Analysis of volatile organic compounds and potential odour compounds in food contact paperboard using headspace two-dimensional GC-QTOF-MS

The objective was to establish a robust and reliable approach for the characterisation of volatile organic compounds (VOCs) present in food contact paperboard. This was achieved through the utilisation of headspace solid-phase microextraction in tandem with comprehensive two-dimensional (2D) gas chromatography (GC) and quadrupole time-of-flight mass spectrometry (HS-SPME-GC × GC-QTOF-MS). The experimental parameters were optimised, involving the use of a DVB/C-WR/PDMS fibre at a temperature of 80 °C for a duration of 30 min. A total of 344 VOCs comprising aldehydes, ketones, alcohols, ethers, esters, alkanes and aromatic compounds, were tentatively identified in the samples. Twelve compounds believed to be from biogenic sources had a high odour impact making them major contributors to potential taint from the paperboard samples. Significant attention should be devoted to five compounds namely, 2-methylnaphthalene, 2-pentyl-furan, furfural, 1-octen-3-one and 1-octen-3-ol due to their potential adverse impact on the organoleptic qualities of packaged food items and their potential toxicity.Abbreviations: C-WR: carbon wide range; DVB: divinylbenzene; GC-MS: gas chromatography - mass spectrometry; GCxGC-QTOF-MS: comprehensive two-dimensional gas chromatography coupled to quadrupole-time-of-flight - mass spectrometry; HS-SPME: headspace - solid phase microextraction; LOD: limit of detection; LOQ: limit of quantification; OAV: odor activity values; PDMS: polydimethylsiloxane; RI: retention index; TTC: threshold of toxicological concern; VOC: volatile organic compound.

[Early efficacy of three dimensional printed anatomical biomimetic cervical artificial disc replacement in the treatment of cervical degenerative diseases]

Objective: To investigate the efficacy and safety of a new cervical artificial disc prosthesis in the treatment of cervical degenerative diseases. Methods: The clinical data of 18 patients with single-level cervical degenerative diseases who underwent three dimensional printed anatomical bionic cervical disc replacement at Department of Spinal Surgery,Honghui Hospital,Xi'an Jiaotong University from May 2019 to July 2020 were analyzed retrospectively. There were 7 males and 11 females,aged (45±8) years old(range:28 to 58 years).The surgical segment was located at C_3－4 level in 2 cases, C_4－5 level in 5 cases, C_5－6 level in 9 cases, and C_6－7 level in 2 cases.The clinical and radiographic outcomes were recorded and compared at preoperative,postoperative times of one month and twelve months.The clinical assessments contained Japanese orthopedic association (JOA) score,neck disability index (NDI) and visual analogue scale (VAS).Imaging assessments included range of motion (ROM) of cervical spine, prosthesis subsidence and prosthesis anteroposterior migration.Repeated measurement variance analysis was used for comparison between groups,and paired t test was used for pairwise comparison. Results: All patients underwent the operation successfully and were followed up for more than 12 months.Compared with preoperative score,the JOA score,NDI and VAS were significantly improved after surgery (all P<0.01).There was no significant difference in postoperative ROM compared with 1-and 12-month preoperative ROM (t=1.570,P=0.135;t=1.744,P=0.099). The prosthesis subsidence was (0.29±0.13) mm (range: 0.18 to 0.50 mm) at 12-month postoperatively.The migration of prosthesis at 12-months postoperatively were (0.71±0.20) mm (range: 0.44 to 1.08 mm).There was no prosthesis subsidence or migration>2 mm at 12-month postoperatively. Conclusion: Three dimensional printed anatomical biomimetic cervical artificial disc replacement has a good early clinical effect in the treatment of cervical degenerative diseases, good mobility can be obtained while maintaining stability.

[Dynamic visual analysis of neutrophils chemotaxis in peritoneal cavity of schizophrenic model in mice]

OBJECTIVE

To compare the differences of neutrophils chemotaxis ability in peritoneal cavity between normal rats and schizopherenic rats with cell dynamic visualization system.

