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Abstract Circulating cell-free DNA (cfDNA) assays for monitoring individuals with cancer typically rely on prior identification of tumor-specific mutations. Here, we develop a tumor-independent and mutation-independent approach (DELFI-tumor fraction, DELFI-TF) using low-coverage whole genome sequencing to determine the cfDNA tumor fraction and validate the method in two independent cohorts of patients with colorectal or lung cancer. DELFI-TF scores strongly correlate with circulating tumor DNA levels (ctDNA) (r = 0.90, p

Probiotics are live microorganisms that offer potential benefits to their hosts and can occasionally influence behavioral responses. However, the detailed mechanisms by which probiotics affect the behavior of their hosts and the underlying biogenic effects remain unclear. Lactic acid bacteria, specifically Lactobacillus spp. are known probiotics. Drosophila melanogaster, commonly known as the fruit fly, is a well-established model organism for investigating the interaction between the host and gut microbiota in translational research. Herein, we showed that 5-day administration of Lactobacillus acidophilus (termed GMNL-185) or Lacticaseibacillus rhamnosus (termed GMNL-680) enhances olfactory-associative memory in Drosophila. Moreover, a combined diet of GMNL-185 and GMNL-680 demonstrated synergistic effects on memory functions. Live brain imaging revealed a significant increase in calcium responses to the training odor in the mushroom body β and γ lobes of flies that underwent mixed feeding with GMNL-185 and GMNL-680. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) and whole-mount brain immunohistochemistry revealed significant upregulation of lactate dehydrogenase (LDH) expression in the fly brain following the mixed feeding. Notably, the genetic knockdown of Ldh in neurons, specifically in mushroom body, ameliorated the beneficial effects of mixed feeding with GMNL-185 and GMNL-680 on memory improvement. Altogether, our results demonstrate that supplementation with L. acidophilus and L. rhamnosus enhances memory functions in flies by increasing brain LDH levels.

Background: The clinical value of therapeutic drug monitoring (TDM) for newer anti-seizure medications (ASMs) remains uncertain. This study aimed to assess the impact of newer ASM TDM on clinical decision making in patients with epilepsy. Methods: We retrospectively identified all plasma requests for newer ASM level measurement as part of routine clinical management in the outpatient departments of seven medical institutes across Taiwan between September 2016 and May 2019. Data collected from reviewed medical records included clinical and medication details, indications for TDM requests, test results, interpretation, and impact on patient management. Results: A total of 682 visits with 1051 plasma samples were included. The most frequently analyzed ASMs were levetiracetam (36.1%), oxcarbazepine (18.4%), and lamotrigine (12.0%). Reasons for TDM included poorly controlled seizures (55.3%), concerns about drug-drug interactions (12.3%), and suspicion of drug overdose (10.6%). 68.8% of samples were within the orienting therapeutic range, even for patients with poorly controlled seizures. TDM for non-adherence concerns showed 54.3% below the orienting therapeutic range, while ASM-related adverse events assessment only 8.9% showed levels exceeding the orienting therapeutic range. Following TDM results, 64.2% of cases had medication adjustments, mainly dosage increases. Overall, 55.9% of newer ASM TDM visits showed improved outcomes, including reduced seizures (47.5%) and fewer ASM-related side effects (8.4%). Conclusions: These findings suggest that appropriate utilization of TDM for newer ASMs provides clinical benefits in adjunct to complement clinical decision making in the management of epilepsy patients in a real-world clinical setting.

Advancing treatment to resolve human cognitive disorders requires a comprehensive understanding of the molecular signaling pathways underlying learning and memory. While most organ systems evolved to maintain homeostasis, the brain developed the capacity to perceive and adapt to environmental stimuli through the continuous modification of interactions within a gene network functioning within a broader neural network. This distinctive characteristic enables significant neural plasticity, but complicates experimental investigations. A thorough examination of the mechanisms underlying behavioral plasticity must integrate multiple levels of biological organization, encompassing genetic pathways within individual neurons, interactions among neural networks providing feedback on gene expression, and observable phenotypic behaviors. Model organisms, such as Drosophila melanogaster, which possess more simple and manipulable nervous systems and genomes than mammals, facilitate such investigations. The evolutionary conservation of behavioral phenotypes and the associated genetics and neural systems indicates that insights gained from flies are pertinent to understanding human cognition. Rather than providing a comprehensive review of the entire field of Drosophila memory research, we focus on olfactory associative reward memories and their related neural circuitry in fly brains, with the objective of elucidating the underlying neural mechanisms, thereby advancing our understanding of brain mechanisms linked to cognitive systems.

