Breast milk concentrations of acetaminophen and diclofenac - unexpectedly high mammary transfer of the general-purpose drug acetaminophen.

BACKGROUND: Breastfeeding is considered to be the most effective way of ensuring the health and survival of newborns. However, mammary transfer of drugs administered to mothers to breastfeeding infants remains a pressing concern. Acetaminophen and diclofenac sodium are widely prescribed analgesics for postpartum pain relief, but there have been few recent reports on the mammary transfer of these drugs, despite advances in analytic techniques. METHODS: We conducted a study on 20 postpartum mothers from August 2019-March 2020. Blood and milk samples from participants were analyzed using liquid chromatography-electrospray ionization tandem mass spectrometry within 24 hours after oral administration of acetaminophen and diclofenac sodium. The area under the concentration-time curve (AUC) was calculated from the concentration curve obtained by a naive pooled-data approach. RESULTS: For acetaminophen, AUC was 36,053 ng/mL.h and 37,768 ng/mL.h in plasma and breast milk, respectively, with a milk-to-plasma drug concentration ratio of 1.048. For diclofenac, the AUC was 0.227 ng/mL.h and 0.021 ng/mL.h, in plasma and breast milk, respectively, with a milk-to-plasma drug concentration ratio of 0.093. CONCLUSIONS: While diclofenac sodium showed low mammary transfer, acetaminophen showed a relatively high milk-to-plasma drug concentration ratio. Given recent studies suggesting potential connections between acetaminophen use during pregnancy and risks to developmental prognosis in children, we believe that adequate information regarding the fact that acetaminophen is easily transferred to breast milk should be provided to mothers.

Mechanical Thrombectomy for Acute Cardiogenic Internal Carotid Artery Occlusion with Cross-Flow through the Communicating Artery.

AIM: To report mechanical thrombectomy (MT) for internal carotid artery (ICA) occlusion with cross-flow through the communicating artery ("with" group), and to compare it with ICA or middle cerebral artery occlusion without cross-flow ("without" group). MATERIAL AND METHODS: This study included 10 and 57 cases of the "with" and "without" groups, respectively. Cases analyzed by rapid processing of perfusion and diffusion (RAPID) since October 2020 were included. RESULTS: Puncture-to-reperfusion time was 78.5 and 39 min (p=0.0155), the National Institutes of Health Stroke Scale score at discharge was 10.5 and 4 (p=0.0166), decline from pre to post Diffusion-Weighted Image-Alberta Stroke Program Early computed tomography (CT) Score was 0.5 and 0 (p=0.0495), and the modified Rankin Scale score at 90 days was 4 and 2 (p=0.0195) in the "with" and "without" groups, respectively. Furthermore, Tmax values of > 6 s (50 cc vs. 164 cc; p=0.0277) and Tmax > 4 s/Tmax > 6 s ratio (3.23 vs. 1.55) (p=0.0074) were significantly different between the "with" and "without" groups. CONCLUSION: The "with" group may have been affected by the longer treatment time and being at high risk of distal migration of thrombus due to poor prognosis. Although the region with a Tmax of > 6 s tends to be small in patients of the "with" group, it indicates a low-perfusion state that can lead to cerebral infarction, and MT should be performed.

Ultrafast pump-probe spectroscopy via chirped-pulse up-conversion with dispersion compensation.

In this study, ultrafast transient signals were detected on a single-shot basis using chirped-pulse up-conversion spectroscopy with dispersion compensation. Unlike in the conventional time-encoding technique using chirped pulses, distortion of the ultrafast waveform was reduced by applying dispersion compensation to the chirped probe pulses and using sum-frequency generation with the chirped readout pulses. The method was applied to terahertz time-domain spectroscopy and near-infrared pump-probe spectroscopy, providing ultrafast observations with an improved temporal resolution comparable to the transform-limited pulse durations. Terahertz waveforms, Kerr rotation signals, and phonon-polariton oscillations were measured accurately with no significant waveform distortion, thereby showing the proposed scheme to be promising for single-shot pump-probe spectroscopy in a wide range of spectroscopic applications.

Surgical outcomes of intraoperative O-arm versus C-arm fluoroscopy in occipitocervical fixation: a retrospective analysis.