METHODS

In the study,18 healthy Kunming rats were randomly divided into 3 groups which were control group (n=6), 0.3 mg/kg MK-801 treatment group (n=6), 0.6 mg/kg dizocilpine maleate (MK-801) treatment group(n=6), extracted neutrophils separately, and observed the morphology and counted under a microscope. Each group of cells was divided into two parts for chemotactic experiment, called chemokine agent treatment group and no chemokine agent treatment group respectively, indicating control 1, 0.3 mg/kg MK-801 treatment 1,0.6 mg/kg MK-801 treatment 1 and control 2, 0.3 mg/kg MK-801 treatment 2,0.6 mg/kg MK-801 treatment 2. The dynamic migration of cells was recorded using the NIS-Elements software, and TAXIScan Analyzer 2 software was used to select 30 cells (n=30) in each group of cells and analyze cells migration trajectory, speed and distance, and use pair test and One-Way analysis of variance for statistical analysis.

RESULTS

The number of neutrophils in control group, 0.3 mg/kg MK-801 treatment group and 0.6 mg/kg MK-801 treatment group were(1.00±0.03)×10⁴/mL,(0.05±0.02)×10⁴/mL,(0.32±0.01)×10⁴/mL respectively, the differences of results were statistically significant(P<0.05).Under the effect of chemotactic agent,the directional migration capability of neutrophils in control group 1, 0.3 mg/kg MK-801 treatment group 1 and 0.6 mg/kg MK-801 treatment group 1 were(0.85±0.11) radian,(1.00±0.11) radian,(0.96±0.10) radian respectively (P<0.05); the migration velocities of neutrophils were (0.09±0.02) μm/s,(0.12±0.01) μm/s,(0.14±0.01) μm/s respectively (P<0.05);the migration distances of neutrophils were (94.26±0.02) μm,(134.61±0.01) μm,(156.19±0.01) μm respectively(P<0.05).

CONCLUSION

Compared with neutrophils in peritoneal cavity of control group, the neutrophils in peritoneal cavity of schizophrenic rats have stronger chemotactic movement ability.

A MoS2-based coplanar neuron transistor for logic applications

The human brain is an extremely complex system of 10¹⁰-10¹¹ neurons. To construct brain-like neuromorphic hardware, the neuron unit should be implemented effectively. Here, we report a neuron transistor based on a MoS₂ flake, which has summation and threshold functions similar to biological neurons and may act as a basic neuron unit in neuromorphic hardware. The neuron transistor is composed of a floating gate and two control gates. A heavily doped silicon substrate serves as the floating gate, while the two control gates are capacitively coupled with the floating gate. The neuron transistor can be well controlled by the two control gates individually or simultaneously. The drain current can be modulated by the input voltages at the control gates. While the current response of the neuron transistor has a large dependence on the magnitude of the input signal, it shows little dependence on the frequency of the input signal. To demonstrate the potential neuromorphic application of the neuron transistor, functions including abacus-like function, AND logic and OR logic are realized in the neuron transistor.

Highly spectrum-selective ultraviolet photodetector based on p-NiO/n-IGZO thin film heterojunction structure

Ultraviolet photodetector with p-n heterojunction is fabricated by magnetron sputtering deposition of n-type indium gallium zinc oxide (n-IGZO) and p-type nickel oxide (p-NiO) thin films on ITO glass. The performance of the photodetector is largely affected by the conductivity of the p-NiO thin film, which can be controlled by varying the oxygen partial pressure during the deposition of the p-NiO thin film. A highly spectrum-selective ultraviolet photodetector has been achieved with the p-NiO layer with a high conductivity. The results can be explained in terms of the "optically-filtering" function of the NiO layer.

Safety, cost-effectiveness and feasibility of daycase paracentesis in the management of malignant ascites with a focus on ovarian cancer

BACKGROUND

Paracentesis for malignant ascites is usually performed as an in-patient procedure, with a median length of stay (LoS) of 3-5 days, with intermittent clamping of the drain due to a perceived risk of hypotension. In this study, we assessed the safety of free drainage and the feasibility and cost-effectiveness of daycase paracentesis.

