[Clinical significance of monitoring NUP98::NSD1 fusion genes before and after allogeneic hematopoietic stem cell transplantation]

Objective: This study aimed to observe the dynamic changes of NUP98::NSD1 expression before and after allogeneic hematopoietic stem cell transplantation (allo-HSCT) . Moreover, the clinical value of measurable residual disease (MRD) was analyzed. Methods: Sixteen AML patients who were diagnosed with the NUP98::NSD1 fusion gene and received allo-HSCT at Peking University People's Hospital were included. The NUP98::NSD1 fusion gene and leukemia-associated immunophenotype (LAIP) were monitored before and after transplantation to evaluate their MRD status. Results: The median follow-up time for all patients was 526 days (139-1136 days) , with four patients (25.0%) experiencing hematological recurrence at a median of 474 days (283-607 days) after transplantation. Three patients (18.8%) died, two of whom (12.5%) died of leukemia recurrence. The median expression level of NUP98::NSD1 in newly diagnosed patients with complete data was 78.5% (18.9%-184.4%) at the time of initial diagnosis. The recurrence rate was higher in NUP98::NSD1-positive patients after transplantation, with 44.4% of patients experiencing recurrence, whereas no recurrence occurred in NUP98::NSD1-negative patients after transplantation. The area under the receiver operating characteristic curve predicted by the NUP98::NSD1 level after transplantation was 1.000 (95% confidence interval: 1.000-1.000, P=0.003) . Among the four patients with recurrence, NUP98::NSD1 was more sensitive than flow cytometry residual (FCM) and Wilms' tumor gene 1 (WT1) . Conclusions: The NUP98::NSD1 fusion gene can be used to evaluate the MRD status of allo-HSCT. NUP98::NSD1-positive patients after transplantation have a high relapse rate and poor prognosis. NUP98::NSD1 was more sensitive than FCM and WT1 in predicting posttransplant relapse.

[Comparison of prognostic significance between multiparameter flow cytometry and real-time quantitative polymerase chain reaction in the detection of minimal residual disease of Philadelphia chromosome-positive acute B lymphocytic leukemia before allogeneic hematopoietic stem cell transplantation]

目的

探讨多参数流式细胞术（MFC）与实时定量聚合酶链反应技术（RQ-PCR）两种方法检测费城染色体阳性（Ph⁺）急性B淋巴细胞白血病（B-ALL）患者异基因造血干细胞移植（allo-HSCT）前微小残留病（MRD）的预后意义。

方法

回顾性分析2014年7月至2018年2月在北京大学血液病研究所接受allo-HSCT的280例Ph⁺ B-ALL患者，同时用MFC和RQ-PCR法（检测BCR-ABL融合基因表达）检测移植前MRD。

结果

RQ-PCR与MFC检测MRD具有相关性（rs＝0.435，P<0.001）。MFC、RQ-PCR法检测移植前MRD的阳性率分别为25.7％（72/280）、60.7％（170/280）。移植前MFC-MRD阳性组患者移植后白血病3年累积复发率（CIR）明显高于MFC-MRD阴性组（23.6％对8.6％，P<0.001）。RQ-PCR检测BCR/ABL融合基因阳性组（RQ-PCR MRD阳性组）的3年CIR、非复发死亡（NRM）、无白血病生存（LFS）、总生存（OS）与BCR/ABL融合基因阴性组（RQ-PCR MRD阴性组）相比差异均无统计学意义（P>0.05）。移植前RQ-PCR MRD≥1％组比<1％组具有更高的3年CIR（23.1％对11.4％，P＝0.032）、更低的LFS率（53.8％对74.4％，P＝0.015）与OS率（57.7％对79.1％，P＝0.009）。多因素分析显示，移植前MFC-MRD阳性是影响移植后CIR的危险因素（HR＝2.488，95％CI1.216～5.088，P＝0.013），移植前RQ-PCR MRD≥1％是影响LFS（HR＝2.272，95％CI 1.225～4.215，P<0.001）、OS（HR＝2.472，95％ CI 1.289～4.739，P＝0.006）的危险因素。MFC检测MRD预测复发的敏感性、特异性、阳性预测值（PPV）、阴性预测值（NPV）分别为48.50％、77.56％、23.62％、87.16％。以RQ-PCR MRD≥1％预测复发的敏感性、特异性、PPV、NPV分别为23.00％、88.59％、17.15％、91.84％。移植前MFC-MRD阳性或RQ-PCR MRD≥1％二者任一成立为指标预测移植后复发的敏感性、特异性、PPV、NPV分别为54.29％、73.88％、45.70％、91.87％。

