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1.
Anal Chem ; 90(8): 5122-5129, 2018 04 17.
Article in English | MEDLINE | ID: mdl-29557164

ABSTRACT

This study reports on a hand-held volatilome analyzer for selective determination of clinically relevant biomarkers in exhaled breath. The sensing platform is based on electrospun polymer nanofiber-multiwalled carbon nanotube (MWCNT) sensing microchannels. Polymer nanofibers of poly(vinylidene fluoride) (PVDF), polystyrene (PS), and poly(methyl methacrylate) (PMMA) incorporated with MWCNT exhibits a stable response to interferences of humidity and CO2 and provides selective deformations upon exposure of exhaled breath target volatilomes acetone and toluene, exhibiting correlation to diabetes and lung cancer, respectively. The sensing microchannels "P1" (PVDF-MWCNT), "P2" (PS-MWCNT), and "P3" (PMMA-MWCNT) are integrated with a microfluidic cartridge (µ-card) that facilitates collection and concentration of exhaled breath. The volatilome analyzer consists of a conductivity monitoring unit, signal conditioning circuitries and a low energy display module. A combinatorial operation algorithm was developed for analyzing normalized resistivity changes of the sensing microchannels upon exposure to breath in the concentration ranges between 35 ppb and 3.0 ppm for acetone and 1 ppb and 10 ppm for toluene. Subsequently, responses of volatilomes from individuals in the different risk groups of diabetes were evaluated for validation of the proposed methodology. We foresee that proposed methodology provides an avenue for rapid detection of volatilomes thereby enabling point of care diagnosis in high-risk group individuals.


Subject(s)
Breath Tests/methods , Nanofibers/analysis , Volatile Organic Compounds/analysis , Acetone/analysis , Breath Tests/instrumentation , Diabetes Mellitus/diagnosis , Diabetes Mellitus/metabolism , Humans , Lung Diseases/diagnosis , Lung Diseases/metabolism , Microfluidic Analytical Techniques , Nanotubes, Carbon/chemistry , Point-of-Care Systems , Polymethyl Methacrylate/chemistry , Polystyrenes/chemistry , Toluene/analysis , Volatile Organic Compounds/metabolism
2.
Opt Lett ; 39(6): 1469-72, 2014 Mar 15.
Article in English | MEDLINE | ID: mdl-24690815

ABSTRACT

An all-optical pulse controlled switch/modulator based on evanescent coupling between a polymer slab waveguide and a single mode fiber is demonstrated. Very fast all-optical modulation/switching is achieved via Kerr effect of the nonlinear polymer placed in the evanescent region of the optical fiber. Local refractive index perturbation (Δn=-1.45612×10(-5)) on the thin film leads to 0.374 nW power modulation at the fiber output, which results in a switching efficiency of ≈1.5%.

3.
Neurosurgery ; 62 Suppl 2: 540-6, 2008 Feb.
Article in English | MEDLINE | ID: mdl-18596450

ABSTRACT

OBJECTIVE: Despite advances in surgical techniques in the management of the brain abscess, long-term antibiotics are as crucial to cure as the initial surgical procedure itself. This study was designed to evaluate the effect of adjuvant hyperbaric oxygen (HBO) therapy on the duration of antibiotic treatment. METHODS: Between 1999 and 2004, 13 patients with bacterial brain abscesses treated with stereotactic aspiration combined with HBO and systemic antibiotic therapy. Patients younger than 18 years of age were excluded from this study. Postoperatively, all patients were given a 4-week course of intravenous antibiotics. Additionally, patients received hyperbaric oxygen (HBO, 100% O2 at 2.5 ATA for 60 min) twice daily for five consecutive days, and an additional treatment (100% O2 at 2.5 ATA for 60 min daily) was given for 25 days. RESULTS: There were eight male and five female patients. Their ages ranged between 18 and 71 years, with a mean of 43.9 years. The average duration of follow-up was 9.5 months (range, 8-13 mo). This treatment modality allowed infection control and healing for all 13 patients with 0% recurrence rate. HBO treatment was tolerated well, and there were no adverse effects of pressurization. At the end of the follow-up period, 12 patients had a good outcome: nine are without sequelae, and three have a mild hemiparesis but are capable of self-care. One patient has a moderate hemiparesis. CONCLUSION: Although the number of patients is small, this series represents the largest reported group of brain abscess patients treated with stereotactic aspiration combined with antibiotic and HBO therapy. Our preliminary results indicate that the length of time on antibiotics can be shortened with the use of HBO as an adjunctive treatment.