PURPOSE: This study aims to compare the effect of using O-arm and C-arm fluoroscopy on the surgical outcomes of occipitocervical fixation. METHODS: The study included patients who underwent occipitocervical fixation using O-arm or C-arm between 2005 and 2021. Of 56 patients, 34 underwent O-arm-assisted surgery (O-group) and 22 underwent C-arm-assisted surgery (C-group). We assessed surgical outcomes, including operative time, intraoperative blood loss, perioperative complications, and bone union. RESULTS: Almost half of the patients had rheumatoid arthritis-related disorders in both groups. Sixteen cases (47.1%) in the O-group and 12 cases (54.5%) in the C-group were fixed from occipito (Oc) to C3, 12 cases (38.2%) in the O-group and 7 cases (31.8%) in the C-group from Oc to C4-7, 5 cases (14.7%) in the O-group, and 3 cases (13.6%) in the C-group from Oc to T2 (p = 0.929). There was no significant difference in operative time (p = 0.239) and intraoperative blood loss (p = 0.595) between the two groups. Dysphagia was the most common complication in both groups (O-group vs. C-group, 11.7% vs. 9.1%). Regarding implant-related complications, occipital plate dislodgement was observed in four cases (18.2%) in the C-group (p = 0.02). The bone union rate was 96.3% in the O-group and 93.3% in the C-group (P = 1). CONCLUSIONS: O-arm use is associated with a reduced rate of occipital plate dislodgment and has a similar complication incidence compared with C-arm-assisted surgery and does not prolong operative time despite the time needed for setting and scanning. Accordingly, an O-arm is safe and useful for occipitocervical fixation surgery.

Reliability and head-loading effects in imaging diagnosis of vertical subluxation in patients with rheumatoid arthritis.

OBJECTIVES: The purpose of this study was to examine the reproducibility of vertical subluxation parameters using X-ray, computed tomography and tomosynthesis while comparing the head-loading effects. METHODS: The vertical subluxation parameters of 26 patients (retrospective review) were evaluated. Using the intra-class correlation coefficient, we statistically examined the intra-rater and inter-rater reliabilities of the parameters. Head-loaded and -unloaded imagings were compared using a Wilcoxon signed-rank test. RESULTS: The intra-rater reliability of tomosynthesis and computed tomography showed intra-class correlation coefficients of ≥0.8 (X-ray range: 0.6-0.8), with similar results for the inter-rater reliabilities. Further, in the head-loading imaging, the tomosynthesis had significantly higher vertical subluxation scores than computed tomography (P < 0.05). CONCLUSIONS: In comparison with the X-ray, tomosynthesis and computed tomography were more accurate and reproducible. In terms of head loading, the vertical subluxation values for tomosynthesis were worse than those for computed tomography, indicating that tomosynthesis was more effective than computed tomography in diagnosing vertical subluxation.

Pulse-to-pulse detection of terahertz radiation emitted from the femtosecond laser ablation process.

Determining the dynamics of electrons and ions emitted from a target material during laser ablation is crucial for desirable control of laser processing. However, these dynamics are still challenging to understand because of a lack of ubiquitous spectroscopic tools to observe tangled-up dynamics appearing at ultrafast timescales. Here by harnessing highly sensitive single-shot terahertz time-domain spectroscopy using an echelon mirror, we investigate pulse-to-pulse temporal profile of terahertz radiation generated from the material surface. We clearly found that the carrier-envelope phase and the electric field amplitude of the terahertz waveform systematically vary between the pre- and post-ablation depending on the laser fluence and irradiated pulse numbers. Our results provide a stepping-stone towards perception of Coulomb explosion occurring throughout the laser ablation process, which is indispensable for future laser processing applications.

Postoperative Complications and Survival Rate in Hemodialysis-Dependent Patients Undergoing Cervical Spine Surgery.

