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Why does speleothem δ 18 O differ from groundwater δ 18 O in the late Pleistocene? In...
Jie Li
Lijun Tian

Jie Li

and 3 more

May 27, 2022
Both δ 18O in groundwater and speleothem are inherited from precipitation δ 18O, however, stalagmite δ 18O and groundwater δ 18O do not simultaneously agree with each other in the monsoon regions, especially in the late Pleistocene. The reason remains unclear due to the complex stable isotope systematics in the monsoon affected regions with their controlling factors as well as the possible different recharge dynamics of groundwater and drip water. In this study, we have collected 539 daily precipitation samples throughout 2015 from seven monitoring stations in Beijing, in the northern margin of the East Asian summer monsoon region. Stable isotopes (δ 18O and δ 2H) of these precipitation samples are investigated for the controlling factors of precipitation isotopes, e.g., moisture source, temperature (T), and precipitation amount (P) effects. The δ 18O values in the precipitation decrease from the south to the northwest, which is controlled by the monsoon from the south and continental moisture from the northwest. Consistently, the precipitation exhibits an apparent seasonal variation in δ 18O values. The P effect is significant during the monsoon season, especially when the precipitation events are greater than 5 mm and single moisture source is considered. In contrast, the T effect is significant, with a gradient of 0.4‰ per °C during the non-monsoon season. A Rayleigh distillation model indicates that the moisture source and residual vapor fraction are the two most important factors controlling the δ 18O precipitation patterns in a monsoon region, independent of temperature. Isotopes in groundwater in the late Pleistocene exhibit a significant T effect, implying that the monsoon might not reach Beijing when the groundwater was formed at that time. Furthermore, we highlighted the different recharge mechanisms of groundwater and drip water: lateral flow and direct vertical infiltration make diverse contributions of non-monsoon precipitations to the groundwater and drip water respectively, resulting in that speleothem δ 18O differ from groundwater δ 18O in the late Pleistocene.
Numerical study on stability of composite cutter bar milling system in rotating coord...
Yuhuan Zhang
Yongsheng Ren

Yuhuan Zhang

and 2 more

May 27, 2022
This paper studies chatter stability of composite cutter bar milling system in rotating coordinate frame. Based on the structural dynamic equation and regenerative milling force model of composite cutter bar in rotating coordinate frame, the continuous distributed chatter analysis model of composite cutter bar milling system is established. The stability of milling system with a rotary symmetric dynamic cutter bar is predicted by using the semi-discrete time domain method. Influences including internal damping, external damping, symmetrical and asymmetric laminates on the stability of milling system are analyzed, and the results obtained in rotating and fixed coordinate frame are compared. It is shown that the results are consistent for symmetrical cutter bar either in the rotating coordinate frame or in the fixed coordinate frame. A new chatter instability zone appears at high rotating speeds due to material internal damping of the rotating composite cutter bar.
Resolution of severe cardiomyopathy after catheter ablation of an anteroseptal access...
Omar J. Baqal
Vatsal M. Ladia

Omar J. Baqal

and 2 more

May 27, 2022
Background: In patients with non-sustained tachyarrhythmias, left ventricular (LV) systolic dysfunction is uncommon. The role of catheter ablation (CA) in asymptomatic patients with tachyarrhythmia remains unclear. Case presentation: We report a 20-year-old patient without sustained tachyarrhythmia with a left ventricular ejection fraction of 20% who underwent radiofrequency catheter ablation (RFCA) of anteroseptal accessory pathway. She achieved normalization of left ventricular systolic function noted on echocardiography performed at four weeks post-ablation. Conclusions: Our case highlights significant improvement in LV systolic function after catheter ablation of an “asymptomatic” ventricular preexcitation. Current guidelines do not endorse ablating asymptomatic patients, but careful follow up with serial echocardiograms might be warranted. Prophylactic ablation of those patients with clear evidence of LV dyssynchrony or wide left bundle branch pattern and persistent preexcitation is worth further consideration.
Inadvertent lead malposition in the left heart during implantation of cardiac electri...
Lorenzo Spighi
Francesco Notaristefano

