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Introduction: Taxus species contain the anticancer alkaloid paclitaxel, as well as other taxanes similar in structure and potentially in effect to paclitaxel. Tissue-specific distribution patterns and seasonal variations of taxanes in some Taxus species have been reported; however, it is still under-presented for the taxanes in Taxus cuspidata. Methods: The radial distributions of eight taxanes in the transverse surface of freeze-fixed T. cuspidata stems from the late summer and the spring seasons were investigated by cryo-time-of-flight secondary ion mass spectrometry and scanning electron microscopy (cryo-TOF-SIMS/SEM) visualization and liquid chromatography-mass spectrometry (LC-MS) quantitative analysis. By optical microscopic observation, seasonal differences in the amounts and distribution patterns of target taxanes were further characterized in specific tissues. Results and Discussion: The overall amount of taxanes was higher in the late summer than in the spring. Also, taxanes' radial distribution was generally found at higher concentration in the phloem, the cambium and lower level in the periderm, the latest-forming xylem, with different taxanes showing several patterns with distinction between seasons, which were considered related to seasonal plant physiological behaviors. In addition, the distribution of baccatin III (BAC) was investigated at the cellular level, which was regarded in specific cells suggesting its transport in the radial and axial directions in the T. cuspidata stem. Characterizing the microscopic distribution of taxanes in the T. cuspidata stem is expected to play a role in the further study of their biosynthesis and in planta behaviors.
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We demonstrate the 1,600-km transmission at nearly 1-Tb/s/λ signals with a capacity of 21.5 Tb/s. Probabilistic shaping was newly applied to high-speed coherent optical Nyquist pulse transmission systems to maximize the transmission capacity. Employing a 160-GBd PS-32 QAM format, WDM signals at nearly 1-Tb/s/λ were successfully transmitted over 1,600 km with a capacity of 21.5 Tb/s.
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We describe a new multiplexing technique and its application to demultiplexing in the time domain by using higher-order Hermite-Gaussian (HG) pulses, which are solutions of the Schrödinger equation. We call this technique eigen-function division multiplexing (EDM). This method enables us to further increase the total transmission capacity by superimposing many different HG pulses in the same time slot. This technique is different from a conventional optical time domain multiplexing (OTDM) technique using interleaving, where one pulse exists only in one time slot. The transmitted EDM HG pulses can be demultiplexed by adopting the time-domain orthogonality of the HG pulses (eigen-function orthogonality). The information carried by the mth-order HG pulse (HGm pulse) can be coherently detected by a photo detector, where photo-mixing with a phase-locked HGm pulse generated by a local oscillator can realize demultiplexing. The overlap integral with a different HG pulse becomes zero due to the time domain orthogonality. First, we show numerically that such a new EDM transmission scheme in the time domain is possible. We then show experimentally that we could successfully carry out an EDM HG coherent pulse transmission with four different HG pulses (HG0, HG1, HG2, and HG3), where we report a 400â¼480 Gbit/s (10 Gbaud x 4 eigen-functions x 2 pol-mux.) 32â¼64 QAM EDM transmission over 300â¼450â km.
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The goal of our study was to clarify the effect of low pulse rate fluoroscopy applying in percutaneous coronary intervention (PCI) on devices' visibility and radiation dose. Four types of fluoroscopy conditions combined with two pulse rates (7.5 and 15 pulses/s) and two types of adaptive temporal filters (ATFs) (weak and strong) were used. Samples for visibility evaluation were acquired with moving phantom and devices such as stent, balloon, and guidewire. Trailing artifacts and the visibility of stent were evaluated by Scheffe's method of paired comparisons. Incident air kerma (Ka,r) and kerma area product (PKA) in the clinic were obtained under two fluoroscopic pulse rate conditions (7.5 and 15 pulses/s). As a result, in 7.5 pulses/s fluoroscopy, trailing artifacts were decreased by using weak ATF with the median value of PKA and Ka,r reduced by about 50%, but stent visibility was decreased compared to 15 pulses/s. Therefore, a combination of 7.5 pulses/s fluoroscopy and suitable ATF can bring dose reduction with avoiding trailing artifacts, but dose per pulse should be adjusted to maintain the stent visibility.
