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1.
NPJ Microgravity ; 10(1): 65, 2024 Jun 06.
Article in English | MEDLINE | ID: mdl-38844548

ABSTRACT

The space exploration from a low earth orbit to a high earth orbit, then to Moon, Mars, and possibly asteroids and moons of other planets is one of the biggest challenges for scientists and engineers for the new millennium. The enabling of in-space cryogenic rocket engines and the Lower-Earth-Orbit (LEO) cryogenic fuel depots for these future manned and robotic space exploration missions begins with the technology development of advanced cryogenic thermal-fluid management systems for the propellant transfer line and storage tank system. One of the key thermal-fluid management operations is the chilldown and filling of the propellant storage tank in space. As a result, highly energy efficient, breakthrough concepts for quenching heat transfer to conserve and minimize the cryogen consumption during chilldown have become the focus of engineering research and development, especially for the deep-space mission to Mars. In this paper, we introduce such thermal transport concepts and demonstrate their feasibilities in space for cryogenic propellant storage tank chilldown and filling in a simulated space microgravity condition on board an aircraft flying a parabolic trajectory. In order to maximize the storage tank chilldown thermal efficiency for the least amount of required cryogen consumption, the breakthrough quenching heat transfer concepts developed include the combination of charge-hold-vent (CHV) and no-vent-hold (NVF). The completed flight experiments successfully demonstrated the feasibility of the concepts and discovered that spray cooling combined with hold and vent is more efficient than the pure spray cooling for storage tank chilldown in microgravity. In microgravity, the data shows that the CHV thermal efficiency can reach 39.5%. The CHV efficiency in microgravity is 6.9% lower than that in terrestrial gravity. We also found that pulsing the spray can increase CHV efficiency by 6.1% in microgravity.

2.
Mol Cell Endocrinol ; 590: 112265, 2024 Sep 01.
Article in English | MEDLINE | ID: mdl-38697385

ABSTRACT

The neuroendocrine system of crustaceans is complex and regulates many processes, such as development, growth, reproduction, osmoregulation, behavior, and metabolism. Once stimulated, crustaceans' neuroendocrine tissues modulate the release of monoamines, ecdysteroids, and neuropeptides that can act as hormones or neurotransmitters. Over a few decades, research has unraveled some mechanisms governing these processes, substantially contributing to understanding crustacean physiology. More aspects of crustacean neuroendocrinology are being comprehended with molecular biology, transcriptome, and genomics analyses. Hence, these studies will also significantly enhance the ability to cultivate decapods, such as crabs and shrimps, used as human food sources. In this review, current knowledge on crustacean endocrinology is updated with new findings about crustacean hormones, focusing mainly on the main neuroendocrine organs and their hormones and the effects of these molecules regulating metabolism, growth, reproduction, and color adaptation. New evidence about vertebrate-type hormones found in crustaceans is included and discussed. Finally, this review may assist in understanding how the emerging chemicals of environmental concern can potentially impair and disrupt crustacean's endocrine functions and their physiology.


Subject(s)
Crustacea , Neurosecretory Systems , Animals , Crustacea/physiology , Crustacea/metabolism , Neuropeptides/metabolism , Neurosecretory Systems/physiology , Neurosecretory Systems/metabolism , Reproduction/physiology
3.
NPJ Precis Oncol ; 8(1): 69, 2024 Mar 11.
Article in English | MEDLINE | ID: mdl-38467830

ABSTRACT

We report a case of Mismatch Repair Deficiency (MMRD) caused by germline homozygous EPCAM deletion leading to tissue-specific loss of MSH2. Through the use of patient-derived cells and organoid technologies, we performed stepwise in vitro differentiation of colonic and brain organoids from reprogrammed EPCAMdel iPSC derived from patient fibroblasts. Differentiation of iPSC to epithelial-colonic organoids exhibited continuous increased EPCAM expression and hypermethylation of the MSH2 promoter. This was associated with loss of MSH2 expression, increased mutational burden, MMRD signatures and MS-indel accumulation, the hallmarks of MMRD. In contrast, maturation into brain organoids and examination of blood and fibroblasts failed to show similar processes, preserving MMR proficiency. The combined use of iPSC, organoid technologies and functional genomics analyses highlights the potential of cutting-edge cellular and molecular analysis techniques to define processes controlling tumorigenesis and uncovers a new paradigm of tissue-specific MMRD, which affects the clinical management of these patients.

