Case Report: A Very Low Birth Weight Female Infant With Congenital Bilateral Periventricular Leukomalacia, Born to a Mother With Coronavirus Disease 2019.

A 26-year-old primipara woman with COVID-19 performed an emergency Cesarean section due to further hypoxemia at 28 weeks 5/7 days gestation. The female neonate was born weighing 1,347 gram with an Apgar score of four at 1 min, three at 5 min, and eight at 10 min. RT-PCR from nasopharyngeal swabs for COVID-19 were performed at birth, 24 h, and 48 h after birth, all of which were negative. On head ultrasound bilateral cystic lesions were found in the anterior horn of the lateral ventricles at birth. A brain magnetic resonance imaging (MRI) test at 56 days of life (corrected 36 weeks and 6/7 days) revealed cystic lesions with T1 low signal, T2 high signal, and T2 Flair high signal around the anterior horn of the lateral ventricle and We diagnose it as Grade 2 periventricular leukomalacia (PVL). She was discharged on day 64 of life, with no abnormality on exam. While the majority of neonates born to women with COVID-19 during pregnancy have favorable outcome, we report a case of a neonate with Grade 2 periventricular leukomalacia and this should prompt clinicians to monitor fetal cerebral function and structure shortly after birth.

Safety and efficacy of a 52-mg levonorgestrel-releasing intrauterine system in women with cardiovascular disease.

AIM: We sought to examine the safety and efficacy of a 52-mg levonorgestrel-releasing intrauterine system (LNG-IUS), and to evaluate the changes in biomarkers of infection, anemia and cardiovascular conditions after LNG-IUS insertion in women with cardiovascular disease. METHODS: We prospectively followed women with a cardiovascular disease in whom a 52-mg LNG-IUS was inserted between 2009 and 2015. The primary outcome was the frequency of cardiovascular and gynecologic side effects due to the LNG-IUS over the year after LNG-IUS insertion. The secondary outcomes were the changes in menstrual blood loss and biomarkers, e.g., white blood cell count and the levels of C-reactive protein, hemoglobin and brain natriuretic peptide. We also evaluated the 24-month continuation rate of LNG-IUS. RESULTS: A total of 34 women were prospectively followed-up, including two women with pulmonary hypertension. No cardiovascular side effects were identified during the 1 year after LNG-IUS insertion, other than one case of mild vasovagal reaction at insertion. Neither the white blood cell count nor the C-reactive protein value increased after LNG-IUS insertion. The menstrual blood loss was decreased in most subjects and the median hemoglobin levels increased significantly within 1 year after insertion (P < 0.001 and P = 0.002). Moreover, brain natriuretic peptide levels tended to decrease in correspondence with the hemoglobin elevation (P = 0.074). The 24-month LNG-IUS continuation rate was 97% (95% confidence interval 85-100). CONCLUSION: No clinically significant cardiovascular event was identified during the 1 year after 52-mg LNG-IUS insertion among women with cardiovascular disease. The 52-mg LNG-IUS may have specific favorable effects by decreasing the risk of iron deficiency anemia in these women.

Cardiomyopathy Phenotypes and Pregnancy Outcomes with Left Ventricular Noncompaction Cardiomyopathy.

Little is known about pregnancies of left ventricular noncompaction cardiomyopathy (LVNC), much less cases in which LVNC was definitively diagnosed prepregnancy. We report the cases of three pregnant Japanese women definitively diagnosed with LVNC prepregnancy. Case 1 presented LVNC with restrictive phenotype. Her pregnancy was terminated due to exacerbated pulmonary hypertension and low output status at 30 weeks' gestation. Case 2 presented isolated LVNC with nonsustained ventricle tachycardia. A cesarean section was performed at 36 weeks' gestation because of placenta previa. Case 3 presented dilated LVNC. Labor induction was performed because of decreased left ventricular ejection fraction, leading to a vaginal delivery at 37 weeks' gestation. In all cases, no thromboembolic event was identified during pregnancy; two patients received anticoagulants. We reviewed all English-literature cases of pregnant women definitively diagnosed with LVNC prepregnancy to analyze causes of adverse pregnancy outcomes and the necessity of anticoagulation. Four of the six pregnancies identified were terminated due to exacerbated cardiomyopathy phenotypes and not complications due to noncompaction itself, resulting in three cases' preterm deliveries. No thromboembolic event was identified by maintenance of the anticoagulation strategy determined prepregnancy. In pregnancies with LVNC, the possibility of a severe cardiac event and the indications for termination of the pregnancy can depend on the cardiomyopathy phenotypes, not noncompaction itself. Anticoagulation only because of the pregnancy itself may be redundant. In the management of LVNC during pregnancy, close monitoring of the condition of different phenotypes and reassessment of the necessity of anticoagulation can contribute to the pregnancy outcome.