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Intervenção Coronária Percutânea , Doses de Radiação , Fluoroscopia , Humanos , Imagens de Fantasmas , Stents , ArtefatosRESUMO
In proceeding with the advanced development of small unmanned aerial vehicles (UAVs), which are small flying machines, understanding the flight of insects is important because UAVs that use flight are attracting attention. The figure-eight trajectory of the wing tips is often observed in the flight of insects. In this study, we investigated the more efficient figure-eight motion patterns in generating lift during the hovering motion and the relationship between figure-eight motion and Reynolds number. For this purpose, we compared the ratios of the cycle-averaged lift coefficient to the power coefficient generated from each motion by varying the elevation motion angle, which is the rotational motion that represents the figure-eight motion, and the Reynolds number. The result showed that the motion with a smaller initial phase of the elevation motion angle (φe0≤90°) could generate lift more efficiently at all Reynolds numbers. In addition, the figure-eight motion was more effective when the Reynolds number was low.
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PURPOSE: The aim of this study is to assess the dynamics of the tear site of meniscal ramp lesions, particularly considering knee flexion angles, and validate anchor fixation using an all-inside device. METHODS: Eight Thiel-embalmed paired cadaveric knees with their whole bodies were used in this study. The ramp lesions were created arthroscopically, and ramp lesion dynamics were evaluated by gradually extending the knee from 90° of knee flexion. Changes in the gap and step-off (0: no step-off; 1: cross-sectional overlap exists; and 2: tibial articular surface exposed) were evaluated at 90°, 60°, 30°, and 10° of knee flexion. After dynamic evaluation, all-inside repairs of the ramp lesions using all-inside devices were conducted. Dissection was performed to confirm the position of anchor fixation. RESULTS: As the knee was extended, the gap significantly decreased at all knee flexion angles. Similarly, the step-off grade decreased as the knee was extended, and the step-off completely disappeared in all cases when the knee was extended from 30° to 10°. The average knee flexion angle at which the gap and step-off completely disappeared was 22.5°. After suturing the ramp lesion, arthroscopic evaluation showed that the gap had disappeared and the step-off had been repaired in all cases. Anchor fixation locations were not found within the joint but were fixed to the semimembranosus tendon or its surrounding articular capsule. Overall, 31% (5/16) anchors were fixed to the attachment site of the semimembranosus tendon, whereas the remaining were fixed to the articular capsule, located peripherally to the semimembranosus tendon. CONCLUSION: Suturing with an all-inside device for ramp lesions is a good option, and the repair in knee extension was found to be reasonable, considering the dynamics of ramp lesions in this study. LEVEL OF EVIDENCE: Level IV.
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Lesões do Ligamento Cruzado Anterior , Meniscos Tibiais , Humanos , Estudos Transversais , Meniscos Tibiais/cirurgia , Articulação do Joelho/cirurgia , Joelho , Cadáver , Lesões do Ligamento Cruzado Anterior/cirurgiaRESUMO
BACKGROUND: The risk of coronary artery disease in peripheral arterial disease (PAD) is high, life prognosis is poor, and lipid-lowering treatment with statins has been reported to improve prognosis. In clinical practice, however, hypolipidemia is more common in patients with severe PAD and statin prescription rates appear to be low, but specific data are scarce in Japan. Therefore, we conducted this cross-sectional study in collaboration with other centers of vascular surgery to determine the rate of statin prescriptions for PAD patients in real-world practice, the rate of achievement of low-density lipoprotein (LDL) cholesterol control targets, and whether statin non-use is a determinant factor of critical limb ischemia (CLI). METHODS: A total of 246 PAD patients (97 with CLI) from 5 sites were included in this study. Medical history and blood test data were obtained from medical records and interviews with patients, and were compared between CLI and non-CLI patients. RESULTS: Statin prescription rate was only 34â¯%. The overall LDL cholesterol control target rate was 46â¯% of CLI cases and 51â¯% of non-CLI cases, according to the lipid management criteria of the Japanese Society for Atherosclerosis 2022 guidelines. Patients in the CLI group had a lower mean body mass index and lower LDL cholesterol levels than those in the non-CLI group, suggesting that these factors were responsible for the lower statin prescription rate. However, multivariate analysis revealed that statin non-use was one of the determinants of CLI. CONCLUSIONS: Statin prescription rates for PAD patients were low in real-world practice settings in the field of vascular surgery. Since statin non-use is a determinant of CLI, there is a need to educate physicians engaged in treatment regarding lipid-lowering treatment with statins.