Lorenzo Spighi

and 10 more

May 27, 2022
Introduction. The inadvertent lead malposition in the left heart chambers (ILMLH) is an under-recognized event which may complicate implantation of cardiac electronic devices (CIEDs). Methods and Results. We investigated the clinical conditions associated with ILMLH and the treatment strategies in these patients. We made a systematic review of literature and identified 132 studies which reported 157 patients with ILMLH. Mean age of patients was 68 years and 83 were women. ILMLH was diagnosed, on average, 365 days after CIEDs implantation. Coexisting conditions were patent foramen ovale in 29% of patients, arterial puncture in 24%, perforation of the interatrial septum in 20%, atrial septal defect in 16% and perforation of the interventricular septum in 4%. At the time of diagnosis of ILMLH, 46% of patients were asymptomatic, 31% had acute TIA or stroke and 15% had overt heart failure. Overall, 14% of patients were receiving anticoagulants at the time of diagnosis of ILMLH. After diagnosis of ILMLH, percutaneous or surgical lead extraction was carried out in 93 patients (59%), whereas 43 (27%) received anticoagulation. During a mean 9-month follow-up after diagnosis of ILMLH, 4 patients experienced TIA or stroke (3 on oral anticoagulant therapy and 1 after percutaneous lead extraction). Conclusion. ILMLH is a rare complication which is usually diagnosed about one year after CIEDs implantation. An early diagnosis of ILMLH is important. Lead extraction is a safe and effective alternative to anticoagulants.
A case report of a Brain herniation secondary to cryptococcal meningitis with elevate...
Nehemias MD Guevara
Abdulrasheed Akande

Nehemias Guevara

and 4 more

May 27, 2022
Cryptococcal meningitis is a major opportunistic infection in individuals with HIV. 36-year-old male with a past medical history of AIDSpresented with altered mental status, lumbar puncture performed showed elevated CSF opening pressure of 29 cmH2O and positive CSF and serum cryptococcal antigen, developed seizure, and posterior brain herniation.
Simultaneous infection of CIED and newly implanted leadless cardiac pacemaker
Mengwei Wu
Hao Su

Mengwei Wu

and 1 more

May 27, 2022
CIED infection is a serious complication and remains the commonest indication for TLE.The patient exist two problems: bilateral venous access infection and pacing dependence. LP provide safe and effective pacing options for patients with device-related infections.
Pulmonary vasodilator therapy in preterm children with bronchopulmonary dysplasia; a...
Ida Jeremiasen
Karin Tran-Lundmark

Ida Jeremiasen

and 3 more

May 27, 2022
Objectives: This study aimed to map prescription patterns of pulmonary vasodilator therapy in children with bronchopulmonary dysplasia (BPD). Working hypothesis: Pulmonary vasodilator drug therapy is used in children born preterm suffering from BPD-associated pulmonary hypertension, but patient selection, extent of diagnostics with catheterization and co-morbidities are largely unknown. Study design: A descriptive national registry-based study. Patient selection and methodology: All children below seven years of age who had been prescribed a pulmonary vasodilator during a ten-year period, 2007-2017, born preterm (gestational age, GA <37 weeks) and classified as BPD, were included. Information on prescriptions was retrieved from the Swedish Prescribed Drug Register and information on patient characteristics and comorbidities was retrieved by linkage to national registers held by the National Board of Health and Welfare. Results: In total, 74 children were included, 54 (73%) born at GA 22-27 and 20 (27%) at GA 28-36. Single therapy was most common, N=64 (86.5%), and sildenafil was most frequently prescribed, N=69 (93%). Bosentan, iloprost, macitentan and/or treprostinil were mainly used for combination therapies, N=10 (13.5%). Patent ductus arteriosus (PDA) or atrial septal defect (ASD) was present in N=29 (39%) and N=25 (34%) children respectively, and N=20 (69%) versus N=3 (12%) underwent closure. Cardiac catheterization was performed in N=19 (26%) patients. Median duration of therapy was 4.4 (0.5-14.1, 95% percentiles) months. Total mortality was N=7 (9%). Conclusions: Preterm children with BPD are prescribed pulmonary vasodilators, often without prior catheterization and sildenafil was most common. Diagnostic tools, effects, and drug safety needs further evaluation.
Right Ventriculography Improves the Accuracy of Micra TM Leadless Pacemaker Implantat...
Baopeng Tang
Yao-Dong Li