Background: Perampanel (PER) is a newly developed antiseizure medication (ASM). This study aimed to determine the utilization of therapeutic drug monitoring (TDM) for PER in a real-world clinical setting and investigate the influence of concomitant use of ASMs on the plasma concentration profile of PER. Method: We analyzed data from the Chang Gung Research Database, which is the largest multi-institutional electronic medical records database in Taiwan. The main outcomes were the comparisons of PER plasma concentration and the ratio of concentration to the weight-adjusted dose (C/D; [ng/mL]/[mg/kg/d]) among patients received TDM of different clinical indication and among different ASM co-medication subgroups. Results: Overall, 88 plasma samples were collected from 66 epilepsy patients treated with PER. The majority of patients (77.3 %) underwent PER TDM owing to poorly controlled seizures. There was a trend toward a higher plasma concentration and C/D ratio in those suspected of having PER toxicity owing to adverse events than of other indications. The PER concentration exhibited dose linearity. The mean PER plasma concentrations in patients co-medicated with enzyme-inducing ASMs were significantly lower than those in the patients who were not prescribed enzyme-inducing or enzyme-inhibiting ASMs, and co-medication with carbamazepine (CBZ) resulted in a significant reduction in the PER concentration. Conclusion: PER concentration exhibited a linear regression relationship with PER dose, and the plasma concentration of the drug was highly susceptible to the drug's interactions with enzyme-inducing ASMs. TDM with clear indication could help determine the influence of ASMs used concomitantly on PER concentrations and guide clinical adjustments.

Plasminogen activators, such as recombinant tissue-type plasminogen activators (rtPAs), while effective in treating thromboembolic diseases, often induce hemorrhagic complications due to non-specific enzyme activities in the systemic circulation. This study evaluated the targeting efficiency, efficacy, biodistribution, and potential toxicity of a rtPA covalently attached to chitosan-coated magnetic nanoparticles (chitosan-MNP-rtPA). The thrombolytic activity of a chitosan-MNP-rtPA was preserved by protection from an endogenous plasminogen activator inhibitor-1 (PAI-1) in whole blood and after circulation in vivo, as examined by thromboelastometry. Single-photon emission computed tomography (SPECT) demonstrated real-time retention of a 99mTc-MNP-rtPA induced by magnet application in a rat embolic model; an 80% reduction in rtPA dosage for a chitosan-MNP-rtPA with magnetic guidance was shown to restore blood flow. After treatment, iron deposition was observed in the reticuloendothelial systems, with portal edema and neutrophil infiltration in the liver at a ten-fold higher dose but not the regular dose. Nevertheless, no liver or renal toxicity was observed at this higher dose. In conclusion, the liver may still be the major deposit site of rtPA nanocomposites after targeted delivery; chitosan-coated MNPs are potentially amenable to target therapeutics with parenteral administration.

Thermosensation is critical for the survival of animals. However, mechanisms through which nutritional status modulates thermosensation remain unclear. Herein, we showed that hungry Drosophila exhibit a strong hot avoidance behavior (HAB) compared to food-sated flies. We identified that hot stimulus increases the activity of α'β' mushroom body neurons (MBns), with weak activity in the sated state and strong activity in the hungry state. Furthermore, we showed that α'β' MBn receives the same level of hot input from the mALT projection neurons via cholinergic transmission in sated and hungry states. Differences in α'β' MBn activity between food-sated and hungry flies following heat stimuli are regulated by distinct Drosophila insulin-like peptides (Dilps). Dilp2 is secreted by insulin-producing cells (IPCs) and regulates HAB during satiety, whereas Dilp6 is secreted by the fat body and regulates HAB during the hungry state. We observed that Dilp2 induces PI3K/AKT signaling, whereas Dilp6 induces Ras/ERK signaling in α'β' MBn to regulate HAB in different feeding conditions. Finally, we showed that the 2 α'β'-related MB output neurons (MBONs), MBON-α'3 and MBON-β'1, are necessary for the output of integrated hot avoidance information from α'β' MBn. Our results demonstrate the presence of dual insulin modulation pathways in α'β' MBn, which are important for suitable behavioral responses in Drosophila during thermoregulation under different feeding states.