5.
bioRxiv ; 2023 Nov 22.
Article in English | MEDLINE | ID: mdl-38045341

ABSTRACT

Here we report the discovery of MED6-189, a new analogue of the kalihinol family of isocyanoterpene (ICT) natural products. MED6-189 is effective against drug-sensitive and -resistant P. falciparum strains blocking both intraerythrocytic asexual replication and sexual differentiation. This compound was also effective against P. knowlesi and P. cynomolgi. In vivo efficacy studies using a humanized mouse model of malaria confirms strong efficacy of the compound in animals with no apparent hemolytic activity or apparent toxicity. Complementary chemical biology, molecular biology, genomics and cell biological analyses revealed that MED6-189 primarily targets the parasite apicoplast and acts by inhibiting lipid biogenesis and cellular trafficking. Genetic analyses in P. falciparum revealed that a mutation in PfSec13, which encodes a component of the parasite secretory machinery, reduced susceptibility to the drug. The high potency of MED6-189 in vitro and in vivo, its broad range of efficacy, excellent therapeutic profile, and unique mode of action make it an excellent addition to the antimalarial drug pipeline.

6.
BMC Genomics ; 24(1): 764, 2023 Dec 11.
Article in English | MEDLINE | ID: mdl-38082257

ABSTRACT

BACKGROUND: Crustacean female sex hormone (CFSH) controls gradually developing adult female-specific morphological features essential for mating and brood care. Specifically, ovigerous hairs are developed during the prepuberty molt cycle of the blue crab Callinectes sapidus that are essential for carrying the eggs until they finish development. Reduced CFSH transcripts by CFSH-dsRNA injections result in fewer and shorter ovigerous hairs than the control. This study aimed to identify the specific genes responsible for ovigerous hair formation using transcriptomic, genomic and expression analyses of the ovigerous setae at three stages: prepuberty at early (OE) and late premolt (OL), and adult (AO) stages. RESULTS: The de novo Trinity assembly on filtered sequence reads produced 96,684 Trinity genes and 124,128 transcripts with an N50 of 1,615 bp. About 27.3% of the assembled Trinity genes are annotated to the public protein sequence databases (i.e., NR, Swiss-Prot, COG, KEGG, and GO databases). The OE vs. OL, OL vs. AO, and OE vs. AO comparisons resulted in 6,547, 7,793, and 7,481 differentially expressed genes, respectively, at a log2-fold difference. Specifically, the genes involved in the Wnt signaling and cell cycle pathways are positively associated with ovigerous hair development. Moreover, the transcripts of ten cuticle protein genes containing chitin-binding domains are most significantly changed by transcriptomic analysis and RT-qPCR assays, which shows a molt-stage specific, down-up-down mode across the OE-OL-AO stages. Furthermore, the expression of the cuticle genes with the chitin-binding domain, Rebers and Riddiford domain (RR)-1 appears at early premolt, followed by RR-2 at late premolt stage. Mapping these 10 cuticle protein sequences to the C. sapidus genome reveals that two scaffolds with a 549.5Kb region and 35 with a 1.19 Mb region harbor 21 RR1 and 20 RR2 cuticle protein genes, respectively. With these findings, a putative mode of CFSH action in decapod crustaceans is proposed. CONCLUSIONS: The present study describes a first step in understanding the mechanism underlying ovigerous hair formation in C. sapidus at the molecular level. Overall, demonstrating the first transcriptome analysis of crustacean ovigerous setae, our results may facilitate future studies into the decapod female reproduction belonging to the suborder Pleocyemata.