Baopeng Tang

and 9 more

May 27, 2022
Background: Implanting leadless pacemakers in the right ventricular (RV) apex is prone to causing pericardial tamponade and myocardial perforation. Objective: To investigate the feasibility and safety of right ventriculography-guided implantation of Micra TM leadless pacemaker (Micra) in the RV mid-septum. Methods: 108 consecutive patients who underwent Micra implantation intended in the mid-septum were enrolled and randomized (3:1) into the radiography group (n=81) with assistance of right ventriculography to illustrate the RV septum and the non-radiography group (n=27). All subjects underwent a postoperative computed tomography (CT) scan to determine the Micra location. The Micra location assessed by CT image was compared between the two groups to confirm the accuracy of the intended pacing site. The duration of the procedure, X-ray exposure dose and time were also compared between the two groups. Results: Reconstructed CT 3-D cardiac imaging found the Micra location in the intended mid-septum in 13 patients (48.1%, 13/27) in the non-radiography group and 76 patients (93.8%, 76/81) in the radiography group ( P< 0.0001 between two groups). There was no significant difference in procedure interval between the two groups while the X-ray exposure (564.86±112.44 vs. 825.85±156.12mGy, P < 0.0001), X-ray exposure time (7.79±1.43vs. 12.03±2.86 min, P < 0.0001) and the number of fluoroscopy re-positioning (2.79±1.03, vs. 6.41±1.82, P<0.0001) were significantly less in the radiography group than in the non-radiography group. No implantation-related complications were observed in both groups. Conclusion Right ventriculography increases the accuracy of Micra TM pacemaker implantation in the mid-septum and reduces X-ray exposure.
Reynold's equation in stochastic form for curved circular and rough porous flat plate...
Salma A
Hanumagowda  B N

Salma A

and 2 more

May 27, 2022
A theoretical analysis of curved circular and rough porous flat plates is studied for the case of conducting couple stress fluid accounting for viscosity variation and MHD. By using Stochastic Reynold's boundary conditions, the equation for pressure distribution is derived. The results reveal that viscosity variation, couple stress, roughness, MHD increases the load carrying capacities and squeezing time while the existence of a porous region decreases the above characteristics.
Room Temperature Fabrication of Oriented Zr-MOF Membrane with Superior Gas Selectivit...
Jiahui Yan
Taotao Ji

Jiahui Yan

and 5 more

May 26, 2022
Rational structural design and engineering of MOF membranes is promising for energy-efficient separation. Preferred orientation manipulation delegates an effective approach to improve their separation performance, while room-temperature (RT) synthetic protocol is beneficial to foster their industrial batch production. Nevertheless, it remains challenging to fabricate highly oriented MOF membranes at RT; simultaneously, the density of defective sites in the framework, which is assumed to exert significant influence on the separation performance relying on high affinity-interactions between guest molecules and coordinatively-unsaturated open metal sites, should be deliberately tailored. In this study, we achieve RT synthesis of highly (111)-oriented UiO-66 membrane exhibiting high defect density in the framework through employing Zr6O4(OH)4(OAc)12 clusters as zirconium source. Prepared membrane manifests an ideal CO2/N2 selectivity of 46.2, which represents the highest value among pure MOF membranes tested in comparable operating conditions. This protocol is expected be expanded for facile and mild preparation of state-of-the-art MOF membranes.
Potential health risks of mRNA-based vaccine therapy: a hypothesis
Karina Acevedo-Whitehouse