A high dose intravenous immunoglobulin therapy for women with four or more recurrent spontaneous abortions.

Recurrent spontaneous abortion (RSA) may have immunological etiology. The aim of this study was to assess the efficacy of a high dose intravenous immunoglobulin (HIVIg) therapy, in which 20 g of intact type immunoglobulin was infused daily for 5 days during early gestation, for women who had a history of four or more consecutive spontaneous abortions of unexplained etiology. A total of 60 pregnant RSA women underwent HIVIg therapy, and the pregnancy outcome was assessed. The live birth rate was 73.3% (44/60). Fifteen pregnancies ended in spontaneous abortion, and one ended in intrauterine fetal death. In 11 of the 15 spontaneous abortions, fetuses had abnormal chromosome karyotype. When the 11 pregnancies with abnormal chromosome karyotype were excluded, the live birth rate was as high as 89.8% (44/49). The HIVIg therapy may be effective for severe cases of unexplained RSA.

Rab27b regulates c-kit expression by controlling the secretion of stem cell factor.

Rab27b, a subfamily of Rab27 small GTPases, was originally identified in platelets. However, the role of Rab27b in megakaryocytic lineage cells remains unknown. Here, using a human megakaryoblastic cell line, CMK, we show that Rab27b negatively regulates c-kit-expression. We found that transfection of shRNA-Rab27b into CMK cells led to specific increase in the amount of the receptor-type tyrosine kinase c-kit. To elucidate the molecular mechanisms by which Rab27b regulates c-kit expression, we analyzed the dynamics of c-kit by the stimulation with its ligand, stem cell factor (SCF). We found that cell surface expression of c-kit was promptly reduced and rapidly degraded in both CMK and Rab27b-knockdown CMK cells. Pretreatment with a lysosome inhibitor bafilomycin suppressed the degradation of c-kit, indicating that c-kit expression is controlled by SCF-induced endolysosomal degradation system. We therefore focused on the potential involvement of SCF in Rab27b-mediated effects on c-kit expression levels. We found that autocrine secretion of SCF was downregulated in Rab27b-knockdown cells as compared with parental CMK cells. These results suggest that Rab27b negatively regulates the cell surface expression of c-kit via secretion of SCF and that ligation of SCF leads to the endolysosomal degradation system of c-kit.

Resection of giant liver hemangioma in a pregnant woman with coagulopathy: Case report and literature review.

BACKGROUND: Hemangioma is a common benign tumor in the liver and usually asymptomatic. Scanty evidence concerning treatment modality of symptomatic hemangioma during pregnancy exists. CASE: A 35 year-old woman with giant hepatic cavernous hemangioma developed consumption coagulopathy due to the enlarged tumor, and underwent danaparoid therapy from 5 weeks of gestation (GW). Magnetic resonance image revealed giant hemangioma with 20 cm in diameter in the right lobe of the liver. A surgical operation of liver resection was successfully performed at 16 GW. Thereafter, the coagulopathy disappeared. She delivered a healthy male infant at 36 GW. CONCLUSION: This is the first case report of surgical resection therapy for giant liver hemangioma during pregnancy.

Rab27a negatively regulates phagocytosis by prolongation of the actin-coating stage around phagosomes.

Rab27a, a Rab family small GTPase, is involved in the exocytosis of secretory granules in melanocytes and cytotoxic T-cells. Rab27a mutations cause type 2 Griscelli syndrome, which is characterized by immunodeficiency, including uncontrolled macrophage activation known as hemophagocytic syndrome. However, the role of Rab27a in phagocytosis remains elusive. Here, using macrophage-like differentiated HL-60 cells and C3bi-opsonized zymosan as a pathogen-phagocyte model, we show that Rab27a negatively regulates complement-mediated phagocytic activity in association with F-actin remodeling. We found that transfection of Rab27a shRNA into HL-60 cells enhances complement-mediated phagocytosis. To clarify the mechanisms underlying the elevated phagocytosis in Rab27a knockdown cells, we analyzed the process of phagosome formation focusing on F-actin dynamics: F-actin assembly, followed by F-actin extension around the particles and the subsequent degradation of F-actin, leading to internalization of the particles enclosed in phagosomes. Microscopic analysis revealed that these actin-related processes, including F-actin coating and F-actin degradation, proceed more rapidly in Rab27a knockdown cells than in control HL-60 cells. Both elevated phagocytosis and accelerated F-actin remodeling were restored by expression of rescue-Rab27a and Rab27a-Q78L (GTP-bound form), but not by Rab27a-T23N (GDP-bound form). Furthermore, an increased accumulation of Coronin 1A surrounding F-actin coats was observed in Rab27a knockdown cells, suggesting that the function of Coronin 1A is related to the regulation of the F-actin coating. Our findings demonstrate that Rab27a plays a direct regulatory role in the nascent process of phagocytosis by prolongation of the stage of actin coating via suppression of Coronin 1A. This study may contribute to an explanation of the underlying mechanisms of excessive phagocytosis observed in Griscelli syndrome.

