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International Journal of Clinical Oncology - This multi-institutional clinical trial evaluated the feasibility of intensity-modulated radiotherapy (IMRT) for patients with locally advanced...  相似文献   
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The aim of this study was to investigate the association between changes in the levels of vascular endothelial growth factors (VEGFs) after treatment with bevacizumab and gemcitabine (Bev-Gem) and the clinical outcome. Platinum-resistant ovarian cancer patients treated with Bev-Gem therapy at our hospital between 2014 and 2018 were identified. Serum VEGF levels at the first and second treatment cycle were measured by ELISA. All patients were categorized into two groups—patients with > 50% decrease in serum VEGF-A levels (Group A) and patients with < 50% decrease serum VEGF-A levels (Group B). The association between clinical outcome and serum VEGF levels was investigated between the two groups. Among 18 patients, 10 were in Group A and 8 in Group B. Group A exhibited a lower response rate (0% vs.75% p < 0.01) and clinical benefit rate (60% vs.100% p = 0.02) than Group B. The median serum VEGF-A level of Group A before the first cycle of Bev-Gem therapy was higher than that in Group B (61.2 vs. 3.7 pg/mL, p < 0.01). Group A exhibited worse PFS (7 vs., 10 months, p < 0.01) and OS (17 vs. 26 months, p = 0.04) than Group B. There were more patients with > 10% increase in serum VEGF-B levels in Group A than in Group B (p < 0.01). The rapid decrease in VEGF-A levels and the resultant increase in serum VEGF-B levels might be associated with an unfavorable clinical outcome. Large-scale studies are needed to further examine these results.  相似文献   
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Diapause represents a major developmental switch in insects and is a seasonal adaptation that evolved as a specific subtype of dormancy in most insect species to ensure survival under unfavorable environmental conditions and synchronize populations. However, the hierarchical relationship of the molecular mechanisms involved in the perception of environmental signals to integration in morphological, physiological, behavioral, and reproductive responses remains unclear. In the bivoltine strain of the silkworm Bombyx mori, embryonic diapause is induced transgenerationally as a maternal effect. Progeny diapause is determined by the environmental temperature during embryonic development of the mother. Here, we show that the hierarchical pathway consists of a γ-aminobutyric acid (GABA)ergic and corazonin signaling system modulating progeny diapause induction via diapause hormone release, which may be finely tuned by the temperature-dependent expression of plasma membrane GABA transporter. Furthermore, this signaling pathway possesses similar features to the gonadotropin-releasing hormone (GnRH) signaling system for seasonal reproductive plasticity in vertebrates.