Temperature has a significant effect on all physiological processes of animals. Suitable temperatures promote responsiveness, movement, metabolism, growth, and reproduction in animals, whereas extreme temperatures can cause injury or even death. Thus, thermosensation is important for survival in all animals. However, mechanisms regulating thermosensation remain unexplored, mostly because of the complexity of mammalian neural circuits. The fruit fly Drosophila melanogaster achieves a desirable body temperature through ambient temperature fluctuations, sunlight exposure, and behavioral strategies. The availability of extensive genetic tools and resources for studying Drosophila have enabled scientists to unravel the mechanisms underlying their temperature preference. Over the past 20 years, Drosophila has become an ideal model for studying temperature-related genes and circuits. This review provides a comprehensive overview of our current understanding of thermosensation and temperature preference in Drosophila. It encompasses various aspects, such as the mechanisms by which flies sense temperature, the effects of internal and external factors on temperature preference, and the adaptive strategies employed by flies in extreme-temperature environments. Understanding the regulating mechanisms of thermosensation and temperature preference in Drosophila can provide fundamental insights into the underlying molecular and neural mechanisms that control body temperature and temperature-related behavioral changes in other animals.

Wet age-related macular degeneration (AMD) is an end-stage event in a complex pathogenesis of macular degeneration, involving the abnormal growth of blood vessels at the retinal pigment epithelium driven by vascular endothelial growth factor (VEGF). Current therapies seek to interrupt VEGF signaling to halt the progress of neovascularization, but a significant patient population is not responsive. New treatment modalities such as integrin-binding peptides (risuteganib/Luminate/ALG-1001) are being explored to address this clinical need but these treatments necessitate the use of intravitreal injections (IVT), which carries risks of complications and restricts its availability in less-developed countries. Successful systemic delivery of peptide-based therapeutics must overcome obstacles such as degradation by proteinases in circulation and off-target binding. In this work, we present a novel dendrimer-integrin-binding peptide (D-ALG) synthesized with a noncleavable, “clickable” linker. In vitro, D-ALG protected the peptide payload from enzymatic degradation for up to 1.5 h (~90% of the compound remained intact) in a high concentration of proteinase (2 mg/mL) whereas ~90% of free ALG-1001 was degraded in the same period. Further, dendrimer conjugation preserved the antiangiogenic activity of ALG-1001 in vitro with significant reductions in endothelial vessel network formation compared to untreated controls. In vivo, direct intravitreal injections of ALG-1001 and D-ALG produced reductions in the CNV lesion area but in systemically dosed animals, only D-ALG produced significant reductions of CNV lesion area at 14 days. Imaging data suggested that the difference in efficacy may be due to more D-ALG remaining in the target area than ALG-1001 after administration. The results presented here offer a clinically relevant route for peptide therapeutics by addressing the major obstacles that these therapies face in delivery.

An almost all-digital time-to-digital converter (TDC) possessing subpicosecond resolutions, scalable dynamic ranges, high linearity, high noise immunity, and moderate conversion rates can be achieved by a random sampling-and-averaging (RSA) approach with the self-antithetic variance reduction (SAVR) technique for time-correlated single-photon counting (TCSPC) quantum measurements. This article presents detailed theoretical analysis and behavior-model verifications of the SAVR technique to effectively enhance the conversion rate of an asynchronous RSA-based TDC by more than 62 times with 7% power overhead. In addition, the proposed performance estimation methodology for SAVR can greatly improve the computation efficiency during the system-level design and reduce the read-out circuit complexity in the silicon-photonics RSA-based TCSPC realization.