Karina Acevedo-Whitehouse

and 1 more

May 27, 2022
Therapeutic applications of synthetic mRNA were proposed more than 30 years ago, and are currently the basis of one of the vaccine platforms used at a massive scale as part of the public health strategy to get COVID-19 under control. To date, there are no published studies on the biodistribution, cellular uptake, endosomal escape, translation rates, functional half-life and inactivation kinetics of synthetic mRNA, rates and duration of vaccine-induced antigen expression in different cell types. Furthermore, despite the assumption that there is no possibility of genomic integration of therapeutic synthetic mRNA, only one recent study has examined interactions between vaccine mRNA and the genome of transfected cells, and reported that an endogenous retrotransposon, LINE-1 is unsilenced following mRNA entry to the cell, leading to reverse transcription of full length vaccine mRNA sequences, and nuclear entry. This finding should be a major safety concern, given the possibility of synthetic mRNA-driven epigenetic and genomic modifications arising. We propose that in susceptible individuals, cytosolic clearance of nucleotide modified synthetic (nms-mRNAs) is impeded. Sustained presence of nms-mRNA in the cytoplasm deregulates and activates endogenous transposable elements (TEs), causing some of the mRNA copies to be reverse transcribed. The cytosolic accumulation of the nms-mRNA and the reverse transcribed cDNA molecules activates RNA and DNA sensory pathways. Their concurrent activation initiates a synchronized innate response against non-self nucleic acids, prompting type-I interferon and pro-inflammatory cytokine production which if unregulated, leads to autoinflammatory and autoimmune conditions, while activated TEs increase the risk of insertional mutagenesis of the reverse transcribed molecules, which can disrupt coding regions, enhance the risk of mutations in tumour suppressor genes, and lead to sustained DNA damage. Susceptible individuals would then expectedly have an increased risk of DNA damage, chronic autoinflammation, autoimmunity and cancer. In light of the current mass administration of nms-mRNA vaccines, it is essential and urgent to fully understand the intracellular cascades initiated by cellular uptake of synthetic mRNA and the consequences of these molecular events.
Effects of food plants on life-history traits of the newly invasive fall armyworm Spo...
Li-Li Huang
Fangsen Xue

Li-Li Huang

and 5 more

May 26, 2022
The fall armyworm (FAW) Spodoptera frugiperda has invaded Jiangxi Province, Southeast China for the past three years. Although the FAW displays a very wide host range, one of its main host plants in Jiangxi Province is still field corn. This study systematically investigated the effects of food plants (corn, peanut, soybean and sugarcane) on life-history traits of FAW and tested the leaf contents of the total flavonoids, reducing sugars, sucrose and C/N ratio. We found that the FAW fed on corn leaves showed significantly shorter larval and pupal development times, larger body weight, higher growth rate, lower weight loss, smaller SSD, shorter preoviposition period and higher fecundity than those fed on peanut, soybean and sugarcane leaves. The pupal development stage was significantly longer in males than females, showing a protogyny phenomenon. Food plants changed the relationships between larval development time and pupal weight and between fecundity and longevity. The corn leaves showed significantly higher contents of reducing sugars and sucrose, lower content of the total flavonoids, and a moderate C/N ratio, suggesting that the corn leaf tissues are more nutritive. These findings may help us to understand why the FAW mainly infests corn plants and may be critical for the development of strategies to predict infestation levels.
Asociación entre síntomas inflamatorios y síntomas depresivos en la población mexican...
Alejandro Mosiño
cesarluh