Subject(s)
Brachyura , Animals , Female , Proteins/metabolism , Transcriptome , Gene Expression Profiling , Genomics , Chitin/metabolism
7.
Hong Kong Med J ; 29(6): 498-505, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37981743

ABSTRACT

INTRODUCTION: Threatened miscarriage is a common complication of pregnancy. This study aimed to assess psychological morbidity in women with threatened miscarriage, with the goal of identifying early interventions for women at risk of anxiety or depression. METHODS: Women in their first trimester attending an Early Pregnancy Assessment Clinic were recruited between July 2013 and June 2015. They were asked to complete the 12-item General Health Questionnaire (GHQ-12), the Beck Depression Inventory (BDI), Spielberger's State Anxiety Inventory State form (STAI-S), the Fatigue Scale-14 (FS-14), and the Profile of Mood States (POMS) before consultation. They were also asked to rate anxiety levels before and after consultation using a visual analogue scale (VAS). RESULTS: In total, 1390 women completed the study. The mean ± standard deviation of GHQ-12 (bi-modal) and GHQ-12 (Likert) scores were 4.04 ± 3.17 and 15.19 ± 5.30, respectively. Among these women, 48.4% had a GHQ-12 (bi-modal) score ≥4 and 76.7% had a GHQ-12 (Likert) score >12, indicating distress. The mean ± standard deviation of BDI, STAI-S, and FS-14 scores were 9.35 ± 7.19, 53.81 ± 10.95, and 2.40 ± 0.51, respectively. The VAS score significantly decreased after consultation (P<0.001). Compared with women without a history of miscarriage, women with a previous miscarriage had higher GHQ-12, BDI, and POMS scores (except for fatigue-inertia and vigour-activity subscales). A higher bleeding score was strongly positively correlated with GHQ-12 (Likert) score. There were weak correlations between pain score and the GHQ-12 (bi-modal) ≥4, BDI >12, and POMS scores (except for confusion-bewilderment subscale which showed a strong positive correlation). CONCLUSION: Women with threatened miscarriage experience a considerable psychological burden, emphasising the importance of early recognition for timely management.


Subject(s)
Abortion, Spontaneous , Abortion, Threatened , Pregnancy , Female , Humans , Abortion, Spontaneous/epidemiology , Cross-Sectional Studies , Anxiety/epidemiology , Anxiety/psychology , Morbidity
8.
Nat Commun ; 14(1): 6222, 2023 10 06.
Article in English | MEDLINE | ID: mdl-37798294

ABSTRACT

Natural variability in menstrual cycle length, coupled with rapid changes in endometrial gene expression, makes it difficult to accurately define and compare different stages of the endometrial cycle. Here we develop and validate a method for precisely determining endometrial cycle stage based on global gene expression. Our 'molecular staging model' reveals significant and remarkably synchronised daily changes in expression for over 3400 endometrial genes throughout the cycle, with the most dramatic changes occurring during the secretory phase. Our study significantly extends existing data on the endometrial transcriptome, and for the first time enables identification of differentially expressed endometrial genes with increasing age and different ethnicities. It also allows reinterpretation of all endometrial RNA-seq and array data that has been published to date. Our molecular staging model will significantly advance understanding of endometrial-related disorders that affect nearly all women at some stage of their lives, such as heavy menstrual bleeding, endometriosis, adenomyosis, and recurrent implantation failure.


Subject(s)
Endometrium , Uterine Diseases , Female , Humans , Endometrium/metabolism , Menstrual Cycle/genetics , Menstrual Cycle/metabolism , Uterine Diseases/metabolism , Transcriptome , Biopsy
9.
Vaccine ; 2023 Oct 11.
Article in English | MEDLINE | ID: mdl-37833124

ABSTRACT

CatSper is a voltage dependent calcium ion channel present in the principal piece of sperm tail. It plays a crucial role in sperm hyperactivated motility and so in fertilization. Extracellular loops of mouse sperm CatSper were used to develop a vaccine to achieve protection from pregnancy. These loops were inserted at one of the three hypervariable regions of Human Papilloma Virus (HPV) capsid protein (L1). Recombinant vaccines were expressed in E.coli as inclusion body (IB), purified, refolded and assembled into virus-like particles (VLP) in vitro, and adsorbed on alum. Four vaccine candidates were tested in Balb/C mice. All the constructs proved immunogenic, one showed contraceptive efficacy. This recombinant contraceptive vaccine is a non-hormonal intervention and is expected to give long-acting protection from undesired pregnancies.