To ensure survival under unfavorable environmental conditions and synchronize populations, most insect species enter diapause, which is a seasonal adaptation that evolved as a specific subtype of dormancy (1, 2). Diapause is not a passive response to changing conditions but rather an actively induced state that precedes adverse natural situations. Therefore, this diapause phenotype is accompanied by changes in energy metabolism or storage to improve cold/stress tolerance in later life stages, or progeny via reproductive switch (3). Although it has been generally suggested that brain/neuroendocrine systems are associated with this seasonal reproductive plasticity in both vertebrates and invertebrates (3, 4), the hierarchical relationship of the molecular mechanisms involved in the perception of environmental signals to integration into morphological, physiological, behavioral, and reproductive responses, known as the diapause syndrome, remains unclear (3).The silkworm Bombyx mori is a typical insect that arrests normal development during early embryogenesis, which is accompanied by metabolic changes in diapause (5, 6). The development of diapause-destined embryos is arrested during the G2 cell cycle stage immediately after the formation of the cephalic lobe and telson and sequential segmentation of the mesoderm (7). The bivoltine strain of B. mori has two generations per year, and progeny diapause is transgenerationally induced as a maternal effect and is determined by the environmental temperature, photoperiod, and nutrient conditions during embryonic and larval development of the mother (5, 6). The temperature signal during the mother’s embryonic development predominantly affects diapause determination, even if silkworms of the bivoltine Kosetsu strain are exposed to all cases of photoperiods during embryonic and larval development. In the Kosetsu strain, when eggs are incubated at 25 °C under continuous darkness, the resultant female moths (25DD) lay diapause eggs in almost all cases. In contrast, incubation of eggs at 15 °C in dark condition results in moths (15DD) that lay nondiapause eggs in almost all cases (6).Embryonic diapause is induced by the diapause hormone (DH) signaling pathway, which consists of highly sensitive and specific interactions between a neuropeptide, DH, and DH receptor (DHR) (6, 8). DH is exclusively synthesized in seven pairs of neurosecretory cells (DH-PBAN–producing neurosecretory cells [DHPCs]) located within the subesophageal ganglion (SG) in the mother’s generation (6). DH is released into the hemolymph during pupal–adult development and acts on the DHR, which belongs to the G protein-coupled receptors (GPCRs) (9). DH levels in the hemolymph are higher in the 25DD than 15DD pupae in the middle of pupal–adult development when the developing ovaries are sensitive to DH (6). Furthermore, the embryonic Bombyx TRPA1 ortholog (BmTRPA1) acts as a thermosensitive channel that is activated at temperatures above ∼21 °C and affects diapause induction through DH release (10). However, there remain questions about the thermal information that is received by BmTRPA1 and linked to DH signaling to induce diapause.From the 1950s, it has been suggested that the DH release was controlled by signals derived from certain region(s) in the brain based on surgical experiments, such as midsagittal bisection or transection (1113). Especially, the operation in nondiapause producers changed them to diapause producers while transection of the protocerebrum had no effect on the diapause producers. These surgical results suggested the involvement of the protocerebrum in the inhibitory control of DH secretion (12, 14). Furthermore, the accumulation of the ovarian 3-hydroxykynurenine (3-OHK) pigment that accompanies the diapause syndrome was affected by injection with γ-aminobutyric acid (GABA) and the plant alkaloid picrotoxin (PTX), which is a widely used ionotropic GABA and glycine receptor antagonist (15, 16), and the selective ionotropic GABA receptor (GABAR) antagonist bicuculline. This suggests that a GABAergic neurotransmission via ionotropic GABAR is involved in DH secretion, which may be active in nondiapause producers but inactive in diapause producers throughout the pupal–adult development (14, 17). In general, ionotropic GABAR is composed of homo- or hetero-pentameric subunits. All known GABAR subunits display a similar structural scheme, with a large N-terminal extracellular domain involved in the formation of a ligand-binding pocket and a pore domain made of four transmembrane alpha-helices (TM1–TM4) (16, 18). Four homologous sequences of the ionotropic GABAR subunit genes were identified as RDL, LCCH3, GRD, and a GRD-like sequence named 8916 in various insects (19). However, the in vivo physiological roles of both signals derived from the brain and the GABAergic pathway in diapause induction have not been previously investigated.Corazonin (Crz) is an undecapeptide neurohormone sharing a highly conserved amino acid (a.a.) sequence across insect lineages and is involved in different physiological functions, such as heart contraction (20), stress response (21, 22), various metabolic activities (2325), female fecundity (26), melanization of locust cuticles (27), regulation of ecdysis (28, 29), and control of caste identity (30). Moreover, Crz belongs to the gonadotropin-releasing hormone (GnRH) superfamily alongside adipokinetic hormone (AKH) and AKH/Crz-related peptide (ACP). Duplicates of an ancestral GnRH/Crz signaling system occurred in a common ancestor of protostomes and deuterostomes through coevolution of the ligand receptor (31, 32).Herein, we demonstrated that the hierarchical pathway consists of a GABAergic and Crz signaling system modulating progeny diapause induction by acting on DH release. We propose that the PTX-sensitive GABAergic signal may act to chronically suppress Crz release in dorsolateral Crz neurons (under nondiapause conditions) and that diapause conditions (or PTX injection) inhibits GABAergic signaling, resulting in accelerated Crz release, which in turn induces DH release. GABA signaling may be finely tuned by the temperature-dependent expression of the plasma membrane GABA transporter (GAT), which differs between the 25DD and 15DD conditions. Furthermore, this signaling pathway possesses similar features to the GnRH signaling system with respect to seasonal reproductive plasticity in vertebrates.  相似文献   
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Rescue therapy for gastrointestinal (GI) refractory bleeding, perforation, and fistula has traditionally required surgical interventions owing to the limited performance of conventional endoscopic instruments and techniques. An innovative clipping system, the over‐the‐scope clip (OTSC), may play an important role in rescue therapy. This innovative device is proposed as the final option in endoscopic treatment. The device presents several advantages including having a powerful sewing force for closure of GI defects using a simple mechanism and also having an innovative feature, whereby a large defect and fistula can be sealed using accessory forceps. Consequently, it is able to provide outstanding clinical effects for rescue therapy. This review clarifies the current status and limitations of OTSC according to different indications of GI refractory disease, including refractory bleeding, perforation, fistula, and anastomotic dehiscence. An extensive literature search identified studies reported 10 or more cases in which the OTSC system was applied. A total of 1517 cases described in 30 articles between 2010 and 2018 were retrieved. The clinical success rates and complications were calculated overall and for each indication. The average clinical success rate was 78% (n = 1517) overall, 85% for bleeding (n = 559), 85% (n = 351) for perforation, 52% (n = 388) for fistula, 66% (n = 97) for anastomotic dehiscence, and 95% (n = 122) for other conditions, respectively. The overall and severe OTSC‐associated complications were 1.7% (n = 23) and 0.59% (n = 9), respectively. This review concludes that the OTSC system may serve as a safe and productive device for GI refractory diseases, albeit with limited success for fistula.  相似文献   
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Context: We sought to describe our experience with the Hybrid Assistive Limb® (HAL®) for active knee extension and voluntary ambulation with remaining muscle activity in a patient with complete paraplegia after spinal cord injury.

Findings: A 30-year-old man with complete paraplegia used the HAL® for 1 month (10 sessions) using his remaining muscle activity, including hip flexor and upper limb activity. Electromyography was used to evaluate muscle activity of the gluteus maximus, tensor fascia lata, quadriceps femoris, and hamstring muscles in synchronization with the Vicon motion capture system. A HAL® session included a knee extension session with the hip flexor and voluntary gait with upper limb activity. After using the HAL® for one month, the patient’s manual muscle hip flexor scores improved from 1/5 to 2/5 for the right and from 2/5 to 3/5 for the left knee, and from 0/5 to 1/5 for the extension of both knees.

Conclusion/clinical relevance: Knee extension sessions with HAL®, and hip flexor and upper-limb-triggered HAL® ambulation seem a safe and feasible option in a patient with complete paraplegia due to spinal cord injury.  相似文献   

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