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Introduction: Phellodendron amurense Rupr. contains rich alkaloids, which have been extensively applied in clinical treatments for their various biological activities. However, detailed microscopic distribution and roles of such alkaloids in P. amurense stem still need to be clarified. Methods: In this study, the distribution of eight alkaloids in the transverse surface of freeze-fixed P. amurense stems in fall and summer has been visualized by cryo-time-of-flight secondary ion mass spectrometry and scanning electron microscopy (cryo-TOF-SIMS/SEM), which was found in living tissues with relative contents of different alkaloids varying with the position. In addition, the contents of these alkaloids quantified by high-performance liquid chromatography (HPLC) analysis suggested the seasonal variation from fall to the following summer. Results and discussion: Distribution of eight alkaloids in the freeze-fixed stems of P. amurense from fall and summer seasons has been visualized and assigned into specific living tissues, with relative contents varying in different positions with seasons, which suggested their possible roles in the physiological processes of the plant itself or plant responding to changes in the surrounding conditions. Conclusion: This study provided a significant basis for further discussion of the genes or enzymes involved in these processes, which will contribute to investigating biosynthetic pathways and specific in planta roles of alkaloids.
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OBJECTIVES: This study aimed to investigate whether machine learning (ML) is useful for predicting the contrast material (CM) dose required to obtain a clinically optimal contrast enhancement in hepatic dynamic computed tomography (CT). METHODS: We trained and evaluated ensemble ML regressors to predict the CM doses needed for optimal enhancement in hepatic dynamic CT using 236 patients for a training data set and 94 patients for a test data set. After the ML training, we randomly divided using the ML-based (n = 100) and the body weight (BW)-based protocols (n = 100) by the prospective trial. The BW protocol was performed using routine protocol (600 mg/kg of iodine) by the prospective trial. The CT numbers of the abdominal aorta and hepatic parenchyma, CM dose, and injection rate were compared between each protocol using the paired t test. Equivalence tests were performed with equivalent margins of 100 and 20 Hounsfield units for the aorta and liver, respectively. RESULTS: The CM dose and injection rate for the ML and BW protocols were 112.3 mL and 3.7 mL/s, and 118.0 mL and 3.9 mL/s ( P < 0.05). There were no significant differences in the CT numbers of the abdominal aorta and hepatic parenchyma between the 2 protocols ( P = 0.20 and 0.45). The 95% confidence interval for the difference in the CT number of the abdominal aorta and hepatic parenchyma between 2 protocols was within the range of predetermined equivalence margins. CONCLUSIONS: Machine learning is useful for predicting the CM dose and injection rate required to obtain the optimal clinical contrast enhancement for hepatic dynamic CT without reducing the CT number of the abdominal aorta and hepatic parenchyma.
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Meios de Contraste , Tomografia Computadorizada por Raios X , Humanos , Estudos Prospectivos , Tomografia Computadorizada por Raios X/métodos , Fígado/diagnóstico por imagem , Peso Corporal , Aorta AbdominalRESUMO
BACKGROUND: No compatibility tests are available for remdesivir other than 0.9% sodium chloride. In this study, we aimed to evaluate the physical compatibility of remdesivir with drugs used in palliative care and COVID-19 treatment. METHODS: Remdesivir was tested for compatibility with 10 different drugs (fentanyl, morphine, hydromorphone, oxycodone, heparin, furosemide, octreotide, acetated Ringer's injection, 2-in-1 peripheral parenteral nutrition, and 2-in-1 total parenteral nutrition). Remdesivir was formulated to a final concentration of 1 mg/mL, and the other drugs were prepared at clinical concentrations. Three test solutions were used for compatibility testing, with remdesivir and the target drugs compounded in a 1:1 ratio. Appearance measurements, including Tyndall effect, turbidity, and pH, were performed immediately after mixing and at 1 h and 4 h after mixing. Changes in appearance, including the Tyndall effect, turbidity (turbidity change of ≥ 0.5 nephelometric turbidity unit [NTU] based on control solution for each test drug), and pH (a change of ≥ 10% based on the pH immediately after mixing) were used to determine physical compatibility. RESULTS: All the drugs tested were compatible with remdesivir. The combination of remdesivir and furosemide produced the highest turbidity (0.23 ± 0.03 NTU) 1 h after mixing. The lowest and highest pH values were observed at 4 h after mixing for the combinations of remdesivir and morphine (3.23 ± 0.02) and remdesivir and furosemide (8.81 ± 0.06). CONCLUSIONS: The drugs tested in this study show Y-site physical compatibility with remdesivir.