Alejandro Mosiño

and 1 more

November 09, 2022
Recientemente, diversos estudios clínico-experimentales han encontrado que los pacientes con depresión presentan los componentes característicos de una inflamación. Además, se ha sugerido que la asociación entre inflamación y depresión podría ser bidireccional. Esto se debe a que los comportamientos resultantes de un episodio depresivo tienen el potencial de actuar como vías mediadoras que conducen a una mayor inflamación.  En este trabajo se usan datos de la Encuesta Nacional de Salud y Nutrición 2018 de México para estudiar esta asociación en adultos mayores a 20 años. Utilizando modelos econométricos, se encuentra evidencia estadística de que la inflamación y la depresión están asociados positivamente. Además, se encuentra que los síntomas de depresión están positivamente asociados con la edad, que es más prevalente en mujeres que en hombres y que los habitantes de la zona centro de México son más propensos a sufrir de depresión significativa que los habitantes del resto del país y, específicamente, a los de la Ciudad de México, al igual que los habitantes de zonas rurales. Los resultados aquí obtenidos no solo tienen implicaciones para el tratamiento de la depresión, sino que proporcionan una herramienta para la toma de decisiones en el sector salud.Palabras clave: Depresión; Inflamación; ENSANUT; Modelos Probabilísticos
Estimating resistance surface on multilayers landscapes using gradient forest and all...
Mathieu Vanhove
Sophie Launey

Mathieu Vanhove

and 1 more

May 26, 2022
Understanding landscape connectivity has become a global priority for mitigating the impact of landscape fragmentation on biodiversity. Link-based methods traditionally rely on relating pairwise genetic distance between individuals or demes to their landscape distance (e.g., geographic distance, cost distance). In this study, we present an alternative to conventional statistical approaches to refine cost surfaces by adapting the Gradient Forest (GF) approach to produce a resistance surface based on multiple environmental variables. Used in community ecology, Gradient Forest is an extension of random forest (RF), and has been implemented in genomic studies to model species genetic offset under future climatic scenarios. By design, this adapted method, resGF, has the ability to handle multiple environmental predictors and is not subjected to traditional assumptions of linear models such as independence, normality and linearity. Using genetic simulations, our RF-based approach was compared to other published methods using univariate and multivariate scenarios. Additionally, two worked examples are provided using two previously published datasets. This machine learning algorithm has the potential improve our understanding of landscape connectivity and can inform long-term biodiversity conservation strategies.
Central Nervous System Involvement in Burkitt Lymphoma: A Case Report and Review of L...
Erik Zapata
Andrés Felipe Linares

Erik Zapata

and 3 more

May 26, 2022
Central nervous system involvement in Burkitt lymphoma is a frequent complication, affecting less than 10% of patients with the endemic form, 10%–20% with the non-endemic form, and 20%–30% with the immunodeficiency-associated form. Here we discuss the distinct clinical features, diagnostic approach and chemotherapeutic treatment of three cases in our institution.
Intraspecific variation in growth response to drought stress across geographic locati...
Catherine Kiwuka
Jan Vos

Catherine Kiwuka

and 6 more

May 26, 2022
Uganda lies within the drier end of the natural distribution range of Coffea canephora and contains unexplored genetic material that could be drought-adapted and useful for developing climate-resilient varieties. Using experimental treatments, (i) ample and (ii) restricted-water, response of 148 genotypes were studied comprising wild, feral and cultivated C. canephora. Biomass allocation, standing leaf area and leaf area growth data were collected. Linear mixed effect models and PCA were used to analyse effect of drought on genotypes from different: (i) cultivation status, (ii) genetic groups and (iii) locations. We assessed the relationship between drought tolerance for relative growth rate in leaf area (RGRA), total number of leaves (TNL), total leaf area (TL) and total leaf dry weight (TLDW) of genotypes at final harvest. Restricted-water reduced RGRA across genetic groups (3.2 – 32.5%) and locations (7.1 – 36.7%) but not cultivation status. For TNL, TL and TLDW, genotypes that performed well in ample-water performed worse under restricted-water, indicating growth-tolerance trade-off. Drought tolerance in RGRA and TNL were negatively correlated with wetness index suggesting some degree of adaptation to local climate. Findings indicate a growth-tolerance trade-off within this tropical tree species and drought tolerance of Uganda’s C. canephora is somewhat associated with local climate.
Brassica campestris ssp . chinensis HY5 regulates hypocotyl elongation by binding the...
Yiran Li
Ying He