Backgrounds: Epilepsy surgery is the most efficacious therapeutic modality for patients with medical refractory epilepsy, especially resective surgery. However, the variable etiologies and multiple epileptic foci are usually associated with the outcomes. The aim of this study was to demonstrate that combination of different intervention procedures might be an alternative option for patients of refractory epilepsy. Methods: We retrospectively analyzed pre-operative and post-surgical outcomes in 30 patients who received epilepsy surgery between January 1, 2010 and December 31, 2014 at Chang Gung Memorial Hospital (CGMH), Linkou, according to Engel's classification. Results: Twenty-six of the 30 patients (86.7%) had good outcomes, sum of class I and class II after epilepsy surgery. The good outcome rate of our complicated group was 80.0% (12/15), compared to 93.3% (14/15) in the simple group, but no significant differences between the two groups (p = 0.569). Four patients whose epileptic foci involved eloquent area and received multiple subpial cortical transection, and good outcome rate was 75% (3/4). At last, six patients had previously failed epilepsy surgery and received a reoperation, with a good outcome rate of 83.3% (5/6). Conclusion: After complete pre-surgical evaluation and combined interventional procedures, the patients with refractory epilepsy had satisfactory outcomes and few neurological complications. Moreover, re-operation can improve the outcome in some patients who previously failed epilepsy surgery.

Memory consolidation is a time-dependent process through which an unstable learned experience is transformed into a stable long-term memory; however, the circuit and molecular mechanisms underlying this process are poorly understood. The Drosophila mushroom body (MB) is a huge brain neuropil that plays a crucial role in olfactory memory. The MB neurons can be generally classified into three subsets: γ, αβ, and α′β′. Here, we report that water-reward long-term memory (wLTM) consolidation requires activity from α′β′-related mushroom body output neurons (MBONs) in a specific time window. wLTM consolidation requires neurotransmission in MBON-γ3β′1 during the 0–2 h period after training, and neurotransmission in MBON-α′2 is required during the 2–4 h period after training. Moreover, neurotransmission in MBON-α′1α′3 is required during the 0–4 h period after training. Intriguingly, blocking neurotransmission during consolidation or inhibiting serotonin biosynthesis in serotoninergic dorsal paired medial (DPM) neurons also disrupted the wLTM, suggesting that wLTM consolidation requires serotonin signals from DPM neurons. The GFP Reconstitution Across Synaptic Partners (GRASP) data showed the connectivity between DPM neurons and MBON-γ3β′1, MBON-α′2, and MBON-α′1α′3, and RNAi-mediated silencing of serotonin receptors in MBON-γ3β′1, MBON-α′2, or MBON-α′1α′3 disrupted wLTM. Taken together, our results suggest that serotonin released from DPM neurons modulates neuronal activity in MBON-γ3β′1, MBON-α′2, and MBON-α′1α′3 at specific time windows, which is critical for the consolidation of wLTM in Drosophila.

Long-term memory (LTM) formation depends on the conversed cAMP response element-binding protein (CREB)-dependent gene transcription followed by de novo protein synthesis. Thirsty fruit flies can be trained to associate an odor with water reward to form water-reward LTM (wLTM), which can last for over 24 hours without a significant decline. The role of de novo protein synthesis and CREB-regulated gene expression changes in neural circuits that contribute to wLTM remains unclear. Here, we show that acute inhibition of protein synthesis in the mushroom body (MB) αβ or γ neurons during memory formation using a cold-sensitive ribosome-inactivating toxin disrupts wLTM. Furthermore, adult stage-specific expression of dCREB2b in αβ or γ neurons also disrupts wLTM. The MB αβ and γ neurons can be further classified into five different neuronal subsets including αβ core, αβ surface, αβ posterior, γ main, and γ dorsal. We observed that the neurotransmission from αβ surface and γ dorsal neuron subsets is required for wLTM retrieval, whereas the αβ core, αβ posterior, and γ main are dispensable. Adult stage-specific expression of dCREB2b in αβ surface and γ dorsal neurons inhibits wLTM formation. In vivo calcium imaging revealed that αβ surface and γ dorsal neurons form wLTM traces with different dynamic properties, and these memory traces are abolished by dCREB2b expression. Our results suggest that a small population of neurons within the MB circuits support long-term storage of water-reward memory in Drosophila.

