique has not changed since its development, especially with respect to important factors such as aseptic technique, anesthesia, and analgesia, which make material impacts on postsurgical morbidity and mortality. Additionally, improvements in perioperative management are expected to provide improvements in both animal welfare and experimental outcomes. This paper reports upon a protocol developed in collaboration with a subject matter expert in veterinary anesthesia and describes the surgical technique with an emphasis on perioperative management. Additionally, we discuss the implications of these refinements and provide details on troubleshooting critical surgical steps for this procedure.

Bonding wire interconnection de-embedding for GaN high electron mobility transistor loadpull measurement with fixture.

Test fixtures with high power capacity and an impedance matching network are generally chosen for measurements of high-power gallium nitride high electron mobility transistors. To make interconnection of the test fixtures and devices under test, wire bonding is an effective assembly method. Bonding wires become dominant parasitic elements, especially in the S parameter measurement and loadpull measurement, which should be taken into account and accurately de-embedded for device measurements and modeling. In this paper, test fixtures and through-reflect-line calibration kits are designed to achieve the S parameter measurements of the bonding wire with a vector network analyzer. Equivalent inductances of the bonding wire can be obtained with the electromagnetic simulation model and compact circuit model proposed based on the test fixture. The good agreement of the equivalent inductances extracted with the test fixture and models verified that the way to characterize bonding wire interconnection is effective and accurate. Cree's CGHV1J006D is chosen to take the S parameter measurement for proving the accurate model of the bonding wire. Finally, the equivalent inductance of the 2 mm gate-width transistor is obtained with the electromagnetic model. The drain impedance is accurately calculated after the loadpull measurement with bonding wire effects de-embedded, which matches the loadline theory.

Mini-laparoscopic pyeloplasty to treat UPJO in infants.

PURPOSE: The aim of this study was to investigate the safety and clinical efficacy of mini-laparoscopic pyeloplasty in treating ureteropelvic junction obstruction (UPJO) in infants. MATERIAL AND METHODS: We retrospectively analysed the clinical data of 66 infants with UPJO from January 2013 to August 2018 at our hospital. They were divided into the laparoscopic surgery group (group A) and the open surgery group (group B), depending on the surgical method. RESULTS: The bleeding volume, analgesia duration, postoperative hospitalization duration, and incision length in group A were significantly less than those in group B (p < .05). The incidence of incision dehiscence was 0% in group A and 11.7% in group B (p = .045). At the postoperative follow-up, the incidence of anastomotic stenosis was 6.2% in group A and 5.9% in group B (p = .719). The anteroposterior diameter and glomerular filtration rate were significantly improved at the one-year follow-up, but there was no significant difference between the groups (p > .05). CONCLUSIONS: Mini-laparoscopic pyeloplasty to treat UPJO in infants has the same early clinical efficacy and safety as open surgery, and this procedure has the advantages of fewer incisions, less pain, quicker recovery, and better cosmetic outcomes.

Single-port laparoscopic percutaneous closure of the internal ring for scarless repair of inguinal hernias in girls.

PURPOSE: The purpose of this study was to summarize the clinical experience with laparoscopic percutaneous extraperitoneal closure of the internal ring using an epidural needle for inguinal hernias in girls. MATERIAL AND METHODS: A total of 462 girls with inguinal hernias participated in this study from January 2013 to June 2019. Laparoscopic percutaneous extraperitoneal closure of the internal ring via an epidural needle was used to treat these patients. RESULTS: All 462 girls with an inguinal hernia successfully underwent laparoscopic surgery. The operative times for unilateral and bilateral inguinal hernias were 15 (11-25) minutes and 23 (18-33) minutes, respectively. All patients were discharged 1-2 days after the operations. During the hospitalization and follow-up periods, none of the following complications were observed: hernia recurrence, umbilical hernia, abdominal wall vascular injury, intestinal injury or bladder injury. However, there were six patients with complications: two cases of poor healing of the umbilical incision, three cases of suture granulomas and one case of groin traction pain and discomfort. CONCLUSION: Laparoscopic percutaneous extraperitoneal closure of the internal ring using an epidural needle is a safe and feasible method for the treatment of inguinal hernias in girls. This method has the advantages of limited trauma, no scarring and a good cosmetic effect.

Feasibility of Subtraction Coronary Computed Tomographic Angiography and Influencing Factor Analysis: a Retrospective Study.