ATP-induced osteoclast function: the formation of sealing-zone like structure and the secretion of lytic granules via microtubule-deacetylation under the control of Syk.

Osteoclasts are bone-resorbing cells which play an exclusive role in bone remodeling, but the molecular mechanisms of osteolysis, how osteoclasts are activated and how the lytic granules are finally released towards the bone matrix are poorly understood. Here we show that an energy molecule ATP induces osteolysis via P2X(7)-nucleotide receptor and that deacetylation of alpha-tubulin is essential for the whole process of osteolysis under the control of a tyrosine kinase Syk. By developing a traceable and reproducible in vitro analyzing system for osteoclast function, we found that ATP-signaling gives rise to two events simultaneously (i) cytoskeletal reorganization for the formation of sealing zones, ring-like adhesion structures which delimit the contact surface, and (ii) the delivery and secretion of lytic granules towards the delimited site on the matrix. We further found that deacetylation of alpha-tubulin is a critical reaction for osteoclast function. Pharmacological inhibition of alpha-tubulin deacetylation resulted in (i) failure of the sealing-zone like structure formation and (ii) ceased secretion of lytic granules. Additionally, kinetics of deacetylation was found to be regulated by Syk. These data suggest a novel P2X(7) microtubular regulation pathway related to Syk for a therapeutic target in osteolytic diseases.

Protein-tyrosine kinase Syk is required for pathogen engulfment in complement-mediated phagocytosis.

The protein tyrosine kinase Syk plays a central role in Fcgamma receptor-mediated phagocytosis in the adaptive immune system. We show here that Syk also plays an essential role in complement-mediated phagocytosis in innate immunity. Macrophage-like differentiated HL60 cells and C3bi-opsonized zymosan comprised the pathogen-phagocyte system. C3bi-opsonized zymosan particles promptly attached to the cells and were subsequently engulfed via complement receptor 3. During this process, Syk became tyrosine phosphorylated and accumulated around the nascent phagosomes. The transfer of Syk-siRNA or dominant-negative Syk (DN-Syk) into HL60 cells resulted in impaired phagocytosis. Quenching assays using fluorescent zymosan revealed that most of the attached zymosan particles were located inside parental HL60 cells, whereas few were ingested by the mutant cells. These data indicated that Syk is required for the engulfment of C3bi-opsonized zymosan. During C3bi-zymosan-induced phagocytosis, actin accumulation occurred around phagosomes and was followed by depolymerization, and further RhoA was activated together with tyrosine phosphorylation of Vav. These responses including the actin remodeling were suppressed in Syk-siRNA- or DN-Syk-expressing cells. Our results demonstrated that Syk plays an indispensable role in complement-mediated phagocytosis by regulating both actin dynamics and the RhoA activation pathway and that these functions of Syk lead to phagosome formation and pathogen engulfment.

Protein-tyrosine kinase, Syk, is required for CXCL12-induced polarization of B cells.

Cell polarization and migration in response to CXCL12 is essential for hematopoiesis. To investigate the role of Syk in CXCL12/CXCR4-induced signaling, wild-type Syk or its dominant-negative form (DN-Syk) was introduced in mouse pro-B cells, BAF3. With CXCL12 stimulation, BAF3 cells became polarized with the formation of a leading edge and contractile uropod at the rear end with increased motility. Overexpression of wild-type Syk caused enhanced polarization, whereas DN-Syk inhibited cell polarity due to the loss of contractile structure at the rear end, and the altered phenotype was enhanced after CXCL12 stimulation. Motility of mutant BAF3 containing DN-Syk increased independent of CXCL12 stimulation. As beta1 integrin-mediated cell adhesion was inhibited, decreased adhesion might promote motility. CXCL12 stimulation led to prompt activation of RhoA, but expression of DN-Syk suppressed RhoA activation. These results demonstrate that Syk participates in CXCL12-induced cell polarization, which occurs in concert with cell adhesion mediated by beta1 integrin.