结论

MFC和RQ-PCR法检测移植前MRD水平均可预测Ph⁺ B-ALL患者移植预后。移植前MFC-MRD阳性是移植后复发的危险因素。联合使用两种方法（移植前MFC-MRD阳性状态或RQ-PCR MRD≥1％成立）可提高预测移植后复发的敏感性、阳性预测值与阴性预测值，有助于更好筛选出高危患者。

[Occurrence and related factors of preterm birth in Guangxi Zhuang Autonomous Region during 2017-2019]

Objective: To investigate the incidence of preterm birth in Guangxi Zhuang Autonomous Region and explore the related factors and their combined effects. Methods: The study subjects were women giving birth to live babies at the monitoring points of critical maternal hospital monitoring system in Guangxi Zhuang Autonomous Region from January 1, 2017 to December 31, 2019. The data of general characteristics (age and marital status), pregnancies (parity, number of previous cesarean delivery, the number of prenatal check and number of fetuses in this pregnancy) and disease conditions (placenta previa, placental abruption, hypertension, diabetes, anemia, and heart disease) were collected, and the incidence of preterm birth were calculated according to the definition of preterm birth set by WHO and China, respectively. Logistic regression model was used to explore the factors associated with premature birth and their combined effects. Results: According to definitions of WHO and China, the cumulative incidence of preterm birth in Guangxi from 2017 to 2019 was 7.45% (16 819/225 727) and 7.34% (16 559/225 727), respectively. Advanced age [≤34 years old as reference, OR (95%CI) of 35-39 and ≥40 years old were 1.36 (1.30-1.42) and 1.61 (1.50-1.74), respectively], unmarried (including divorced or widowed) [OR (95%CI): 1.28 (1.17-1.40)], primiparae [OR (95%CI): 1.34 (1.29-1.40)], previous cesarean section [no previous cesarean section as reference, OR (95%CI) of 1 and ≥2 times of previous cesarean section were 1.30 (1.24-1.36) and 1.85 (1.65-2.08), respectively], antenatal examination<8 [OR (95%CI): 2.72 (2.62-2.81)], multiple pregnancies [OR (95%CI): 15.00 (14.01-16.06)], placenta previa [OR (95%CI): 6.90 (6.35-7.50)], placental abruption [OR (95%CI): 8.18 (7.36-9.10)], gestational hypertension [OR (95%CI): 2.29 (2.17-2.42)], gestational diabetes mellitus [OR (95%CI): 1.43 (1.37-1.49)], anemia [OR (95%CI): 1.10 (1.07-1.14)], and heart diseases [OR (95%CI): 2.98(2.43-3.65)] were all positively correlated with preterm birth. The risk of preterm birth in pregnant women exposed to 1, 2, 3, 4, 5, 6 and ≥7 preterm birth related factors was 1.51, 2.29, 4.49, 9.69, 20.87, 46.88 and 192.11 times that of non-exposed women, respectively (all P values<0.001). Conclusion: Preterm birth is associated with maternal general characteristics, pregnancy and disease status, and the combined effect of preterm birth related factors significantly increases the risk of preterm birth.

Polarization-free second-order nonlinear frequency conversion using the optical superlattice

We propose a universal and practical scheme to realize polarization-free second-order nonlinear frequency-conversion processes, including sum-frequency generation, difference-frequency generation, and optical parametric amplification. This scheme is based on the optical superlattice with a noncritical phase-matching condition, which is suitable for optical integration. A chirped dual-period structure is proposed to ensure the efficiency and stability of the conversions.