OBJECTIVE: To investigate the feasibility of subtraction coronary computed tomographic (CT) angiography (SubCCTA) to decline calcium artifacts and improve diagnostic accuracy in the presence of coronary calcification and analyze the factors that influence SubCCTA. METHODS: A total of 294 patients suspected of having coronary artery diseases underwent coronary computed tomographic angiography (CCTA) and SubCCTA. Coronary stenoses were blindly evaluated by two experienced radiologists, which were compared with invasive coronary angiography (ICA). Multiple statistical indexes were adopted to analyze the value of SubCCTA for the diagnosis of calcium stenoses. RESULTS: The diagnosable rate of SubCCTA was 67.2% (n=197), and the non-diagnosable rate was 32.8% (n=97). Using SubCCTA, the false positive rate decreased from 56.5% to 17.4%, and the corresponding diagnostic accuracy was increased from 83.6% to 92.9%. Univariate logistic regression analysis showed that height (OR=1.029, 95% CI=1.001-1.058), weight (OR=1.025, 95% CI=1.004-1.046), left ventricular size (OR=1.018, 95% CI=1.007-1.030), cardiothoracic ratio (OR=39.917, 95% CI=1.244-1281.098), the average heart rate (OR=0.866, 95% CI=0.836-0.896) and heart rate range (OR=0.882, 95% CI=0.853-0.912) might be the factors influencing SubCCTA. CONCLUSION: This study suggested that SubCCTA could help improve diagnostic accuracy in the presence of calcium plaques. Moreover, several factors were discovered for the first time to possibly influence SubCCTA, which will be helpful in improving the subtracted image quality.

Effect of a Traction Exercise Neck Brace on Cervical Spondylopathy Radiculopathy: A Clinical Study and Finite Element Analysis.

Traction of cervical spine is an effective method for the treatment of cervical spondylotic radiculopathy (CSR). In this study, a cervical tractor named traction exercise neck brace (TENB) was used to evaluate its effect on the patients with CSR. Forty CSR volunteers were recruited and randomly divided into two groups. One group was subjected to cervical muscle exercise with TENB under static traction condition. Another group was subjected to (JOBT) as controls. Symptoms of CSR were evaluated by the visual analogue scale (VAS) and neck disability index (NDI). Imaging characteristics were assessed by curvature of the cervical spine and size of the intervertebral foramen. A finite element (FE) analysis model of cervical spine was established by 3D reconstruction to simulate the TENB traction, which evaluates the biomechanical performance. Results showed that TENB significantly reduced scores of VAS and NDI in subjects, and this improved effect on symptoms of pain and radiculopathy is better than that of JOBT. TENB also improved the cervical curvature and enlarged intervertebral foramen at the C4-C6 level. Moreover, FE analysis found that simulated TENB traction increased the spacing of intervertebral foramen, intervertebral disc, and zygapophyseal and uncovertebral joints and changed the stress distribution on the facet joints and nucleus pulposus. This study demonstrates that TENB relieves the symptoms of CSR by adjusting structure of cervical vertebra and restoring its biomechanical performance, which may be a promising instrument in the treatment of CSR.

Computational numerical analysis of different cannulation methods during cardiopulmonary bypass of type A aortic dissection model based on computational fluid dynamics.

BACKGROUND: The aim of the present study was to use a numerical simulation based on computational fluid dynamics (CFD) to analyze the difference of different cannulation methods on hemodynamics characteristic in a type A aortic dissection (TAAD) model. METHODS: A finite-element analysis based on the CFD model of a TAAD patient was used, and axillary artery cannulation (AAC), innominate artery cannulation (IAC), and femoral artery cannulation (FAC) were analyzed under different situations, including a cardiac output (CO) of 2.5 L/min and cardiopulmonary bypass (CPB) of 2.5 L/min (partial CPB before cross-clamping aorta, defined as condition A), and a CO of 0 L/min and CPB of 5 L/min (aortic cross-clamping phase, defined as condition B). The insertion of an 8-mm cannula into the different models was simulated. Hemodynamic characteristics, including wall shear stress, wall stress, blood flow, and velocity were analyzed. RESULTS: In condition A, the total flow of branches of the aortic arch was 2,009.5 mL/min (AAC), 1,855.47 mL/min (IAC), and 1,648.03 mL/min (FAC). All cannulation methods improved left renal blood perfusion. However, in relation to blood flow in the right renal artery, FAC showed the highest blood flow (105 mL/min). The results in condition B were similar to those of condition A. The velocity, shear stress, and stress of entry tear via AAC and IAC decreased in condition B compared with condition A. The velocity, shear stress, stress of tear via AAC was lower than that of IAC. CONCLUSIONS: Different cannulation modes have an effect on the hemodynamic characteristic of the tear, but this effect is related to different states of CPB. AAC was found to superior to IAC, especially in reducing velocity, stress, and shear stress of site of tear. However, IAC and AAC are more conductive to blood supply than FAC in branch vessels of the aortic arch without being affected by the CPB state.