4.
Mil Med ; 172(6): 669-72, 2007 Jun.
Article in English | MEDLINE | ID: mdl-17615856

ABSTRACT

OBJECTIVE: Arachnoid cysts (ACs) of the craniocervical junction are extremely rare entities. This report describes a craniocervical junction AC with unusual clinical course at an unusual anatomical location. METHODS: A 21-year-old man was admitted to our clinic after a craniospinal trauma. Examination was unremarkable. Computed tomography scans demonstrated mild to moderately enlarged third and the lateral ventricles, but the fourth ventricle was typically normal. Neuroimaging studies obtained after the onset of clinical symptoms revealed marked enlargement of the ventricular system and a new cyst formation at the C1-2 level which was absent before. He underwent suboccipital craniectomy and C1-2 laminectomies. The cyst was fenestrated into subarachnoid space. RESULTS: He made a good recovery. The histopathological diagnosis was confirmed as AC. CONCLUSION: Due to rarity of this clinical entity, we urge readers to keep in mind the possibility of the development of this kind of AC with unusual clinical course.


Subject(s)
Arachnoid Cysts/complications , Atlanto-Axial Joint/pathology , Atlanto-Occipital Joint/pathology , Cervical Vertebrae/pathology , Hydrocephalus/etiology , Adult , Atlanto-Axial Joint/diagnostic imaging , Atlanto-Occipital Joint/diagnostic imaging , Cervical Vertebrae/diagnostic imaging , Craniocerebral Trauma/diagnostic imaging , Humans , Hydrocephalus/surgery , Laminectomy , Magnetic Resonance Imaging , Male , Risk Factors , Spinal Injuries/diagnostic imaging , Tomography, X-Ray Computed
5.
Neurol Med Chir (Tokyo) ; 47(3): 109-15; discussion 115, 2007 Mar.
Article in English | MEDLINE | ID: mdl-17384492

ABSTRACT

The diagnosis of carpal tunnel syndrome (CTS) is mainly based on the characteristic symptoms and confirmed with nerve conduction studies. Sonography can provide measurements of the increased cross-sectional area of median nerve. The use of sonography was evaluated for the diagnosis and postoperative follow up of 48 wrists in 26 consecutive patients with CTS. Clinical evaluation and sonography were effective for the diagnosis in 40 wrists. Nerve conduction studies were needed in eight wrists, because of the decrease in cross-sectional area of the nerve as a result of degenerative changes. After 3 months, sonography detected statistically significant decreases in the cross-sectional areas of the median nerves. The sonographic studies were well tolerated by all patients. Sonography was both time-saving and cost-effective.


Subject(s)
Carpal Tunnel Syndrome/diagnostic imaging , Carpal Tunnel Syndrome/surgery , Adult , Aged , Female , Follow-Up Studies , Humans , Male , Middle Aged , Prospective Studies , Reproducibility of Results , Sensitivity and Specificity , Ultrasonography
6.
Mil Med ; 171(2): 103-6, 2006 Feb.
Article in English | MEDLINE | ID: mdl-16578976

ABSTRACT

OBJECTIVE: We present a unique case of a saccular aneurysm originating from the distal end of the right frontopolar artery (FPA). METHODS: This previously healthy, 54-year-old man had sustained a mild head trauma. On admission, he was lethargic, but his neurological examination results were otherwise normal. Neuroradiological studies (including brain computed tomography, magnetic resonance imaging, and cerebral angiography) demonstrated a distal-end aneurysm of the right FPA. The aneurysm was clipped and resected via a right frontal craniotomy. RESULTS: The postoperative course was uneventful. Pathological examination of the resected specimen confirmed rupture of the wall of a true aneurysm. The patient's medical history was also negative for trauma in the past, previous neurological disease, and vascular collagen disorders. Routine angiography performed 30 days postoperatively demonstrated complete occlusion of the right FPA. The patient was free of focal neurological deficits. CONCLUSION: This case demonstrates that not all distally located aneurysms are necessarily mycotic or traumatic.