Poling quality evaluation of optical superlattice using 2D Fourier transform method

In this article we develop a method to evaluate the poling quality of optical superlattice (OSL) based on two-dimensional (2D) Fourier transform. To demonstrate this method, -Z or +Z face etched OSL samples with desired patterns are fabricated by standard electric field poling technique. By analyzing the processed micrograph of the etched surfaces, the magnitude of the reciprocal vectors of the OSL are calculated directly and rapidly. Second harmonic generation (SHG) experiment is performed to validate the evaluation result.

Frequency self-doubling optical parametric amplification: noncollinear red-green-blue light-source generation based on a hexagonally poled lithium tantalate

Simultaneous generation of noncollinear red, green, and blue light from a single hexagonally poled lithium tantalate is reported. It results from the frequency self-doubling optical parametric amplification process, a process of second-order harmonic generation cascaded optical parametric amplification in a single-pass setup. The temperature and spectrum detuning characters of each cascaded quasi-phase-matching process are studied. This unique red-green-blue light source has potential applications in laser display and other laser industries.

Apoptosis in the in vivo mammalian forebrain

Apoptosis is a word originally introduced by Kerr, Wyllie, and colleagues for a cell death process they defined in terms of its ultrastructural appearance in nonneuronal cells from various tissues. There are very few studies providing detailed ultrastructural criteria for recognizing neuronal apoptosis in the in vivo mammalian brain. In the absence of such criteria, the Kerr/Wyllie description pertaining to nonneuronal cells has served as a reference standard. However, contemporary neurobiologists typically rely on cell culture models for studying neuronal apoptosis, and these models are rarely validated ultrastructurally; rather they are assumed to be appropriate models based on unvalidated biochemical tests for apoptosis. Relying on evidence generated in such cell culture models or on nonspecific cytochemical tests applied to brain tissue, many authors have recently suggested that an apoptotic mechanism may mediate neuronal death in a wide variety of human neurodegenerative diseases. Whether the cell death process in neurodegenerative diseases meets ultrastructural criteria for apoptosis has been given very little consideration. Recently, several methods have been described for triggering extensive apoptotic neurodegeneration in the developing in vivo mammalian brain. These methods include head trauma or treatment with several types of drugs (NMDA antagonists, GABAA agonists, or ethanol). We have performed an ultrastructural analysis of the neuronal cell death process triggered in the cerebral cortex and thalamus by these several methods and compared it with physiological cell death (PCD), a prototypic example of neuronal apoptosis that occurs naturally in the developing brain. Our findings, which are reviewed herein, demonstrate that the types and sequence of changes induced by each of the above methods are identical to those that characterize PCD. This confirms that each of these methods produces bona fide in vivo apoptotic neurodegeneration, and it signifies that our description of this neuronal apoptotic process, which differs in some respects from the Kerr/Wyllie description of nonneuronal apoptosis, can serve as a useful reference standard for recognizing the characteristic changes that in vivo neurons undergo when they are dying by an apoptotic mechanism.

Crucial effects of coupling coefficients on quasi-phase-matched harmonic generation in an optical superlattice

Coupling of optical parametric processes in an optical superlattice through quadratic nonlinearity was analyzed theoretically. Solving the coupled equations, we found that efficient quasi-phase-matched third-harmonic (TH) generation depends not only on the magnitude of the coupling coefficients but also on their ratio. Theoretically, all the fundamental energy can be transferred to the TH at a particular ratio. In other cases, there exists an optimum condition that corresponds to a maximum TH conversion efficiency. The result is of practical importance for the design of TH devices.