Dynamic changes to tissue-resident immunity after MHC-matched and MHC-mismatched solid organ transplantation.

The heterogeneous pool of tissue-resident lymphocytes in solid organs mediates infection responses and supports tissue integrity and repair. Their vital functions in normal physiology suggest an important role in solid organ transplantation; however, their detailed examination in this context has not been performed. Here, we report the fate of multiple lymphocyte subsets, including T, B, and innate lymphoid cells, after murine liver and heart transplantation. In major histocompatibility complex (MHC)-matched transplantation, donor lymphocytes are retained in liver grafts and peripheral lymphoid organs of heart and liver transplant recipients. In MHC-mismatched transplantation, increased infiltration of the graft by recipient cells and depletion of donor lymphocytes occur, which can be prevented by removal of recipient T and B cells. Recipient lymphocytes fail to recreate the native organs' phenotypically diverse tissue-resident lymphocyte composition, even in MHC-matched models. These post-transplant changes may leave grafts vulnerable to infection and impair long-term graft function.

Improved measurement techniques for high-power transistor modeling.

Measurement for modeling of the high-power transistors is difficult due to its high-power and low-impedance characteristics. In this paper, novel methods and devices were designed and applied to achieve precise measurements of the high-power transistors. Fixtures capable of withstanding high voltage and current were designed to replace traditional radio frequency (RF) probes for higher power capacity. To reduce the impact of capacitive and inductive components of traditional bias tees on the rising/falling edge, two wideband 90° hybrid couplers that were connected back-to-back were designed for pulsed measurements. The measurement system of stable S-parameters with the Vector Network Analyzer (VNA) was reported, which could protect the devices and laboratory equipment from damage of self-oscillation. Application of several innovative approaches enabled accurate I-V characteristic and S-parameters measurements of high-power transistors in DC or pulsed mode. Experimental results of a 30 W gallium nitride high-electron-mobility transistor verified the validity.

Testicular descent and fixation through a scrotal stria incision for the treatment of palpable cryptorchidism in children aged <3 years: 10-year experience with 1034 cases.

This study was performed to summarize our clinical experience with testicular descent and fixation through a scrotal stria incision for the treatment of palpable cryptorchidism in children. This study included 1034 children with palpable cryptorchidism from March 2009 to March 2019. A scrotal stria incision was used to perform testicular descent and fixation. Overall, 1020 children successfully underwent surgical testicular descent and fixation through a scrotal stria incision, and 14 patients underwent conversion to inguinal incision surgery. All patients were discharged 1-2 days after the operation. During hospitalization and follow-up, 55 patients developed complications, including 10 patients with testicular retraction, 7 with poor healing of the incision, and 38 with a scrotal hematoma. No patients developed testicular atrophy, an indirect inguinal hernia, or a hydrocoele. Testicular descent and fixation through a scrotal stria incision for the treatment of palpable cryptorchidism in children is safe and feasible in well-selected cases. This method has the advantages of no scarring and a good cosmetic effect.

The Safety and Effectiveness of Laparoscopic versus Open Surgery for Congenital Hypertrophic Pyloric Stenosis in Infants.

BACKGROUND This study aimed to investigate the safety and effectiveness of laparoscopic pyloromyotomy for infants with congenital hypertrophic pyloric stenosis. MATERIAL AND METHODS The clinical data of 233 infants with congenital hypertrophic pyloric stenosis who were treated at our hospital from January 2013 to January 2018 were analyzed retrospectively. The patients were divided into 2 groups: the laparoscopic group (group A, n=126) and the conventional operation group (group B, n=107). RESULTS Laparoscopic surgery was successfully performed in all patients in the laparoscopic group, and none of the surgeries were converted to open surgery. Compared with traditional surgery, laparoscopic surgery has obvious advantages in operation time (29.8±12.9 minutes versus 37.2±17.5 minutes, P=0.012), postoperative feeding time (10.3±2.2 hours versus 15.2±4.1 hours, P=0.035), postoperative hospitalization time (2.8±0.7 days versus 3.5±1.9 days, P=0.013), incision length (0.9±0.2 cm versus 3.3±0.8 cm, P=0.002) and poor wound healing (0 versus 6, P=0.007). No complications, such as bleeding, gastric perforation, duodenal injury, abdominal infection or recurrent vomiting, were observed in the 2 groups. The growth and development (weight and height) of the infants in both groups were normal. CONCLUSIONS Laparoscopic pyloromyotomy has the same safety and effectiveness as the traditional operation and has the advantages of less trauma, faster recovery and cosmetically pleasing incisions.