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COVID-19 , Cuidados Paliativos , Humanos , Infusões Intravenosas , Tratamento Farmacológico da COVID-19 , Furosemida , Cloreto de Sódio , Derivados da MorfinaRESUMO
PURPOSE: To assess the influence of capsular tension ring (CTR) on surgical outcomes of trifocal intraocular lens (IOL) implantation in femtosecond laser-assisted cataract surgery. SETTING: Sugita Eye Clinic, Tokyo, and University of Tsukuba, Ibaraki, Japan. DESIGN: Prospective, randomized, paired-eye clinical study and laboratory study. METHODS: In the clinical study involving 44 eyes of 22 patients with no risk of zonular instability, 1 eye received IOL alone and the contralateral eye received IOL with CTR. Preoperative capsular bag diameter and postoperative IOL tilt/decentration were measured using anterior segment optical coherence tomography. In the laboratory study, IOL and CTR were implanted into an artificial capsular bag of 10 mm in diameter, and IOL centration was evaluated. RESULTS: Throughout the 12-month follow-up period, there was no significant difference in refractive and visual outcomes between groups. The amount of IOL decentration was significantly larger in eyes with CTR than in eyes without CTR at 12 months postoperatively (P = .037). There was a significant negative correlation between capsular bag diameter and the amount of IOL decentration in eyes with CTR (P = .038), but not in eyes without CTR (P = .873). The laboratory study indicated that interference between CTR eyelets and IOL haptics significantly increased IOL decentration (P < .001). CONCLUSIONS: The use of CTR did not affect refractive and visual outcomes of trifocal IOL implantation in eyes without the risk of zonular weakness. CTR coimplantation increased IOL decentration possibly due to the interference between CTR eyelets and IOL haptics.
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Cápsula do Cristalino , Lentes Intraoculares , Facoemulsificação , Humanos , Cápsula do Cristalino/cirurgia , Implante de Lente Intraocular , Facoemulsificação/métodos , Estudos Prospectivos , Resultado do TratamentoRESUMO
BACKGROUND: To investigate optimizing the use of different beam shaping filters (viz. small, medium and large) when using different tube voltages during the newborn chest computed tomography (CT) on a GE Lightspeed VCT scanner. METHODS: We used pediatric anthropomorphic phantoms with a 64 detector-row CT scanner while scanning the chest. A real-time skin dosimeter (RD - 1000; Trek Corporation, Kanagawa, Japan) was positioned into the phantom center of the body, the surface of the body back, and the right and left mammary glands. We performed and compared six scan protocols using small, medium, and large beam shaping filters at 80 and 120 kVp protocols. RESULT: There were no significant differences in the image noise for the chest scan among the different beam shaping filters. By using the large beam shaping filter at 80 kVp, it was possible to reduce the exposure dose by 5% in comparison with the small beam shaping filter, and by 10% in comparison with the medium beam shaping filter. By using the large beam shaping filter at 120 kVp, it was possible to reduce the exposure dose by 15% in comparison with the small beam shaping filter and by 20% in comparison with the medium beam shaping filter (p < 0.01). CONCLUSION: The large beam shaping filter had the most dose reduction effect during newborn chest CT on a GE Lightspeed VCT scanner. The additional copper filtration being present in the large bowtie filter of the GE Lightspeed CT scanner when using different tube voltages is more effective in reducing radiation exposure in children.