Early development and developmental plasticity of the fasciculus gracilis in the North American opossum (Didelphis virginiana)

The first objective of the present study was to ask when axons of the fasciculus gracilis reach the nucleus gracilis in the North American opossum (Didelphis virginiana). When Fast Blue (FB) was injected into the lumbar cord on postnatal day (PD) 1 and the pups were killed 2 days later, labeled axons were present within a distinct fasciculus gracilis at thoracic and cervical levels of the cord. When comparable injections were made at PD3 or 5 and the pups were allowed to survive for the same time period, a few labeled axons could be followed to the caudal medulla where they were located dorsal to the presumptive nucleus gracilis. In order to verify these observations and to determine if any of the axons which innervate the nucleus gracilis early in development originate within dorsal root ganglia, we also employed cholera toxin conjugated to horseradish peroxidase (CT-HRP) to label dorsal root axons transganglionically. When CT-HRP was injected into the hindlimb on PD1 and the pups were maintained for 1 day prior to death and HRP histochemistry, labeled axons were present within the fasciculus gracilis at thoracic and cervical levels, but they could not be traced into the medulla. When comparable injections were made on PD3, and the pups were maintained for 2 days, labeled axons were present within the caudal medulla. Our second objective was to determine whether axons of the fasciculus gracilis grow through a lesion of their spinal pathway during early development. In one group of animals, the thoracic cord was transected at PD5, 8, 12, 20 and 26 and bilateral injections of Fast Blue (FB) were made four segments caudal to the lesion 30-40 days later. After a 3-5 day survival, the pups were killed and perfused so that the spinal cord and brainstem could be removed and sectioned for fluorescence microscopy. In all of the cases lesioned at PD5, axons of the fasciculus gracilis were labeled rostral to the site of transection and they could be followed to the nucleus gracilis. Evidence for growth of fasciculus gracilis axons into the caudal medulla was also seen in cases lesioned at PD8. In contrast, labeled axons were not observed rostral to the lesion when it was made at PD12 or at later stages of development. In order to verify that some of the axons which crossed the lesion originated within dorsal root ganglia, the thoracic cord was transected at PD5 in another group of animals and 7 days later, injections of CT-HRP were made into one of the hindlimbs. After a 3 day survival, labeled axons could be traced through the lesion site and into the caudal medulla. We conclude that axons of the fasciculus gracilis reach the nucleus gracilis by at least PD5 in the opossum and that they grow through a lesion of their spinal pathway when it is made at the same age or shortly thereafter. The critical period for such growth appears to end between PD8 and PD12.

Developmental plasticity of reticulospinal and vestibulospinal axons in the north American opossum, Didelphis virginiana

We have shown previously that rubral axons grow around a lesion of their spinal pathway in the North American opossum if it is made at early stages of development. In the present experiments, we have asked whether reticular and vestibular axons have the same ability. The spinal cord was hemisected at postnatal day 20, 12, or 5, well within the critical period for rubrospinal plasticity, and, approximately 30 days later, bilateral injections of fast blue were made about four segments caudal to the lesion. The pups were killed 4 or 5 days after the injections. In most of the animals lesioned on postnatal day 20, labeled neurons were not found in the medial part of the pontine reticular nucleus or the dorsal part of the lateral vestibular nucleus ipsilateral to the lesion. The spinal projections from both areas are exclusively ipsilateral. When the lesions were made at postnatal day 12 or 5, however, labeled neurons were present in both areas, suggesting that they supported axons that had grown caudal to the lesion. As was expected from previous studies, rubral neurons were labeled contralateral to the lesion in all three groups. In the opossum, as in other species, the red nucleus projects contralaterally. We conclude that reticular and vestibular axons, like axons from the red nucleus, grow around a lesion of their pathway during development and that the critical period for their plasticity ends earlier than that for rubrospinal axons.