Introduction: Spine surgery is challenging in hemodialysis (HD)-dependent patients owing to their poor general condition. However, postoperative complications and the mortality and survival rates have not been specifically evaluated in a wide series. This study aimed to elucidate postoperative complications and the survival rate in cervical spine surgery in HD patients. Methods: This study included 109 HD patients (70 men, 39 women) who had undergone cervical spine surgery between July 1996 and May 2018. Based on radiological diagnosis, we divided them into the destructive spondyloarthropathy (DSA) and non-DSA groups. We investigated the causes of hemodialysis, postoperative complications, postoperative inpatient mortality rate, and survival rate. Results: The DSA and non-DSA groups included 100 surgeries in 89 patients and 21 surgeries in 20 patients, respectively. The mean age at surgery was 62.9 years for the DSA and 55.9 years for the non-DSA group (P=0.97). The DSA group had a shorter hemodialysis period at surgery compared with the non-DSA group (21.7 vs. 26.5 years, P<0.05). The two most common causes of HD in both groups were chronic glomerulonephritis (DSA, 45%; non-DSA, 57.1%) and diabetes (DSA, 11%; non-DSA, 14.5%). Postoperative complications were observed in 23% (23/100) and 19% (4/21) of surgeries in the DSA and non-DSA groups, respectively (P=0.782). The total in-hospital mortality rate was 2.5% (3/121). The 1-, 3-, 5-, and 10-year postoperative survival rates of all patients were 89.6%, 75.5%, 67.1%, and 44.7%, respectively. The survival rates did not depend on the group (DSA vs. non-DSA), pre- and postoperative Japanese Orthopedic Association score for cervical myelopathy, hemodialysis period, sex, and age (P>0.05). However, significantly low survival rates were observed in HD caused by diabetes compared with that by chronic glomerulonephritis (P<0.001) and other causes (P<0.001). Conclusions: Cervical spine surgery in HD patients is associated with postoperative complications. The postoperative survival rate was found to be low if the cause of hemodialysis was diabetes.

O-Arm Assisted Cervicothoracic Spine Pedicle Screw Placement Accuracy Is Higher Than C-Arm Fluoroscopy.

OBJECTIVE: We compared the accuracy of C-arm fluoroscopy versus O-arm-assisted pedicle screw (PS) placement in the cervicothoracic spinal junction (CTSJ). METHODS: Patients who underwent PS placement in the CTSJ (C7-T4) at our hospital were included in this study. Of 37 patients who underwent PS placement in the CTSJ, 20 underwent intraoperative C-arm fluoroscopy-assisted surgery (C Group) and 17 underwent intraoperative O-arm-assisted surgery (O Group). In total, 159 PSs were placed-73 in the C Group and 86 in the O Group. The accuracy of PS placement was compared between the C Group and O Group using the classification proposed by Gertzbein and Robbins to analyze pedicle violation. RESULTS: PS accuracy was higher in the O Group than C Group; PS placement evaluated as grade A, representing no perforation, was 95.3% (82/86) for the O Group, whereas it was 78.1% (57/73) for the C Group. There was a clear statistically significant difference in accuracy of PS placement between the groups (P = 0.0013). CONCLUSIONS: O-arm-assisted surgery improved the accuracy of PS placement in the CTSJ.

An Older Thrombus Delays Reperfusion after Mechanical Thrombectomy for Ischemic Stroke.

BACKGROUND: Thrombosis is a dynamic process, and a thrombus undergoes physical and biochemical changes that may alter its response to reperfusion therapy. This study assessed whether thrombus age influenced reperfusion quality and outcomes after mechanical thrombectomy for cerebral embolism. METHODS: We retrospectively evaluated 185 stroke patients and thrombi that were collected during mechanical thrombectomy at three stroke centers. Thrombi were pathologically classified as fresh or older based on their granulocytes' nuclear morphology and organization. Thrombus components were quantified, and the extent of NETosis (the process of neutrophil extracellular trap formation) was assessed using the density of citrullinated histone H3-positive cells. Baseline patient characteristics, thrombus features, endovascular procedures, and functional outcomes were compared according to thrombus age. RESULTS: Fresh thrombi were acquired from 43 patients, and older thrombi were acquired from 142 patients. Older thrombi had a lower erythrocyte content (p < 0.001) and higher extent of NETosis (p = 0.006). Restricted mean survival time analysis revealed that older thrombi were associated with longer puncture-to-reperfusion times (difference: 15.6 minutes longer for older thrombi, p = 0.002). This association remained significant even after adjustment for erythrocyte content and the extent of NETosis (adjusted difference: 10.8 minutes, 95% confidence interval [CI]: 0.6-21.1 minutes, p = 0.039). Compared with fresh thrombi, older thrombi required more device passes before reperfusion (p < 0.001) and were associated with poorer functional outcomes (adjusted common odds ratio: 0.49; 95% CI: 0.24-0.99). CONCLUSION: An older thrombus delays reperfusion after mechanical thrombectomy for ischemic stroke. Adding therapies targeting thrombus maturation may improve the efficacy of mechanical thrombectomy.