10.
Hong Kong Med J ; 29(3): 233-239, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37226490

ABSTRACT

INTRODUCTION: Manual vacuum aspiration is increasingly accepted as an alternative to medical or surgical evacuation of the uterus after first-trimester miscarriage. This study aimed to assess the efficacy of ultrasound-guided manual vacuum aspiration (USG-MVA) in the management of first-trimester miscarriage. METHODS: This retrospective analysis included adult women with first-trimester miscarriage who underwent USG-MVA in Hong Kong between July 2015 and February 2021. The primary outcome was the efficacy of USG-MVA in terms of complete evacuation of the uterus, without the need for further medical or surgical intervention. Secondary outcomes included tolerance of the entire procedure, the success rate of karyotyping using chorionic villi, and procedural safety (ie, any clinically significant complications). RESULTS: In total, 331 patients were scheduled to undergo USG-MVA for first-trimester miscarriage or incomplete miscarriage. The procedure was completed in 314 patients and well-tolerated in all of those patients. The complete evacuation rate was 94.6% (297/314), which is similar to the rate (98.1%) achieved by conventional surgical evacuation in a previous randomised controlled trial in our unit. There were no major complications. Samples from 95.2% of patients were suitable for karyotyping, which is considerably higher than the rate of suitable samples (82.9%) obtained via conventional surgical evacuation in our previous randomised controlled trial. CONCLUSION: Ultrasound-guided manual vacuum aspiration is a safe and effective method to manage first-trimester miscarriage. Although it currently is not extensively used in Hong Kong, its broader clinical application could avoid general anaesthesia and shorten hospital stay.


Subject(s)
Abortion, Spontaneous , Pregnancy , Adult , Humans , Female , Pregnancy Trimester, First , Vacuum Curettage/methods , Retrospective Studies , Ultrasonography, Interventional
12.
Hong Kong Med J ; 29(2): 121-131, 2023 04.
Article in English | MEDLINE | ID: mdl-36822598

ABSTRACT

INTRODUCTION: Worldwide, >130 babies have been born from ovarian tissue cryopreservation (OTC) and ovarian tissue transplantation (OTT). Ovarian tissue cryopreservation can improve quality of life among young female cancer survivors. Here, we assessed the feasibility of OTC and subsequent OTT in Hong Kong via xenografts in nude mice. METHODS: This pilot study was conducted in a university-affiliated tertiary hospital. Fifty-two ovarian tissues were collected from 12 patients aged 29 to 41 years during ovarian surgery, then engrafted into 34 nude mice. The efficacies of slow freezing and vitrification were directly compared. In Phase I, non-ovariectomised nude mice underwent ovarian tissue engraftment. In Phase II, ovariectomised nude mice underwent ovarian tissue engraftment, followed by gonadotrophin administration to promote folliculogenesis. Ovarian tissue viability was assessed by gross anatomical, histological, and immunohistochemical examinations before and after OTC. Follicular density and morphological integrity were also assessed. RESULTS: After OTC and OTT, grafted ovarian tissues remained viable in nude mice. Primordial follicles were observed in thawed and grafted ovarian tissues, indicating that the cryopreservation and transplantation protocols were both effective. The results were unaffected by gonadotrophin stimulation. CONCLUSION: This study demonstrated the feasibility of OTC in Hong Kong as well as primordial follicle viability after OTC and OTT in nude mice. Ovarian tissue cryopreservation is ideal for patients who cannot undergo the ovarian stimulation necessary for oocyte or embryo freezing as well as prepubertal girls (all ineligible for oocyte freezing). Our findings support the clinical implementation of OTC and subsequent OTT in Hong Kong.