METHOD

Ovarian cancer admissions at Hammersmith Hospital between July and October 2009 were audited (Stage 1). A total of 21 patients (Stage 2) subsequently underwent paracentesis with free drainage of ascites without intermittent clamping (October 2010-January 2011). Finally, 13 patients (19 paracenteses, Stage 3), were drained as a daycase (May-December 2011).

RESULTS

Of 67 patients (Stage 1), 22% of admissions and 18% of bed-days were for paracentesis, with a median LoS of 4 days. In all, 81% of patients (Stage 2) drained completely without hypotension. Of four patients with hypotension, none was tachycardic or symptomatic. Daycase paracentesis achieved complete ascites drainage without complications, or the need for in-patient admission in 94.7% of cases (Stage 3), and cost £954 compared with £1473 for in-patient drainage.

CONCLUSIONS

Free drainage of malignant ascites is safe. Daycase paracentesis is feasible, cost-effective and reduces hospital admissions, and potentially represents the standard of care for patients with malignant ascites.

Factors influencing hospital readmission rates after acute medical treatment

It is a concern that increasing pressure to diagnose, treat and discharge patients rapidly is leading to unacceptably high readmission rates. Readmissions were studied over a two-month period. Patients were identified through the hospital coding system, and electronic discharge summaries provided details of each admission. In total, 69 readmissions were identified, representing 4.34% of medical admissions. Readmitted patients were older than those with single admissions (median age 75 and 71 years, respectively; p < 0.05). Initial length of stay was greater in those patients who would go on to be readmitted (median six days; single admission, two days; p < 0.0001). Seventy-one per cent of readmissions were deemed avoidable, with discharge before conclusive therapy being the leading factor implicated (56%). Readmission is more likely in older patients with complex care needs. Rapid throughput of patients is not associated with readmission. The majority of readmissions can potentially be avoided with judicious medical care.

[Study of the charge transfer reaction between clotrimazolum and alizarin red]

The charge transfer reaction between clotrimazolum and alizarin red was studied spectrophotometrically. The reaction was achieved with good results in water-acetone solution. The apparent molar absorptivity is 8.7 x 10(3) L.mol-1.cm-1 at 525 nm. The Beer's law was obeyed in the range of 0-100 micrograms.mL-1 of clotrimazolum. The composition of the complex is 1:1. The proposed method has been applied successfully to the determination of clotrimazolum tablets.

The effect of arsenic trioxide on the expression of Hsc and HNF4 in nuclear matrix proteins in HepG2 cells

Anticancer agents interfere with the proliferation and survival of tumor cells by a variety of mechanisms. An important factor in the development of a cytotoxic effect by certain anticancer agents is the localization of drug-induced lesions within the cell nucleus. Drug-target interactions at the level of nuclear matrix (NM) may be critical events in the induction of cell death by some of these agents. Arsenic trioxide (As2O3) was identified as a very potent anti-leukemic agent by inducing apoptosis. The present study shows that As2O3 significantly inhibits the growth of hepatoblastoma cell line, HepG2, changes the composition of nuclear matrix proteins and reduces the expression of Hsc 70 and HNF4 in HepG2, which in turn initiate a cascade of events that compromise multiple nuclear functions and, ultimately, cell survival.

Alteration of nuclear matrix protein composition of neuroblastoma cells after arsenic trioxide treatment

The aims of the present study were to assess the effects of arsenic trioxide on the nuclear matrix protein profiles of mouse neuroblastoma cells. Arsenic trioxide induces apoptosis of acute promyelocytic leukemia cells. Our results demonstrated that 2 microM As2O3 could significantly inhibit the growth of Neuro-2a cells. As early as 24 hours after As2O3 treatment, we began to observe the alteration of nuclear matrix proteins and apoptosis in tumor cells by TUNEL assay but not by DNA ladder. An increase expression of Hsc in nuclear matrix proteins of 2 microM As2O3 treated cells was also noted. Our results also showed that before a mass range of apoptosis occurred, the composition of nuclear matrix proteins had altered. Hence the alteration of nuclear matrix proteins, such as increased expression of Hsc, may be a sensitive indicator for the detection of early apoptosis.