Temperature Dependence of Carrier Extraction Processes in GaSb/AlGaAs Quantum Nanostructure Intermediate-Band Solar Cells.

From the viewpoint of band engineering, the use of GaSb quantum nanostructures is expected to lead to highly efficient intermediate-band solar cells (IBSCs). In IBSCs, current generation via two-step optical excitations through the intermediate band is the key to the operating principle. This mechanism requires the formation of a strong quantum confinement structure. Therefore, we focused on the material system with GaSb quantum nanostructures embedded in AlGaAs layers. However, studies involving crystal growth of GaSb quantum nanostructures on AlGaAs layers have rarely been reported. In our work, we fabricated GaSb quantum dots (QDs) and quantum rings (QRs) on AlGaAs layers via molecular-beam epitaxy. Using the Stranski-Krastanov growth mode, we demonstrated that lens-shaped GaSb QDs can be fabricated on AlGaAs layers. In addition, atomic force microscopy measurements revealed that GaSb QDs could be changed to QRs under irradiation with an As molecular beam even when they were deposited onto AlGaAs layers. We also investigated the suitability of GaSb/AlGaAs QDSCs and QRSCs for use in IBSCs by evaluating the temperature characteristics of their external quantum efficiency. For the GaSb/AlGaAs material system, the QDSC was found to have slightly better two-step optical excitation temperature characteristics than the QRSC.

Surgical Technique and Accuracy of S2 Alar-Iliac Screw Insertion Using Intraoperative O-Arm Navigation: An Analysis of 120 Screws.

OBJECTIVE: To evaluate the surgical technique and accuracy of S2 alar-iliac (SAI) screw placement using intraoperative O-arm-based 3-dimensional navigation (O-arm). METHODS: This study involved 60 patients who underwent SAI screw placement using the O-arm system between September 2013 and September 2019. These surgeries were performed by 5 different surgeons. For O-arm-based SAI screw insertion, a reference frame was attached to the spinous process of the lower lumbar spine (usually L4) so as not to interfere with SAI screw insertion and to facilitate simultaneous L5-S posterior interbody fusion with navigation. The navigated probe, iliac tap, and screwdriver were used for SAI screw insertion. Screw placement accuracy and screw length were assessed using postoperative computed tomography. Perioperative complications were also evaluated. RESULTS: Mean age at surgery was 68.1 (range, 30-83) years. In total, 120 screws were inserted. Rate of accurate screw placement was 98.3% (118/120 screws). The 2 misplaced screws breached the anterior cortex of the sacrum. Mean screw length was 85.6 (range, 70-90) mm. There were no significant neurovascular or visceral complications perioperatively. CONCLUSIONS: SAI screw placement can be safely performed using the intraoperative O-arm system and our surgical technique.

Comparison of Atlantoaxial Fusion with Transarticular Screws and C1 Lateral Mass-C2 Screws Using Intraoperative O-Arm Navigation.

OBJECTIVE: This study compared the surgical outcomes of atlantoaxial fusion with transarticular screws (TASs) and C1 lateral mass-C2 screws (screw-rod constructs [SRCs]) using the intraoperative O-arm navigation system (O-arm). METHODS: Among a total of 28 patients who underwent atlantoaxial fixation, 13 underwent TAS fixation and 15 underwent SRC fixation using the O-arm. All patients underwent Brooks procedure with iliac bone graft in addition to screw fixation. TAS fixation was performed for cases without high-riding vertebral artery (hVA). In the SRC group, pars or lamina screws were inserted for the side with a C2 hVA. Operative time, intraoperative bleeding, perioperative complications, screw accuracy, and bone union were evaluated. RESULTS: There were statistically significant differences in mean operative time between the 2 procedures (166 minutes in the TAS group vs. 212 minutes in the SRC group, P < 0.05) and in mean blood loss (80 vs. 185 mL, respectively; P < 0.01). Two patients developed temporary postoperative occipital neuralgia probably related to C2 nerve root in the SRC group. No screws violated the cortex in either group. Complete bone union was observed in all cases. CONCLUSIONS: O-arm-assisted TAS fixation had less intraoperative blood loss, shorter operative time, and fewer screw insertion complications than O-arm-assisted SRC fixation. O-arm-assisted TAS fixation is preferable for atlantoaxial fusion in patients without hVA.