Yiran Li

and 4 more

May 26, 2022
Abstract Light is a necessary environmental factor for plant growth and development. HY5 (ELONGATED HYPOCOTYL 5), regarded as a crucial transcriptional factor for regulating hypocotyl, was clearly in Arabidopsis thaliana, but its regulatory mechanism in non-heading Chinese cabbage (NHCC) has not been understood. In this study, we used BcHY5 as a bait to screen two BcB-box (BBX) proteins, BcBBX21, and BcBBX25, and applied multiple genetic and biochemical approaches to identify the roles of BcHY5 and two B-BBX proteins. Overexpression of the two BBX proteins in Arabidopsis was used to investigate their functions. BcHY5 can bind the G-box of pro BcMYBH and inhibit BcMYBH transcription. BcHY5 can form a complex with BcBBX21, which promotes BcHY5’s regulation of BcMYBH and increases the transcription inhibition of BcMYBH, resulting in the shorter hypocotyl. BcBBX25 can interact with BcHY5 to release the inhibition of BcMYBH by BcHY5 , allowing the hypocotyl to return to normal. The C-terminal exchange confirmed that the interaction between BcBBXs and BcHY5 was determined by the two B-box domains of the N-terminal and the opposite effect of BcBBXs on BcHY5 was caused by C-terminal difference. The current results demonstrate the fine-tuned regulation of hypocotyl length via transcriptional regulation of BcMYBH by BcHY5-associated proteins and provide insights into Cruciferous hypocotyl length.
Interstitial granulomatous dermatitis in an infant with juvenile idiopathic arthritis
malek ben slimane
Takwa Bacha

malek ben slimane

and 5 more

May 26, 2022
Interstitial granulomatous dermatitis (IGD) is an uncommon entity characterized histologically by an interstitial granulomatous infiltrate. Juvenile idiopathic arthritis (JIA) is the most common rheumatic disease of childhood. We describe an infantt with JIA who developed an IGD. Physicians should be aware of this uncommon association.
Development of Contained Cerebrospinal Fluid Leak Associated with Changes in Atmosphe...
Luis Avellaneda
Lorena Garcia

Luis Avellaneda

and 2 more

May 26, 2022
Decompressive craniectomy is a measure in the management of intracranial hypertension due to injuries that dont respond to initial measures. cranial defects may present multiple complications associated with management. Atmospheric pressure generates a force on adjacent brain parenchyma, conditioning dynamic alterations in cerebral and cerebrospinal flow.
Fulminant streptococcal infection with early immunoglobulin introduction resulting in...
Takanori Sato
Rie Oyama