Telemedicine screening of glaucoma

OBJECTIVES

Glaucoma is a major cause of blindness. More than 80,000 Americans suffer permanent vision loss from the disease. Widespread screening is fundamental in limiting the incidence of glaucoma-associated blindness. This pilot study explored the use of stereo digital images taken at a primary care center for telemedicine review by an off-site specialist as a means of screening for glaucoma.

MATERIALS AND METHODS

Thirty-two diabetic patients were screened at a family medicine clinic. None had previously been diagnosed with glaucoma. A senior optometry student took stereoscopic digital and 35-mm optic disc photographs with a nonmydriatic retinal camera. The digital images were forwarded to a remote ophthalmologist for review. The conventional color stereo slide pairs of the same eyes were subsequently reviewed for comparison. Agreement on signs of glaucomatous disc changes between the two imaging systems was analyzed.

RESULTS

Twenty-six of 32 eyes' digital and 35-mm photographs were analyzed. Six of 32 eyes (18.8%) could not be compared due to lack of matching 35-mm slides or digital images. Out of 26 eyes, lamina cribosa visibility was undeterminable in 8 eyes' digital images and 3 other eyes' 35-mm slides. Agreement among digital images and 35-mm slides of the remaining eyes was: 100%-vertical elongation, barring of vessels, bayoneting of vessels, and drance hemorrhage; 96.2%-focus notching of rim and rim pallor; 93.3%-lamina cribosa visability; 92. 3%-overpass cupping; 88.5%-focal enlargement; 84.6%-parapapillary halo; 80%-nerve fiber visibility; 65.4%-parapapillary atrophy. Parapapillary halo (p = 0.046) and nerve fiber layer visibility (p = 0.18) were detected on some 35-mm slides but not seen on matching digital views.

CONCLUSION

Evaluations of cup-to-disc ratio (C/D) using both methods were in general agreement. However, some digital images were noted as too dark for assessing fine glaucomatous disc changes. Stereo digital images taken with a nonmydriatic camera by nonophthalmic photographers is a promising alternative for glaucoma screening in primary care settings. Telemedicine offers efficient communications with off-site glaucoma specialists. A larger study population is necessary to determine the overall effectiveness of using stereo digital imagery and teleophthalmology for glaucoma screening.

The measurement of AgNORs in human glioma cells

Sixty gliomas obtained by neurosurgical resections were examined. Paraffin blocks were retrieved from pathological files of the Second Affiliated Hospital in Guangzhou Medical College. The methods of argyrophilic technique for AgNORs staining, and Image Analysis System for measurement of AgNORs were used. Six parameters, which included hcount, count, narea, agnrea, agpern and agperc were used to correlated well with histopathological grades (compared grade 2 & 3, grade 3 & 4, and grade 2 & 4, respectively). We concluded that AgNORs is useful in evaluating proliferative activity and assessing the malignancy of human gliomas. It may also be used as a target for anti-neoplastic drugs in the treatment of gliomas.

Sub-Tenon's injection for local anesthesia in posterior segment surgery

OBJECTIVE

To determine whether the sub-Tenon's parabulbar approach for local anesthesia is a safe and effective choice for posterior segment surgery.

DESIGN

Prospective, noncomparative case series.

PARTICIPANTS

Two hundred seventy-six consecutive patients underwent posterior segment surgery at the University of Texas Medical Branch.

INTERVENTION

Two hundred patients received sub-Tenon's parabulbar anesthesia containing an 11 -ml mixture of 5-ml 2% lidocaine (Xylocaine), 5-ml 0.5% bupivacaine (Marcaine), and 1 ml of 150 hyaluronidase (Wydase) units as primary anesthesia. The method did not involve a separate transcutaneous lid nerve or subconjunctival injection.