The early development of major projections from caudal levels of the spinal cord to the brainstem and cerebellum in the gray short-tailed Brazilian opossum, Monodelphis domestica

The Brazilian short-tailed opossum, Monodelphis domestica, is born 14-15 days after copulation and is available for experimentation at stages of development corresponding to those which occur in utero in placental mammals. In the present study, we took advantage of the opossum's embryology to study the development of projections from caudal levels of the spinal cord to the brainstem and cerebellum using axonal tracing methods. In all cases, a 2-3 day survival time was used for axonal transport. When injections of Fast blue (FB) were made into caudal levels of the thoracic cord at postnatal day (PD) 1 or 2, axonal labeling could not be identified at supraspinal levels. When injections were made at PD3, however, labeled axons were found in the fasciculus gracilis at caudal medullary levels, within the ventrolateral medulla and pons, within an incipient inferior cerebellar peduncle, and within the cerebellar anlage. The dorsal root origin of at least some of the axons within the fasciculus gracilis was evidenced by the transganglionic transport of cholera toxin conjugated to horseradish peroxidase from the hindlimbs. After FB injections at PD7, a few labeled axons could be traced from the fasciculus gracilis into the nucleus gracilis and from the ventrolateral pathway to the inferior olive. Generally comparable results were obtained using wheat germ agglutinin conjugated to horseradish peroxidase (WGA-HRP). In cases injected with FB at PD9, the pattern of brainstem labeling was adult-like. Although labeled axons were present within the cerebellum of animals injected with FB on PD3, they were limited to the marginal zone. Axonal labeling was present within an identifiable internal granular layer in cases injected with either FB or WGA-HRP at PD16, and it appeared to be limited to specific bands which foreshadowed those seen at later stages of development and in the adult animal. In some cases, labeled axons were present within the molecular layer where they were not seen in the adult animal. Our results provide a timetable for the normal development of projections from caudal levels of the spinal cord to the brainstem and cerebellum in Monodelphis and show that such development occurs postnatally rather than prenatally, as in placental mammals.

The origins of supraspinal projections to the cervical and lumbar spinal cord at different stages of development in the gray short-tailed Brazilian opossum, Monodelphis domestica

We have used the retrograde transport of Fast blue (FB) to study the origins of supraspinal projections to the lumbar and cervical spinal cord at different stages of development in the Brazilian, short-tailed opossum, Monodelphis domestica. Monodelphis was chosen for study because its young are born in a very immature state, 14-15 days after copulation, making it possible to manipulate its nervous system in an embryonic state without intra-uterine surgery. When injections of FB were made into the lumbar cord at postnatal day (PD) 1, neurons were labeled within several areas of the reticular formation (the retroambiguus nucleus, the ventral and dorsal reticular nuclei of the medulla, the gigantocellular reticular nucleus, the lateral paragigantocellular reticular nucleus, and the pontine reticular nucleus), the presumptive coeruleus complex, and the lateral vestibular nucleus. In many cases, labeled neurons were also found within the caudal raphe and the presumptive interstitial nucleus of the medial longitudinal fasciculus. The results of immunocytochemical studies provided evidence for catecholaminergic and serotoninergic neurons in the brainstem at PD1 and for axons of both phenotypes in the spinal cord. By PD3, labeled neurons were found within the ventral gigantocellular and ventral pontine nuclei of the reticular formation, the spinal trigeminal nucleus, and the presumptive paraventricular nucleus of the hypothalamus. When injections were made at PD4, neurons were also labeled within the medial and inferior vestibular nuclei, the red nucleus, the mesencephalic nucleus of the trigeminal nerve, the presumptive nucleus of Edinger-Westphal and the lateral hypothalamus. By at least PD7, the pattern of supraspinal labeling was similar to that obtained at older ages and in the adult animal. When FB was injected into the cervical cord at PD1, neurons were labeled in all of the areas labeled by lumbar injections at the same age and in larger numbers. In addition, labeled neurons were found within the ventral gigantocellular and spinal trigeminal nuclei. When cervical injections were made at PD15, labeled neurons were found within the deep cerebellar nuclei and amygdala and by PD17 they were also present within the superior colliculus and cerebral cortex. In some cases, cortical labeling was present outside the areas labeled by comparable injections in adult animals.(ABSTRACT TRUNCATED AT 400 WORDS)