Takanori Sato

and 2 more

May 26, 2022
Fulminant streptococcal infection with early immunoglobulin introduction resulting in a favourable outcome for both mother and new-born: A case reportTakanori Sato, Rie Oyama, Tsukasa BABADepartment of Obstetrics and GynecologyIwate Medical University2-1-1 Ididori, Yaba-cho, Shiwa-gunIwateTel: 81-19-613-7111028-3695, JapanCo-author: Rie Oyama.E mail: oyamariegm@gmail.comRunning title: Successful treatment of STSS with immunoglobulinCase reportStreptococcal toxic shock syndrome (STSS) is Group A Streptococcus infection that causes rapidly progressive sepsis, disseminated intravascular coagulation (DIC), and multiple organ failure. STSS is the most common cause of sepsis-related maternal mortality1. Early diagnosis and intervention are important, but few reports on immunoglobulin as an adjunctive therapy. The cytokine production is elevated during pregnancy2, suppressing the cytokine storm is more important in sepsis caused by STSS in pregnant women than non-pregnant women, and anti-inflammatory immunoglobulin will likely be useful as an adjunctive therapy to improve maternal and infant prognosis. We report a case of STSS possibility treated using antimicrobial agents and immunoglobulin as adjuvant therapy. This patient of case report provided informed consent. We report a case of the potential of STSS treated with antibiotics and immunoglobulins as adjuvant therapy, and indicate the mechanism of effect of immunoglobulins on cytokine storm.A 37-year-old pregnant woman (gravid 5, para3) woman with a history of WPW syndrome and chronic thyroiditis. The patient had sore throat and fever of 39 °C on 32 +1 weeks, who was admministred in our hospital. At 32 + 4 weeks, her blood pressure and pulse were 79/48 mmHg and 140bpm, SpO2, 98% (oxygen mask, 6 L/min). Cardiotocography revealed delayed transient bradycardia, and we suspected septic shock and foetal insufficiency. Blood tests: WBC 14,740/μL, platelet 9.2 ×104/μL, C-reactive protein 11.1 mg/dL. Her qSOFA score: 1 (respiratory rate: >22 breaths/min), but her National Early Warning Score was 9 (respiratory rate, ≥25; oxygen demand, systolic blood pressure 101-110, heart rate ≥131/min), which is a warning value and corresponds to symptoms of sepsis due to STSS. Therefore, the antimicrobial agent was changed from cefepime to a combination of piperacillin and clindamycin, and an emergency caesarean section was performed 3 houre after admmited at our department. The baby was 2320 g, Apgar score, 1points/3 points (1 minute/5 minutes),umbilical artery blood pH 7.28. Obstetric DIC score was 3 points. Placental histopathology revealed stage 1 chorioamnionitis, but noGroup A streptococcal aggregation in the interchorionic space. On the second postoperative day, we were informed that Group A Streptococcus was detected in pharyngeal and blood cultures at the previous hospital, and antibacterial therapy with piperacillin and clindamycin for STSS and immunoglobulin were continued. Noradrenaline was also started as she had trouble maintaining her blood pressure on the first postoperative day, and dobutamine was added on the third postoperative day. On the fourth postoperative day, her respiratory condition worsened and bilateral diffuse frosted glass shadows were observed on chest radiography. Bilateral pleural effusions and pleural thickening were observed on computed tomography. Respiratory therapy with nasal high flow (NHF) was initiated. The patient was weaned from the NHF and switched to nasal cannula oxygenation on postoperative day 7. Oxygen administration was discontinued on postoperative day 15, and the patient was discharged on postoperative day 21 with improved bilateral diffuse frosted margins on chest radiographyDiscussionIn this case, STSS developed during pregnancy, but early delivery of the baby, antimicrobial therapy, and concomitant use of immunoglobulin from the early postoperative period onward resulted in a good outcome for both the mother and baby. In the field of obstetrics, perinatal STSS was described as “a condition that develops in pregnant women in the last trimester of pregnancy due to hematogenous myometrial infection mainly originating from the upper respiratory tract that induces labour pain and rapidly progresses to septic shock, resulting in a high rate of foetal and maternal death” in 20013,4. There is a trend toward poor prognosis for both the mother and new-born. In Japan, 24 (7.5%) of 317 maternal deaths were due to sepsis, and 13 (53.4%) were due to Group A Streptococcus infection between 2010 and 2016. A 2019 proposal by the Division of Medical Safety of the Japanese Society of Obstetricians and Gynaecologists stated that a modified Centor score should be used for pregnant women to facilitate early medical intervention and reduce maternal deaths due to STSS5. Penicillin and clindamycin are the basic antimicrobial agents of choice for STSS, and combinations containing clindamycin effectively suppress exotoxins and TNF-α and promote phagocytosis by inhibiting M-protein synthesis6,7. Meta-analysis reported that adjunctive immunoglobulin administration was associated with a significant reduction in mortality in STSS patients treated with clindamycin in 20188.The mechanisms of cytokine production and perinatal STSS are shown in Figure 1. Antigens are normally absorbed by antigen-presenting cells, fragmented into peptides, then recognised by T-cell receptors via the major histocompatibility complex (MHC) class II, which activates T cells. In contrast, superantigens bind directly to MHC class II and T-cell receptors without being taken up by antigen-presenting cells and produce numerous cytokines9,10, causing a marked inflammatory reaction via exotoxin11 and leading to septic shock. The production of cytokines such as TNF and IL-1β is also elevated during pregnancy due to changes in monocyte subsets13, and cases of perinatal STSS are prone to cytokine storms.Immunoglobulins exert effects similar to those of opsonin, along with phagocytosis-promoting, superantigen-neutralizing, anti-inflammatory, and antibody-dependent cytotoxic effects, and suppresses proinflammatory cytokine production11,13,14. Immunoglobulins have become a standard anti-inflammatory therapy for Kawasaki disease15. In this case, maintaining blood pressure became difficult on the first postoperative day, and noradrenaline was initiated along with immunoglobulin to suppress the cytokine storm caused by perinatal STSS. Procalcitonin levels were elevated the day after the culture results were obtained from the previous physician (postoperative day 3), but quickly decreased thereafter, and immunoglobulin was discontinued on postoperative day 4. Procalcitonin is produced by endotoxins and proinflammatory cytokines such as TNF-α, IL-1, and IL-6 in cases of severe bacterial infection16,17, and thus indirectly reflects the inflammatory state in the body. Procalcitonin may be an indicator of inflammation reflecting hypercytokinemia in cases of Kawasaki disease, and effectively predicts immunoglobulin refractoriness18. In this case, the reduction in procalcitonin levels following concomitant immunoglobulin use reflected STSS control and cytokine storm suppression, suggesting that the concomitant use of immunoglobulin may have been effective.In this study, we encountered a case of a mother and infant whose lives were saved by delivering the infant early, combined with the use of maternal antimicrobial therapy and combined immunoglobulin administration. The usefulness of combined immunoglobulin administration in perinatal STSS should be studied to further improve maternal and infant prognosis.
4D Printing and Shape memory materials in Bone Tissue Engineering
Xinwei Zhang