Communicating Syringomyelia.

BACKGROUND: Communicating syringomyelia can develop in association with hydrocephalus, with communication between syringomyelia and the fourth ventricle a representative neuroimaging finding. CASE DESCRIPTION: A 51-year-old woman presented with slowly progressive bladder dysfunction and scoliosis. She had a nonfunctioning cerebrospinal fluid shunt that had been placed after birth for neonatal hydrocephalus. Tetraventricular enlargement and a holocord syrinx were noted in neuroimaging findings, while phase contrast magnetic resonance imaging and ventriculography revealed communication between the syrinx and fourth ventricle via a dilated central canal. Placement of a de novo ventriculoperitoneal shunt led to collapse of the syringomyelia, though apparent improvement of clinical symptoms was not obtained. CONCLUSIONS: Communicating syringomyelia can develop as a late complication in patients with shunted hydrocephalus. In the majority of reported cases, shunt revision has been shown to be effective, though some cases require posterior fossa decompression and exploration.

Cervical Pedicle Screw Insertion Using O-Arm-Based 3D Navigation: Technical Advancement to Improve Accuracy of Screws.

OBJECTIVE: This study aimed to report the technical advancement to improve the accuracy of cervical pedicle screw (CPS) placement using O-arm-based 3D navigation. METHODS: Sixty-four patients who underwent CPS using O-arm in the spine level of C2 to C7 between June 2013 and February 2020 were involved. In the first phase, a reference frame was placed onto the spinous process of the cranial vertebrae and used it at a maximum of 3 vertebral levels. The navigation guide sleeve was used to drill a screw hole. In the second phase, a reference frame that can hold 3 vertebrae was introduced. In the third phase, a drill guide sleeve to minimize bending of the drill tip was developed. In the fourth phase, navigated surgical drill was introduced. Screw accuracy was assessed using Neo classification: grade (G) 0, no perforation; G1, perforation <2 mm; G2, perforation 2-4 mm; and G3, perforation >4 mm. RESULTS: Mean age at surgery was 67 (19-88) years. A total of 317 CPSs were inserted. In total, 83 screws were inserted in the first phase, 60 in the second phase, 87 in the third phase, and 87 in the fourth phase. The total proportion of malpositioning was 3.8% (12/317 screws) and all were G1; 6.0% (5/83 screws) in the first phase, 8.3% (5/60 screws) in the second phase, 1.2% (1/87 screws) in the third phase, and 1.2% (1/87 screws) in the fourth phase (P < 0.05). CONCLUSIONS: O-arm use improved CPS placement accuracy with the advancement of techniques and instruments.

Surgical Results of Intraoperative C-arm Fluoroscopy Versus O-arm in Transarticular Screw Fixation for Atlantoaxial Instability.