Mounting evidence indicates that the gut microbiota is linked to several physiological processes and disease development in mammals; however, the underlying mechanisms remained unexplored mostly due to the complexity of the mammalian gut microbiome. The fruit fly, Drosophila melanogaster, is a valuable animal model for studying host-gut microbiota interactions in translational aspects. The availability of powerful genetic tools and resources in Drosophila allowed the scientists to unravel the mechanisms by which the gut microbes affect fitness, health, and behavior of their hosts. Drosophila models have been extensively used not only to study animal behaviors (i.e., courtship, aggression, sleep, and learning & memory), but also some human related neurodegenerative diseases (i.e., Alzheimer’s disease and Parkinson’s disease) in the past. This review comprehensively summarizes the current understanding of the gut microbiota of Drosophila and its impact on fly behavior, physiology, and neurodegenerative diseases.

Juvenile myoclonic epilepsy (JME) is a primary generalized epilepsy which is closely related to the sleep-wake cycle. This study aimed to investigate whether sleep disturbance is more common among patients with JME and the impact this may have on their quality of life (QOL). Thirty-four patients with JME and age- and gender-matched controls were recruited into this case control study, and assessed using validated sleep questionnaires including the Epworth Sleepiness Scale (ESS), Pittsburgh Sleep Quality Index (PSQI), and Stanford Sleepiness Scale (SSS). QOL was assessed using the Quality of Life in Epilepsy Inventory (QOLIE-31). The patients had a significantly higher PSQI score and higher proportion of abnormal PSQI scores than the controls. They also had higher ESS and SSS scores, but without statistical significance. The patients with poor sleep quality had significantly lower overall QOL, emotional well-being, and energy/fatigue subscale scores. The use of a higher number of antiseizure medications, dosage of levetiracetam, and usage of antiseizure medication polytherapy were associated with sleep disorders. Our results showed that sleep disturbance is common in patients with JME, and also that it has an impact on their QOL.

Background: To analyze the efficacy and safety of perampanel over a 3-month period in a sample of Asian people with epilepsy. Methods: The efficacy and safety of perampanel as an adjunctive therapy for patients with epilepsy were retrospectively reviewed and analyzed. Patients were categorized according to seizure type, concomitant antiepileptic drug usage, and perampanel dosage. Results: A total of 210 patients were included in the study and 131 patients completed 3 months of perampanel treatment. The average dosage of perampanel was 5.31 mg/day, and the 50% responder rate (≥50% seizure frequency reduction) in all patients was 45.8%, with a 27.5% seizure-free rate. For focal seizures, focal to bilateral tonic-clonic seizures, and primary generalized seizures, the 50% responder rates were respectively 29.4%, 49.5%, and 36.4%. In total, 39.5% of patients experienced adverse events within 3 months of observation period, and the rate of drug withdrawal due to adverse events was 8.6%. Dizziness, ataxia, irritability/aggression were the most common adverse events. Conclusions: The efficacy and safety of perampanel in a real-world setting with Asian patients is comparable to that in clinical trials that have included fewer Asian patients.

Distinct subsets of dopaminergic PAM neurons have been shown to be involved in short-term and long-term memory for sugar reward. Here the authors report the neural circuits and the cellular and molecular mechanisms for short-term and long-term memory for water reward in thirstyDrosophila.

Electrical synapses between neurons, also known as gap junctions, are direct cell membrane channels between adjacent neurons. Gap junctions play a role in the synchronization of neuronal network activity; however, their involvement in cognition has not been well characterized. Three-hour olfactory associative memory in Drosophila has two components: consolidated anesthesia-resistant memory (ARM) and labile anesthesia-sensitive memory (ASM). Here, we show that knockdown of the gap junction gene innexin5 (inx5) in mushroom body (MB) neurons disrupted ARM, while leaving ASM intact. Whole-mount brain immunohistochemistry indicated that INX5 protein was preferentially expressed in the somas, calyxes, and lobes regions of the MB neurons. Adult-stage-specific knockdown of inx5 in αβ neurons disrupted ARM, suggesting a specific requirement of INX5 in αβ neurons for ARM formation. Hyperpolarization of αβ neurons during memory retrieval by expressing an engineered halorhodopsin (eNpHR) also disrupted ARM. Administration of the gap junction blocker carbenoxolone (CBX) reduced the proportion of odor responsive αβ neurons to the training odor 3 hours after training. Finally, the α-branch-specific 3-hour ARM-specific memory trace was also diminished with CBX treatment and in inx5 knockdown flies. Altogether, our results suggest INX5 gap junction channels in αβ neurons for ARM retrieval and also provide a more detailed neuronal mechanism for consolidated memory in Drosophila.