Xinwei Zhang

May 26, 2022
1. Introduction
Fertility-sparing surgery for borderline ovarian Brenner tumor and subsequent childbi...
Giulia Garofalo
Dario Bucella

Giulia Garofalo

and 3 more

May 26, 2022
Borderline ovarian Brenner tumors are rare, mainly diagnosed manopause. We reported in a previous article the first pregnancy after a fertility sparing surgery. We now report the first baby birth after unilateral salpingo-oophorectomy for a borderline ovarian Brenner tumor and a review of the literature on fertility sparing surgery.
Nosocomial Pseudomonas aeruginosa meningitis after spinal anaesthesia treated effecti...
Johary Andriamamonjisoa
Etienne RAKOTOMIJORO

Johary Andriamamonjisoa

and 3 more

May 26, 2022
Beeing a life-threatening and rare event, we present here a nosocomial Pseudomonas aeruginosa meningitis after spinal anaesthesia treated effectively with the combination of Cefoperazone/Sulbactam and Ciprofloxacin. These drugs could be a therapeutic alternatives to treat this life threatening disease, especially in low income countries where reference treatments are unavailable.
Bipolar Ablation for Outflow Tract Ventricular Arrhythmias: When the Going gets Tough...
Anurut Huntrakul
Jackson Liang

Anurut Huntrakul

and 1 more

May 26, 2022
Bipolar Ablation for Outflow Tract Ventricular Arrhythmias: When the Going gets Tough, Two Catheters may be Better than One Anurut Huntrakul, MD1,2 and Jackson J. Liang, DO11 Electrophysiology Section, Division of Cardiology, Cardiovascular Center, University of Michigan Medical Center, Ann Arbor, MI 48109, USA.2 Division of Cardiovascular Medicine, Department of Medicine, Faculty of Medicine, Chulalongkorn University, King Chulalongkorn Memorial Hospital, Bangkok 10330, ThailandFunding: NoneDisclosures: None
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