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Filtração , Tomografia Computadorizada por Raios X , Recém-Nascido , Humanos , Criança , Doses de Radiação , Tomografia Computadorizada por Raios X/métodos , Tomógrafos Computadorizados , Imagens de FantasmasRESUMO
PURPOSE: We retrospectively evaluated the visualization of pediatric coronary computed tomography angiography (CCTA) images by using the 64-detector row CT scanner between the electrocardiogram-gated helical scan and non-electrocardiogram-gated helical scan. METHODS: From January 2015 to March 2019, 100 children who underwent CT angiography examination were retrospectively enrolled. Group A consisted of 50 patients with electrocardiogram-gated helical scan. Group B consisted of 50 patients with non-electrocardiogram-gated helical scan. All patients were scanned using a 64-detector row CT scanner (LightSpeed VCT), and helical scans were acquired. The CT scanning parameters were 0.4-s rotation, 0.625-mm slice thickness, 0.24 (group A) helical pitch (beam pitch), 1.375 (group B) helical pitch (beam pitch), 80 kVp, and 50-300 mA (noise index 40). A retrospective method was used for electrocardiogram gated. To compare the radiation dose, CT volume dose index (CTDIvol) and dose length product (DLP) displayed on the console were recorded. The visualization scores of the coronary artery images were compared between each group. RESULTS: In group A, CTDIvol and DLP values were 6.74 (1.05-11.97) mGy and 79.87 (15.90-146.65) mGy·cm, respectively. In group B, CTDIvol and DLP values were 0.51 (0.39-0.95) mGy and 8.15 (6.30-17.50) mGy·cm, respectively. There were significant differences in CTDIvol and DLP values between both groups (p<0.05). The visualization rates for the proximal and distal coronary arteries were 88% and 54% for the right coronary artery, 84% and 58% for the left anterior descending artery, and 66% and 30% for the left circumflex branch in group A, respectively. The visualization rates for the proximal and distal coronary arteries were 52% and 0% for the right coronary artery, 56% and 0% for the left anterior descending artery, and 32% and 0% for the left circumflex branch in group B. CONCLUSION: In 64-row multidetector computed tomography (MDCT), the visualization rates for the proximal and distal coronary arteries were significantly higher in the electrocardiogram-gated scan, but the exposure dose was several times higher in the pediatric CCTA. For accurate diagnosis in pediatric coronary arteries, electrocardiogram-gated helical scan should be performed.
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Vasos Coronários , Tomografia Computadorizada Multidetectores , Criança , Angiografia Coronária/métodos , Vasos Coronários/diagnóstico por imagem , Humanos , Doses de Radiação , Estudos Retrospectivos , Tomógrafos ComputadorizadosRESUMO
We describe the broadband injection-locking performance of a Fabry-Perot laser diode (FP-LD) for digital coherent transmission. The dynamic locking bandwidth of the FP-LD was as wide as 28.8â GHz, which makes it possible to achieve precise carrier-phase synchronization with extremely low phase noise over a wide frequency range. By applying the FP-LD as an LO in an injection-locked homodyne receiver for digital coherent quadrature amplitude modulation (QAM) transmission, we demonstrate, for the first time, the precise demodulation of 3, 10 and 20 Gbaud 256 QAM signals even when using a widely and randomly phase-modulated transmitter laser. This is attributed to the excellent wideband dynamic injection-locking characteristics of the FP-LD.
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Processed aconite root (PA), the tuberous root of Aconitum carmichaelii prepared by autoclaving, is a crude drug used in Japanese traditional Kampo medicine and traditional Chinese medicine for the symptoms of kidney deficiency, that is related to the muscle atrophy in modern medicine. The objective of the present study is to evaluate the effectiveness of PA on muscle atrophy and to find its active ingredients using dexamethasone-induced muscle ring finger protein-1 (MuRF1) mRNA expression in murine myoblast C2C12 cells. Dexamethasone-induced MuRF1 expression was significantly suppressed by methanol-soluble part of boiling water extract of PA in a concentration-dependent manner with its IC50 value of 1.5 mg/ml. By the activity-guided fractionations of PA extract using the partition between organic solvents and its aqueous solution, the activity of PA did not transfer into the fraction containing aconitine-type diterpenoid alkaloids but into BuOH layer. Then, we found higenamine and salsolinol as the active ingredients in PA. Higenamine and salsolinol significantly suppressed dexamethasone-induced MuRF1 expression, and their IC50 values were 0.49 and 50 µM, respectively. The contents of higenamine and salsolinol in the decoctions of commercially available fourteen PA products are 0.12 and 14 µg/ml as the average values, and varied with the coefficient of variation (CV) values of 97 and 63%, respectively. Higenamine also significantly suppressed dexamethasone-induced mRNA expressions of muscle atrophy F-box protein (MAFbx)/atrogin1, casitas B-lineage lymphoma-b (Cbl-b), troponin, branched-chain amino acid aminotransferase 2 (BCAT2), and Bcl-2 binding and pro-apoptotic protein3 (Bnip3). Although the quality control of PA is regulated by the contents of diterpene alkaloids, salsolinol and higenamine can be used as the marker compounds to certificate the pharmacological activities of PA.