MAIN OUTCOME MEASURES

The proportion of cases receiving supplementation (significant intravenous anesthesia, intraoperative local anesthesia, or both) was estimated. Its relationship to duration of surgery and surgical procedures deemed painful was assessed. Surgery lasting 3 hours or more was considered a long duration. Both scleral buckle and cryotherapy were considered painful procedures. The proportion of cases receiving additional local anesthesia preoperatively was also evaluated. Complications associated with sub-Tenon's parabulbar injection were monitored.

RESULTS

There were 101 instances of patients receiving additional anesthesia. Nineteen received additional preoperative sub-Tenon's anesthesia, 12 received intraoperative local anesthesia supplementation, and 70 received intravenous medication. Of these 70, 19 required what the authors defined as a significant amount of intravenous medication, three of whom also received intraoperative local anesthesia supplementation. Consequently, 28 of 200 patients (14%; 95% confidence interval: 9.5, 19.6) received supplementation (significant intravenous anesthesia, intraoperative local anesthesia, or both). The proportion of cases receiving supplementation was directly related to duration of surgery. Patients involved in longer cases (51.7% vs. 7.6%; P < 0.001) and those involved in more painful procedures (48.2% vs. 8.7%; P < 0.001) were more likely to receive supplementation. Adjusting for surgery duration, a greater proportion of patients undergoing painful procedures required supplementation (31.3% vs. 0.5% for surgery < 3 hours, P = 0.003; 72.7% vs. 38.9% for surgery > or = 3 hours, P = 0.13). No associated ocular or systemic complications were observed.

CONCLUSIONS

The results of this large study demonstrate that a single injection of sub-Tenon's anesthesia is relatively safe and effective for achieving local anesthesia during vitrectomies, with or without other intraocular procedures, lasting less than 3 hours. Other types of posterior segment surgery may require supplementation if they are more painful procedures, such as scleral buckle or cryotherapy, or last longer than 3 hours.

Telemedicine and ophthalmology

Technology to create and move multimedia medical information is creating alternatives to physically transporting patients and health care professionals. Teletechnology is a physician extender, both supplementing and reinventing traditional health care delivery systems. The potential of comprehensive teleophthalmology is compelling. This article provides a historical perspective of telemedicine, describes various teleophthalmology systems, and surveys teleophthalmology in clinical consultation, research, and education programs around the world. It also discusses basic issues in applying teleophthalmology to public health.

Telemedicine enters eye care: practical experience

1. A combination of store-and-forward technology and videoconferencing technology can be used in eye care and other medical specialties. 2. Bandwidth is a rate-limiting factor for obtaining a high-resolution, real-time image. 3. Protocols, clinical and technical, must be used to implement telemedicine in an efficient and high-quality manner.

Transscleral ciliary sulcus fixation of a posterior chamber lens in an eye with congenital aniridia

A 30-year-old man with bilateral congenital aniridia presented with a subluxated cataract in the right eye. He wore a soft contact lens for aphakic correction in the fellow eye after lensectomy for a subluxated cataract. We performed pars plana lensectomy and vitrectomy with implantation of a transscleral ciliary sulcus fixated posterior chamber intraocular lens in the right eye. Good postoperative visual acuity was obtained.

Reversal of visual loss with hyperbaric oxygen treatment in a patient with Susac syndrome

PURPOSE

The purpose of the study is to report on a 34-year-old woman with Susac syndrome who presented on two separate occasions with visual acuity loss from a recurrent branch retinal artery occlusion and underwent hyperbaric oxygen treatment with favorable outcome.

METHODS

Visual acuity was 20/400 in the left eye and count fingers in the right eye after separate occlusive events. The patient underwent hyperbaric oxygen treatment on each occasion of visual acuity loss. The patient subsequently was diagnosed with Susac syndrome (microangiopathy of the retina, brain, and middle ear). The authors present visual fields, photographs, angiograms, and ancillary tests documenting diagnosis and course of treatment.

RESULTS

On each occasion, visual acuity improved to 20/25 during and was maintained after hyperbaric oxygen treatment. Visual fields showed improvement immediately after treatment.