Subject(s)
Fertility Preservation , Animals , Mice , Female , Humans , Mice, Nude , Fertility Preservation/methods , Hong Kong , Pilot Projects , Quality of Life , Cryopreservation/methods
13.
J Visc Surg ; 160(1): 12-18, 2023 02.
Article in English | MEDLINE | ID: mdl-35459632

ABSTRACT

INTRODUCTION: The standard of care for intraperitoneal injury in hemodynamically stable patients after blunt abdominal trauma has been replaced by non-operative management (NOM). However, selective NOM, depending on the situation, seems necessary in determining the treatment plan. In this study, we attempted to identify risk factors for surgical or angiographic intervention (SAI) in hemodynamically stable blunt abdominal trauma patients. METHODS: This retrospective study which included adult patients who were brought to a regional trauma center was conducted from March 2015 to October 2019. We evaluated the characteristics of blunt abdominal trauma patients and analyzed factors that were related to the requirement of SAI in these patients. Patients were divided into SAI and conservative management (CM) groups. RESULTS: We reviewed 1,176 patients, and after exclusions, of whom 248 blunt abdominal trauma and free fluid observed on CT were identified. The mean pulse rate was higher in the SAI than in the CM (P=0.025). Laboratory findings showed that lactate and delta neutrophil index (DNI) levels were higher in the SAI than in the CM (P=0.002 and 0.026 respectively). Additionally, the mean free fluid size in the SAI (85.69mm) was significantly larger than that in the CM (68.12mm; P=0.001), and blush was more frequently observed in the SAI (P<0.001). In multivariate analysis, only blush was an independent prognostic factor for SAI (OR 11.7, 95% CI, 5.1-30.8, P<0.001). CONCLUSION: In hemodynamically stable patients with blunt abdominal trauma, blush but also high lactate and DNI are associated with the requirement of interventional radiology and/or surgery.


Subject(s)
Abdominal Injuries , Wounds, Nonpenetrating , Adult , Humans , Abdominal Injuries/diagnostic imaging , Abdominal Injuries/surgery , Retrospective Studies , Risk Factors , Trauma Centers , Wounds, Nonpenetrating/diagnostic imaging , Wounds, Nonpenetrating/surgery
14.
Pediatr Res ; 93(6): 1528-1538, 2023 05.
Article in English | MEDLINE | ID: mdl-36030318

ABSTRACT

BACKGROUND: Low levels of insulin-like growth factor-1 (IGF-1) protein in preterm human infants are associated with bronchopulmonary dysplasia (BPD). We used our preterm lamb model of BPD to determine (1) dosage of recombinant human (rh) IGF-1 bound to binding protein-3 (IGFBP-3) to reach infant physiologic plasma levels; and (2) whether repletion of plasma IGF-1 improves pulmonary and cardiovascular outcomes. METHODS: Group 1: normal, unventilated lambs from 128 days gestation through postnatal age 5 months defined normal plasma levels of IGF-1. Group 2: continuous infusion of rhIGF-1/rhIGFBP-3 (0.5, 1.5, or 4.5 mg/kg/day; n = 2) for 3 days in mechanically ventilated (MV) preterm lambs determined that 1.5 mg/kg/day dosage attained physiologic plasma IGF-1 concentration of ~125 ng/mL, which was infused in four more MV preterm lambs. RESULTS: Group 1: plasma IGF-1 protein increased from ~75 ng/mL at 128 days gestation to ~220 ng/L at 5 months. Group 2: pilot study of the optimal dosage (1.5 mg/kg/day rhIGF-1/rhIGFBP-3) in six MV preterm lambs significantly improved some pulmonary and cardiovascular outcomes (p < 0.1) compared to six MV preterm controls. RhIGF-1/rhIGFBP-3 was not toxic to the liver, kidneys, or lungs. CONCLUSIONS: Three days of continuous iv infusion of rhIGF-1/rhIGFBP-3 at 1.5 mg/kg/day improved some pulmonary and cardiovascular outcomes without toxicity. IMPACT: Preterm birth is associated with rapid decreases in serum or plasma IGF-1 protein level. This decline adversely impacts the growth and development of the lung and cardiovascular system. For this pilot study, continuous infusion of optimal dosage of rhIGF-1/rhIGFBP-3 (1.5 mg/kg/day) to maintain physiologic plasma IGF-1 level of ~125 ng/mL during mechanical ventilation for 3 days statistically improved some structural and biochemical outcomes related to the alveolar formation that would favor improved gas exchange compared to vehicle-control. We conclude that 3 days of continuous iv infusion of rhIGF-1/rhIGFBP-3 improved some physiological, morphological, and biochemical outcomes, without toxicity, in mechanically ventilated preterm lambs.