Objective: To evaluate the efficacy of abiraterone acetate in combination with prednisolone in Taiwanese men with metastatic castrate-resistant prostate cancer (mCRPC) who failed docetaxel-based chemotherapy. Materials and methods: In this single-arm, open label study, 30 mCRPC patients with prostate specific antigen (PSA) progression after docetaxel chemotherapy were enrolled. All patients were treated with abiraterone acetate 1000 mg once daily and prednisolone 5 mg twice daily. The primary end-point was PSA response rate (defined as proportion of patients achieving a PSA decline of ≥50%). Secondary end-points were overall survival and time-to-PSA progression. Results: Among 28 patients who received one or more cycles of treatment, 15 (53.6%) men achieved PSA response [95% confidence interval (CI) 33.9–72.5]. The median time-to-PSA progression was 5.5 months (95% CI 3.1–7.9). The median interval from stopping abiraterone to death was 3.4 months (95% CI 0.1–21.0), and the median overall survival was 19.2 months (95% CI 13.0–25.4). The PSA responders had better overall survival compared with PSA nonresponders, in both univariate (log rank test, p = 0.007) and multivariate (Cox regression, p = 0.001; relative risk: 0.31; 95% CI: 0.12–0.76) analysis. Both a high Gleason score (≥8) and viscera involvement did not have an unfavorable response to abiraterone treatment. Conclusion: A combination of abiraterone acetate and prednisolone can improve the overall survival in Taiwanese mCRPC patients who fail prior docetaxel chemotherapy.

Primary tubulovillous adenomas are scarcely encountered in the urinary tract, and most of these tumors arise from the intestinal segments of urinary reconstruction. We report the extremely rare case of tubulovillous adenomas primarily occurring in the urinary bladder in this article. A 50-year-old female patient initially presented with painless gross hematuria for several times within 1 month. Image studies, including abdominal ultrasonography and computed tomography, demonstrated one urinary bladder tumor with suspicious perivesical invasion. The diagnosis was made by a transurethral resection and histopathology, and no involvement of muscularis propria was confirmed. Although the pathogenesis and clinical behavior are not well understood, tubulovillous adenomas may have a tendency to undergo malignant transformation into the form of invasive adenocarcinomas. Complete resection and rigorous follow-up are strongly recommended.

The aim of this study was to examine the feasibility of ureteroscope-assisted double-J stenting following laparoscopic ureterolithotomy and to evaluate the effects of retrograde ureteroscopic access exerted on the sutured ureterotomy site. From January 2002 to December 2011, 30 patients with proximal ureteral stone underwent ureteroscopic double-J stenting of the ureter following retroperitoneal laparoscopic ureterolithotomy. Patient demographics and perioperative parameters, including the degree of hydronephrosis, urine leakage, and drainage time, were retrospectively reviewed. These data were compared with those of 30 consecutive patients who received open ureterolithotomy and intracorporeal ureteral double-J stenting. In addition, a PubMed search was conducted and the related literature on the placement of a ureteral stent was reviewed. Twenty-eight patients successfully underwent ureteral double-J stenting with ureteroscopic access. No malposition of the ureteral stent was identified in the ureteroscopic group, but two patients in the intracorporeal group required postoperative adjustment of the stent. Residual stone fragments were found during stent placement in three patients in the ureteroscopic group and holmium:yttrium–aluminum–garnet laser lithotripsy was immediately performed. There was no significant difference in postoperative outcomes or complication rates between the two groups. Ureteroscope-assisted ureteral double-J stenting is a simple and safe alternative allowing intraluminal navigation along the entire ureter, correct stent placement, and prompt treatment of residual stone fragments, without radiation exposure. In addition, ureteral disruption and urinary extravasation may not be concerns for ureteroscopic access with continuous normal saline irrigation.