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Aconitum , Aconitum/química , Animais , Dexametasona/efeitos adversos , Camundongos , Músculos/metabolismo , Atrofia Muscular/induzido quimicamente , Atrofia Muscular/tratamento farmacológico , RNA MensageiroRESUMO
To investigate the biosynthetic pathways and regulatory mechanisms of lignans in plants, the actual distributions of lignans and lignan glucosides in flash-frozen stems of Ginkgo biloba L. (Ginkgoaceae) were studied using cryo time-of-flight secondary ion mass spectrometry coupled with scanning electron microscopy (cryo-TOF-SIMS/SEM). Four lignans and four lignan glucosides were successfully characterized. Quantitative HPLC measurements were conducted on serial tangential sections of freeze-fixed ginkgo stem to determine the amount and approximate distribution of lignan and lignan glucosides. (-)-Olivil 4,4'-di-O-ß-d-glucopyranoside (olivil DG) was the most abundant lignan glucoside in ginkgo and was distributed mainly in the phloem, ray parenchyma cells, and pith. The comparative accumulation of olivil DG revealed its possible transport pathways and storage sites in ginkgo. Although not all relevant enzymes have been identified, understanding the distributions of lignan and lignan glucosides in ginkgo stems provides significant insight into their biological functions.
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Ginkgo biloba , Lignanas , Cromatografia Líquida de Alta Pressão , Ginkgo biloba/química , Glucosídeos/química , Lignanas/química , SementesRESUMO
Sarcopenia is an age-related loss of skeletal muscle associated with adverse outcomes such as falls, fractures, disability, and increased mortality in older people and hospitalized patients. About half of older male nursing home residents have sarcopenia. The diagnostic criteria by the European Working Group on Sarcopenia in Older People (EWGSOP) and the Asian Working Group for Sarcopenia (AWGS) have led to increased interest in sarcopenia. Exercise and nutritional management are crucial for the prevention and treatment of sarcopenia. Nutritional therapy for sarcopenia that includes 20 g of whey protein and 800 IU of vitamin D twice a day improves lower limb strength. Exercise therapy for sarcopenia, such as resistance training and 6 months of home exercises, improves muscle strength and physical function. Combination therapy that includes both nutritional and exercise therapy improves gait speed and knee extension strength more than either exercise alone or nutrition therapy alone. Excessive bedrest and mismanagement of nutrition in medical facilities can lead to iatrogenic sarcopenia. Iatrogenic sarcopenia is sarcopenia caused by the activities of health care workers in health care facilities. Appropriate nutritional management and exercise programs through rehabilitation nutrition are important for prevention and treatment of iatrogenic sarcopenia. Nutritional and exercise therapy should be started very early after admission and adjusted to the level of inflammation and disease status. Repeated assessment, diagnosis, goal setting, interventions, and monitoring using the rehabilitation nutrition care process is important to maximize treatment effectiveness and improve patients' functional recovery and quality of life.
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We describe experimental and numerical results regarding the influence of chromatic dispersion in optical fibers on guided acoustic-wave Brillouin scattering (GAWBS) phase noise compensation with a pilot tone (PT). We compared the compensation performance for GAWBS phase noise generated in an ultra-large-area fiber (ULAF) where DULAF = 21 ps/nm/km with that in a dispersion-shifted fiber (DSF) where DDSF = -1.3 ps/nm/km and found that the performance depends strongly on chromatic dispersion. The numerical analysis shows that the group delay between the signal and PT caused by chromatic dispersion reduces the GAWBS noise correlation between them, which degrades the compensation performance for GAWBS phase noise. It is clarified that a condition for effective GAWBS compensation is that the group delay between the signal and PT should be less than half the period of the GAWBS phase noise component.
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We propose the precise and wideband compensation of the nonlinear phase noise caused by cross-phase modulation (XPM) among WDM channels using a pilot tone (PT) and injection locking for short-reach, higher-order QAM transmission. A high spectral efficiency is maintained by sharing a single PT among multiple channels. We describe a 60 ch, 3 Gbaud PDM-256 QAM transmission over 160 km, where the bit error rate was improved from 6 × 10-3 to 2 × 10-3 by employing the proposed XPM compensation technique, with a spectral efficiency of 10.3 bit/s/Hz. We also analyze the influence of the group delay caused by fiber chromatic dispersion that determines the compensation range achievable with a single PT. We obtained good agreement with the experimental results.