Subject(s)
Bronchopulmonary Dysplasia , Premature Birth , Infant , Female , Humans , Animals , Infant, Newborn , Sheep , Insulin-Like Growth Factor I/metabolism , Bronchopulmonary Dysplasia/drug therapy , Pilot Projects , Infant, Premature , Recombinant Proteins/metabolism , Insulin-Like Growth Factor Binding Protein 3 , Sheep, Domestic
15.
Int J Oral Maxillofac Surg ; 52(9): 956-963, 2023 Sep.
Article in English | MEDLINE | ID: mdl-36460573

ABSTRACT

Segmental mandibular advancement (SMA) consists of a combination of bilateral sagittal split osteotomy, anterior subapical osteotomy with extraction of the first premolars, and genioplasty, to allow an extended advancement of the mandible for the improvement of tongue base obstruction in moderate-to-severe obstructive sleep apnoea (OSA) and to minimize any unfavourable aesthetic change due to the large jaw advancement. The aim of this pilot study was to evaluate the surgical outcomes and complications following SMA in OSA patients. Twelve patients (nine male, three female) underwent SMA as part or whole of their skeletal advancement procedure for OSA. The apnoea-hypopnoea index (AHI) improved from a mean± standard deviation 42.4 ± 22.0/hour preoperatively to 9.0 ± 17.4/hour at 1 year postoperative. Surgical success (50% reduction in AHI) was achieved in 11 of the 12 patients (91.7%) at 1 year postoperative, while seven patients (58.3%) attained surgical cure (AHI<5/hour). The lowest oxygen saturation (LSAT) increased from a mean 73.3% preoperatively to 78.7% at 1 year postoperative. The airway volume increased from a mean 2.4 ± 1.7 cm3 at baseline to 6.7 ± 3.5 cm3 at 1 year postoperative (P < 0.001). No major complication occurred. This pilot study showed that SMA appears to be safe and effective as part or whole of the skeletal advancement surgery for moderate-to-severe OSA.


Subject(s)
Mandibular Advancement , Sleep Apnea, Obstructive , Humans , Male , Female , Mandibular Advancement/methods , Pilot Projects , Treatment Outcome , Esthetics, Dental , Sleep Apnea, Obstructive/surgery , Osteotomy, Sagittal Split Ramus/methods
16.
Gen Comp Endocrinol ; 330: 114128, 2023 01 01.
Article in English | MEDLINE | ID: mdl-36152768