In thrombolytic therapy, plasminogen activators (PAs) are still the only group of drug approved to induce thrombolysis, and therefore, critical for treatment of arterial thromboembolism, such as stroke, in the acute phase. Functionalized nanocomposites have attracted great attention in achieving target thrombolysis due to favorable characteristics associated with the size, surface properties and targeting effects. Many PA-conjugated nanocomposites have been prepared and characterized, and some of them has been demonstrated with therapeutic efficacy in animal models. To facilitate future translation, this paper reviews recent progress of this area, especially focus on how to achieve reproducible thrombolysis efficacy in vivo.

The possible neurological and biophysical effects of magnetic fields on animals is an area of active study. Here, we report that courtship activity of male Drosophila increases in a magnetic field and that this effect is regulated by the blue light-dependent photoreceptor cryptochrome (CRY). Naïve male flies exhibited significantly increased courtship activities when they were exposed to a ≥ 20-Gauss static magnetic field, compared with their behavior in the natural environment (0 Gauss). CRY-deficient flies, cryb and crym, did not show an increased courtship index in a magnetic field. RNAi-mediated knockdown of cry in cry-GAL4-positive neurons disrupted the increased male courtship activity in a magnetic field. Genetically expressing cry under the control of cry-GAL4 in the CRY-deficient flies restored the increase in male courtship index that occurred in a magnetic field. Interestingly, artificially activating cry-GAL4-expressing neurons, which include large ventral lateral neurons and small ventral lateral neurons, via expression of thermosensitive cation channel dTrpA1, also increased the male courtship index. This enhancement was abolished by the addition of the cry-GAL80 transgene. Our results highlight the phenomenon of increased male courtship activity caused by a magnetic field through CRY-dependent magnetic sensation in CRY expression neurons in Drosophila.

Astroglial glutamate transporters, GLT-1 and GLAST, play an essential role in removing released glutamate from the extracellular space and are essential for maintaining a low concentration of extracellular glutamate in the brain. It was hypothesized that impaired function of glial glutamate transporters induced by transient global ischemia may lead to an elevated level of extracellular glutamate and subsequent excitotoxic neuronal death. To test this hypothesis, in the present study, we performed whole-cell patch-clamp recording of hippocampal CA1 astrocytes in control or postischemic slices, and measured glutamate transporter activity by recording glutamate-evoked transporter currents. Six to 24 h after global ischemia, maximal amplitude of glutamate transporter currents recorded from postischemic CA1 astrocytes was significantly reduced. Western blotting analysis indicated that transient global ischemia decreased the protein level of GLT-1 in the hippocampal CA1 area without affecting GLAST protein level. Further real-time quantitative RT-PCR assays showed that global ischemia resulted in a decrease in GLT-1 mRNA level of hippocampal CA1 region. Global ischemia-induced reduction in GLT-1 expression and glutamate transporter function of CA1 astrocytes precedes the initiation of delayed neuronal death in CA1 pyramidal layer. The present study provides the evidence that transient global ischemia downregulates glutamate transporter function of hippocampal CA1 astrocytes by decreasing mRNA and protein levels of GLT-1.

To investigate the pathogenic role of connexin-32 (Cx32) mutation in X-linked dominant Charcot-Marie-Tooth disease (CMTX), dual whole-cell voltage-clamp recordings and tracer coupling were performed to investigate functional properties of wild-type and 22 CMTX mutant Cx32 proteins expressed in N2A cells. Ten mutant Cx32 proteins either formed defective junctional channels (Y65C, V95M, R107W, L156R, R164W and G199R) or failed to form gap junctions (G12S, S182T, E208K and Y211stop). Except (G12S) and (E208K) mutants, other mutant Cx32 proteins were localized in the cell membrane despite their impaired ability to form functional gap junctions. Twelve CMTX mutations (V13L, R15Q, R22Q, I30N, V35M, V63I, R75Q, Q80R, W133R, P158A, P172S and N205S) did not affect the ability of Cx32 to form homotypic gap junctions in N2A cells. Our results indicate that 10 of 22 CMTX Cx32 mutations studied in the present investigation could lead to the assembly of defective Cx32 gap junctions, which in turn may result in peripheral neuropathy. However, further studies are required to elucidate the exact mechanism by which CMTX mutant Cx32 proteins, which retain the ability to form homotypic junctional channels, damage Schwann cells and cause demyelinating neuropathy.