Subject(s)
Aneurysm, Ruptured/surgery , Craniocerebral Trauma/complications , Intracranial Aneurysm/surgery , Aneurysm, Ruptured/diagnosis , Aneurysm, Ruptured/etiology , Cerebral Angiography , Diagnosis, Differential , Humans , Intracranial Aneurysm/diagnosis , Intracranial Aneurysm/etiology , Magnetic Resonance Imaging , Male , Middle Aged , Tomography, X-Ray Computed
7.
Neurosurgery ; 57(6): 1140-6; discussion 1140-6, 2005 Dec.
Article in English | MEDLINE | ID: mdl-16331162

ABSTRACT

OBJECTIVE: Despite advances in surgical techniques in the management of the brain abscess, long-term antibiotics are as crucial to cure as the initial surgical procedure itself. This study was designed to evaluate the effect of adjuvant hyperbaric oxygen (HBO) therapy on the duration of antibiotic treatment. METHODS: Between 1999 and 2004, 13 patients with bacterial brain abscesses treated with stereotactic aspiration combined with HBO and systemic antibiotic therapy. Patients younger than 18 years of age were excluded from this study. Postoperatively, all patients were given a 4-week course of intravenous antibiotics. Additionally, patients received hyperbaric oxygen (HBO, 100% O2 at 2.5 ATA for 60 min) twice daily for five consecutive days, and an additional treatment (100% O2 at 2.5 ATA for 60 min daily) was given for 25 days. RESULTS: There were eight male and five female patients. Their ages ranged between 18 and 71 years, with a mean of 43.9 years. The average duration of follow-up was 9.5 months (range, 8-13 mo). This treatment modality allowed infection control and healing for all 13 patients with 0% recurrence rate. HBO treatment was tolerated well, and there were no adverse effects of pressurization. At the end of the follow-up period, 12 patients had a good outcome: nine are without sequelae, and three have a mild hemiparesis but are capable of self-care. One patient has a moderate hemiparesis. CONCLUSION: Although the number of patients is small, this series represents the largest reported group of brain abscess patients treated with stereotactic aspiration combined with antibiotic and HBO therapy. Our preliminary results indicate that the length of time on antibiotics can be shortened with the use of HBO as an adjunctive treatment.


Subject(s)
Anti-Bacterial Agents/administration & dosage , Brain Abscess/therapy , Hyperbaric Oxygenation , Stereotaxic Techniques , Suction , Adult , Aged , Anti-Bacterial Agents/therapeutic use , Brain Abscess/diagnosis , Drug Administration Schedule , Female , Humans , Hyperbaric Oxygenation/standards , Magnetic Resonance Imaging , Male , Middle Aged , Retrospective Studies , Treatment Outcome
8.
Neurosurg Rev ; 27(3): 189-93, 2004 Jul.
Article in English | MEDLINE | ID: mdl-14704860

ABSTRACT

This retrospective study included eight consecutive cases with C2 vertebral body neoplastic lesions. The anterior retropharyngeal approach was used to remove the lesions and decompress the spinal cord. Spinal stabilization with occipitocervical plating in a second-stage operation makes the treatment more tolerable for patients. The object of this study was to determine the effectiveness of a two-stage operation strategy for these lesions. Eight patients were operated on via anterior retropharyngeal approach and then stabilized with occipitocervical plates posteriorly in a second sitting. All neck pain and all dysphagia problems resolved. Partial neurologic improvement was achieved in three out of four patients. No postoperative infection was seen. The retropharyngeal approach to the upper cervical spine and anterior foramen magnum lesions is an effective alternative to transoral surgery because of low complication rates. Neoplastic lesions in the upper cervical spine can safely and effectively be operated with this technique. The general medical status of patients with malignancies does not permit too long, time-consuming operations. Stabilization of the spine in a separate operation increases patient tolerability without any morbidity.


Subject(s)
Cervical Vertebrae/surgery , Occipital Bone/surgery , Pharynx/surgery , Plasmacytoma/surgery , Spinal Fusion , Spinal Neoplasms/surgery , Aged , Breast Neoplasms/pathology , Female , Follow-Up Studies , Humans , Lung Neoplasms/pathology , Male , Middle Aged , Plasmacytoma/diagnostic imaging , Prostatic Neoplasms/pathology , Radiography , Retrospective Studies , Spinal Neoplasms/diagnostic imaging , Spinal Neoplasms/secondary , Treatment Outcome
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