ABSTRACT

Eyestalk-derived neuropeptides, primarily the crustacean hyperglycemic hormone (CHH) neuropeptide family, regulate vitellogenesis in decapod crustaceans. The red deep-sea crab, Chaceon quinquedens, a cold-water species inhabiting depths between 200 and 1800 m, has supported a small fishery, mainly harvesting adult males in the eastern US for over 40 years. This study aimed to understand the role of eyestalk-neuropeptides in vitellogenesis in C. quinquedens with an extended intermolt stage. Chromatography shows two CHH and one MIH peak in the sinus gland, with a CHH2 peak area four times larger than CHH1. The cDNA sequence of MIH and CHH of C. quinquedens is isolated from the eyestalk ganglia, and the qPCR assay shows MIH is significantly higher only at ovarian stages 3 than 4 and 5. However, MIH transcript and its neuropeptides do differ between stages 1 and 3. While CHH transcripts remain constant, its neuropeptide levels are higher at stages 3 than 1. Additionally, transcriptomic analysis of the de novo eyestalk ganglia assembly at ovarian stages 1 and 3 found 28 eyestalk neuropeptides. A GIH/VIH or GSH/VSH belonging to the CHH family is absent in the transcriptome. Transcripts per million (TPM) values of ten neuropeptides increase by 1.3 to 2.0-fold at stage 3 compared to stage 1: twofold for Bursicon α, followed by CHH, AKH/corazonin-like, Pyrokinin, CCAP, Glycoprotein B, PDH1, and IDLSRF-like peptide, and 1.3-fold of allatostatin A and short NP-F. WXXXRamide, the only downregulated neuropeptide, decreases TPM by âˆ¼ 2-fold at stage 3, compared to stage 1. Interestingly, neuroparsin with the highest TPM values remains the same in stages 1 and 3. The mandibular organ-inhibiting hormone is not found in de novo assembly. We report that CHH, MIH, and eight other neuropeptides may play a role in vitellogenesis in this species.


Subject(s)
Brachyura , Invertebrate Hormones , Neuropeptides , Animals , Male , Female , Brachyura/genetics , Invertebrate Hormones/genetics , Arthropod Proteins/genetics , Neuropeptides/genetics , Neuropeptides/chemistry , Ganglia , DNA, Complementary , Transcriptome
17.
J Laryngol Otol ; 137(6): 643-650, 2023 Jun.
Article in English | MEDLINE | ID: mdl-35968691

ABSTRACT

OBJECTIVE: This study aimed to analyse surgical outcomes of paediatric patients with congenital cholesteatoma according to age. METHOD: This was a retrospective study reviewing the records of 186 children (136 boys and 50 girls) from August 1993 to January 2016. Patients were divided into three age groups (equal to or less than 3 years, over 3 and less than 7 years, and 7 to 15 years). RESULTS: There were significant differences in chief complaints, location of cholesteatoma in the middle ear, computed tomography findings, operation methods, ossicular erosion and type of cholesteatoma sac among the three groups. In addition, older age, open type cholesteatoma, ossicular erosion and mastoid invasion of cholesteatoma increased the recurrence rate after surgery. However, despite higher pre-operative air-bone gap in older children, hearing can be improved enough after proper surgery with ossicular reconstruction. CONCLUSION: Delayed detection of paediatric cholesteatoma can lead to extensive disease and the need for an aggressive operation, which can result in worse hearing outcomes and an increased recurrence risk.


Subject(s)
Cholesteatoma, Middle Ear , Cholesteatoma , Male , Female , Humans , Child , Child, Preschool , Cholesteatoma, Middle Ear/diagnostic imaging , Cholesteatoma, Middle Ear/surgery , Retrospective Studies , Treatment Outcome , Cholesteatoma/surgery , Ear, Middle , Mastoid/diagnostic imaging , Mastoid/surgery
18.
Nature ; 609(7926): 269-275, 2022 09.
Article in English | MEDLINE | ID: mdl-36071190

ABSTRACT

Nuclear fusion is one of the most attractive alternatives to carbon-dependent energy sources1. Harnessing energy from nuclear fusion in a large reactor scale, however, still presents many scientific challenges despite the many years of research and steady advances in magnetic confinement approaches. State-of-the-art magnetic fusion devices cannot yet achieve a sustainable fusion performance, which requires a high temperature above 100 million kelvin and sufficient control of instabilities to ensure steady-state operation on the order of tens of seconds2,3. Here we report experiments at the Korea Superconducting Tokamak Advanced Research4 device producing a plasma fusion regime that satisfies most of the above requirements: thanks to abundant fast ions stabilizing the core plasma turbulence, we generate plasmas at a temperature of 100 million kelvin lasting up to 20 seconds without plasma edge instabilities or impurity accumulation. A low plasma density combined with a moderate input power for operation is key to establishing this regime by preserving a high fraction of fast ions. This regime is rarely subject to disruption and can be sustained reliably even without a sophisticated control, and thus represents a promising path towards commercial fusion reactors.