CONCLUSION

This is the first report of hyperbaric oxygen treatment for Susac syndrome. Dramatic post-treatment visual field and acuity changes suggest benefit of treatment. Hyperbaric oxygen treatment can be considered a treatment option for visual complications of this syndrome. Susac syndrome should be included in the differential diagnosis of recurrent branch retinal artery occlusion.

Congenital cystic eye

We present a rare case of congenital cystic eye associated with holoprosencephaly and tetralogy of Fallot. The orbital cyst was diagnosed preoperatively by computed tomography (CT) scan, and we present the first magnetic resonance imaging (MRI) finding in such a disorder. The orbital cyst expanded over 7 months of follow-up. The cyst was excised in toto and studied by immunohistochemistry, and its content was analyzed biochemically. The patient achieved an acceptable cosmetic result.

Cytomegalovirus optic neuritis: characteristics, therapy and survival

Little is known about the natural history of cytomegalovirus (CMV) optic neuritis in the acquired immunodeficiency syndrome. We analyzed the clinical course of CMV optic neuritis in 30 consecutive subjects (35 eyes), and compared the survival of patients with CMV optic neuritis to that of a group having CMV retinitis alone, with both groups matched for ganciclovir therapy. Four untreated eyes had a median final visual acuity of no light perception. The median final visual acuity was 20/100 in treated subjects with a mean follow-up of 6.6 months. Following ganciclovir treatment, 2 eyes showed visual improvement, 17 eyes had unchanged visual acuity, and 12 eyes had marked drop in acuity. Relapse occurred in 4 subjects maintained on single-dose ganciclovir, and was controlled on double-dose ganciclovir. Survival was similar in the group of CMV retinitis alone versus the group of CMV optic neuritis with retinitis. Early recognition and therapy of CMV optic neuritis protects against irreversible visual loss. CMV optic neuritis does not carry a worse prognosis for survival than CMV retinitis alone.

Frosted retinal periphlebitis in the acquired immunodeficiency syndrome

Six patients with the acquired immunodeficiency syndrome had frosted periphlebitis associated with large areas of cytomegalovirus retinitis. Following the administration of ganciclovir, periphlebitis resolved within 2-6 weeks concomitant with quieting of cytomegalovirus retinitis. Frosted retinal periphlebitis in the acquired immunodeficiency syndrome is associated with cytomegalovirus retinitis in North America. Medical treatment of cytomegalovirus retinitis leads to resolution of the periphlebitis without the need for systemic corticosteroids.

[Changes in the relaxation and compliance of the left ventricle in cardiomyopathy]

In order to study the left ventricular diastolic events in cardiomyopathy, carotid pulse tracing, electrocardiogram, phonocardiogram and apexcardiogram with its first derivatives (dA/dt) were simultaneously recorded in 240 normal subjects, 30 patients with dilated cardiomyopathy (DCM) and 44 patients with hypertrophic cardiomyopathy (HCM). Total relaxation time (TRT), total relaxation time index (TRTI), the ratio of A wave to total diastolic amplitude in apexcardiogram (A/D), diastolic amplitude time index (DATI), the ratio of RF wave in apexcardiogram to the total amplitude of apex tracing (F/H) and the variables reflecting the diastolic properties were measured to evaluate the left ventricular relaxation and compliance. Meanwhile, two variables reflecting the contractile ability of the left ventricle were measured in order to compare with the diastolic events. The results demonstrated that in normal subjects relaxation and compliance of the left ventricle showed a tendency of natural "decay" with aging and in patients with DCM and HCM these were significantly decreased, especially in patients with HCM. A/D, which reflects the left ventricular compliance, was increased in patients with HCM as compared with normal subjects (P less than 0.01) and also with patients with DCM. It means that a greater A/D is in favor of the diagnosis of HCM rather than DCM. In addition to abnormal diastolic events, systolic dysfunction, as evidenced by remarkable abnormalities of the contractile variables (PEP/LVET and R-dA/dt.I), was found as well in patients with DCM.