OBJECTIVE: This study compared the surgical results of transarticular screw (TAS) fixation for atlantoaxial instability between C-arm fluoroscopy and O-arm. METHODS: Of 58 patients who underwent TAS fixation for atlantoaxial instability, 35 underwent C-arm-assisted surgery (C-group) and 23 underwent O-arm-assisted surgery (O-group). In total, 78 TASs were placed: 39 in the C-group and 39 in the O-group. Unilateral and bilateral TAS fixation was performed in 38 and 20 patients, respectively. All patients underwent Brook's procedure with TAS. TAS fixation accuracy on postoperative computed tomography, operative time, intraoperative bleeding, perioperative complications, and bone union were evaluated. Screw accuracy was assessed using Neo's classification: grade (G) 0, no perforation; G1, perforation <2 mm; G2, perforation 2-4 mm; G3, perforation >4 mm. RESULTS: TAS fixation accuracy was greater in the O-group than the C-group: G0: 38, 97.4%; G1: 1, 2.6% (O-group) vs G0: 22, 56.4%; G1: 11, 28.2%; G2: 3, 7.7%; G3: 3, 7.7% (C-group) (P < 0.001). Median operative time and median blood loss were similar between both groups. Bone union rate was greater with bilateral than unilateral TAS fixation (P < 0.05). There were no complications regarding screw malposition. Deep wound infection was observed in 1 case in the C-group. CONCLUSIONS: O-arm use improved TAS fixation accuracy. Blood loss was equivalent between the groups. O-arm-assisted TAS fixation did not prolong operative time despite the time required for setting and scanning. The O-arm is safe and useful for TAS fixation in atlantoaxial instability.

Incidence of Remote Cerebellar Hemorrhage in Patients with a Dural Tear during Spinal Surgery: A Retrospective Observational Analysis.

INTRODUCTION: The incidence of remote cerebellar hemorrhage (RCH) in patients with a dural tear during spinal surgery is unclear. The purpose of this study was to determine the incidence of RCH and the causative factors in these patients. METHODS: Two hundred and thirty-nine patients underwent spinal surgery at our institution between March 2015 and September 2016. Eleven of these patients needed dural suturing intraoperatively. All patients underwent CT of the head on the first postoperative day and were categorized according to whether they had RCH or not. The mean values for the amount of intraoperative bleeding, maximum perioperative blood pressure, postoperative drainage volume, and complaints of headache during the first 24 h postoperatively were compared between the two groups using the Welch's two-sample t-test and Fisher's exact test. The follow-up duration was 12 months. RESULTS: There were four patients in the RCH group and seven in the non-RCH group. The incidence of RCH was 36.4%. There were three cerebellar hemorrhages and one interhemispheric fissure hemorrhage in the RCH group. The mean intraoperative bleeding volume was 284 mL in the RCH group and 569 mL in the non-RCH group. The mean respective values for maximum perioperative blood pressure and postoperative drainage volume were 132 mmHg and 547 mL in the RCH group and 144 mmHg and 567 mL in the non-RCH group; none of the differences was statistically significant. However, complaints of headache in the first 24 h postoperatively were significantly more common in the RCH group than in the non-RCH group (100% vs. 14.3%; p = 0.01). All patients with intracranial bleeding had recovered 3 months after surgery. CONCLUSIONS: The incidence of RCH following a dural tear during spinal surgery was 36.4%. There was a significant association between RCH and increased reporting of headache during the first 24 h postoperatively.

Solution-processed intermediate-band solar cells with lead sulfide quantum dots and lead halide perovskites.

The intermediate-band solar cell (IBSC) with quantum dots and a bulk semiconductor matrix has potential for high power conversion efficiency, exceeding the Shockley-Queisser limit. However, the IBSCs reported to date have been fabricated only by dry process and their efficiencies are limited, because their photo-absorption layers have low particle density of quantum dots, defects due to lattice strain, and low bandgap energy of bulk semiconductors. Here we present solution-processed IBSCs containing photo-absorption layers where lead sulfide quantum dots are densely dispersed in methylammonium lead bromide perovskite matrices with a high bandgap energy of 2.3 eV under undistorted conditions. We confirm that the present IBSCs exhibit two-step photon absorption via intermediate-band at room temperature by inter-subband photocurrent spectroscopy.

Material challenges for solar cells in the twenty-first century: directions in emerging technologies.

Photovoltaic generation has stepped up within the last decade from outsider status to one of the important contributors of the ongoing energy transition, with about 1.7% of world electricity provided by solar cells. Progress in materials and production processes has played an important part in this development. Yet, there are many challenges before photovoltaics could provide clean, abundant, and cheap energy. Here, we review this research direction, with a focus on the results obtained within a Japan-French cooperation program, NextPV, working on promising solar cell technologies. The cooperation was focused on efficient photovoltaic devices, such as multijunction, ultrathin, intermediate band, and hot-carrier solar cells, and on printable solar cell materials such as colloidal quantum dots.