19.
Front Endocrinol (Lausanne) ; 13: 962576, 2022.
Article in English | MEDLINE | ID: mdl-35957817

ABSTRACT

17ß-estradiol (E2) has been proved to control reproduction, sexual differentiation, and the development of the secondary sexual characteristics of vertebrate females. In decapod crustacean species, crustacean female sex hormone (CFSH), a protein hormone, is required for developing adult-specific ovigerous setae for embryo brooding and gonophores for mating at the blue crab Callinectes sapidus puberty molting. However, it is unclear that whether the mode of CFSH action involves a vertebrate-type sex steroid hormone in crustaceans. To this end, E2 levels were first measured using a competitive ELISA in the hemolymph and the potential CFSH target tissues from both prepuberty and adult females; the presence of E2 was further confirmed with a liquid chromatography tandem mass spectrometry method. Then, the cDNAs of the following genes known to be associated with vertebrate steroidogenic pathways were isolated: StAR-related lipid transfer protein 3 (StAR3); 3ß-hydroxysteroid dehydrogenase (3ßHSD); two isoforms of 17ß-hydroxysteroid dehydrogenase 8 (17ßHSD8); and, estradiol-related receptor (ERR). RT-PCR analysis revealed that these genes were widely distributed in the eyestalk ganglia, hepatopancreas, brain, ovary, spermathecae, ovigerous and plumose setae tissues of adult females. The 17ßHSD8 transcripts were localized in the follicle cells, the periphery of the nuclear membrane of primary oocytes, and yolk granules of the vitellogenic oocytes using in situ hybridization, and the corresponding protein was detected in the follicle cells and ooplasm of primary oocytes using immunohistochemistry. Furthermore, the adult females injected with CFSH-dsRNA (n = 30 times) had E2 and StAR3 transcripts levels lower in the ovigerous and plumose setae, spermathecae than controls. These results suggested that the mode of CFSH action in C. sapidus might involve E2 in these adult-female-specific tissues.


Subject(s)
Brachyura , Animals , Brachyura/genetics , Estradiol , Female , Gonadal Steroid Hormones/metabolism , Hepatopancreas/metabolism , Sexual Maturation
20.
NPJ Microgravity ; 8(1): 33, 2022 Aug 09.
Article in English | MEDLINE | ID: mdl-35945252

ABSTRACT

The enabling of in-space cryogenic engines and cryogenic fuel depots for future manned and robotic space exploration missions begins with technology development of advanced cryogenic fluid management systems upstream in the propellant feed system. Before single-phase liquid can flow to the engine or customer spacecraft receiver tank, the connecting transfer line must first be chilled down to cryogenic temperatures. The most direct and simplest method to quench the line is to use the cold propellant itself. When a cryogenic fluid is introduced into a warm transfer system, two-phase flow quenching ensues. While boiling is well known to be a highly efficient mode of heat transfer, previous work has shown this efficiency is lowered in reduced gravity. Due to the projected cost of launching and storing cryogens in space, it is desired to perform this chilldown process using the least amount of propellant possible, especially given the desire for reusable systems and thus multiple transfers. This paper presents an assessment of two revolutionary new performance enhancements that reduce the amount of propellant consumed during chilldown while in a microgravity environment. Twenty-eight cryogenic transfer line chilldown experiments were performed onboard four parabolic flights to examine the independent as well as combined effect of using low thermally conductive coatings and pulse flow on the chilldown process. Across a range of Reynolds numbers, results show the combination significantly enhances performance in microgravity, with a reduction in consumed mass up to 75% relative to continuous flow for a bare transfer line.

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