Near-infrared dye IRDye800CW-NHS coupled to Trastuzumab for near-infrared II fluorescence imaging in tumor xenograft models of HER-2-positive breast cancer.

Near-infrared II fluorescent probes targeting tumors for diagnostic purposes have received much attention in recent years. In this study, a fluorescent probe for the NIR-II was constructed by using IRDye800CW-NHS fluorescent dye with Trastuzumab, which was investigated for its ability to target HER-2-positive breast cancer in xenograft mice models. This probe was compared with Trastuzumab-ICG which was synthesized using a similar structure, ICG-NHS. The results demonstrated that the IRDye800CW-NHS had significantly stronger fluorescence in the NIR-I and NIR-II than ICG-NHS in the aqueous phase. And the different metabolic modes of IRDye800CW-NHS and ICG-NHS were revealed in bioimaging experiments. IRDye800CW-NHS was mainly metabolised by the kidneys, while ICG-NHS was mainly metabolised by the liver. After coupling with Trastuzumab, Trastuzumab-800CW (TMR = 5.35 ± 0.39) not only had a stronger tumor targeting ability than Trastuzumab-ICG (TMR = 4.42 ± 0.10) based on the calculated maximum tumor muscle ratio (TMR), but also had a comparatively lower hepatic uptake and faster metabolism. Histopathology analysis proved that both fluorescent probes were non-toxic to various organ tissues. These results reveal the excellent optical properties of IRDye800CW-NHS, and the great potential of coupling with antibodies to develop fluorescent probes that will hopefully be applied to intraoperative breast cancer navigation in humans.

Use of High-Resolution Ultrasonography in Anterior Subcutaneous Transposition of the Ulnar Nerve for Cubital Tunnel Syndrome.

OBJECTIVES: Cubital tunnel syndrome (CTS) is the most common form of ulnar nerve entrapment. In this study, ultrasonography (US) was used not only for diagnosis but also for operation. US findings could be used to establish the diagnosis of CTS and could demonstrate the pathological anatomy in the cubital tunnel region to guide anterior subcutaneous transposition of the ulnar nerve. METHODS: Sixty-two patients with clinical and electrophysiological evidence of ulnar nerve entrapment were included. All patients received ultrasonographic examination and anterior subcutaneous transposition of the ulnar nerve. The maximal diameter of the ulnar nerve (MDU) was measured in longitudinal views and the range of the hypoechoic area around the nerve was observed. The cross-sectional area (CSA) was also measured on transverse scans. The actual MDU was measured during operation. RESULTS: The actual MDU was 6.4 ± 0.4 mm, measured during operation. The preoperative MDU was 3.1 ± 0.2 mm. The MDU values recorded in CTS patients were greater than those in normal subjects. The range of the hypoechoic area observed on longitudinal US scans was 2.9-5.6 mm (mean, 4.1 ± 0.4 mm). CONCLUSIONS: High-resolution US can be used not only in the diagnosis of CTS, also for providing effective preoperative evaluation for the anterior subcutaneous transposition of the ulnar nerve in CTS.

Surgical decompression of painful diabetic peripheral neuropathy: the role of pain distribution.

OBJECTIVE: To investigate the effect of surgical decompression on painful diabetic peripheral neuropathy (DPN) patients and discuss the role which pain distribution and characterization play in the management of painful DPN as well as the underlying mechanism involved. METHODS: A total of 306 patients with painful diabetic lower-extremity neuropathy were treated with Dellon surgical nerve decompression in our department. Clinical evaluation including Visual analogue scale (VAS), Brief Pain Inventory Short Form for diabetic peripheral neuropathy (BPI-DPN) questionnaire, two-point discrimination (2-PD), nerve conduction velocity (NCV) and high-resolution ultrasonography (cross-sectional area, CSA) were performed in all cases preoperatively, and at 6 month intervals for 2 years post-decompression. The patients who underwent surgery were retrospectively assigned into two subgroups (focal and diffuse pain) according to the distribution of the diabetic neuropathic pain. The control group included 92 painful DPN patients without surgery. RESULTS: The levels of VAS, scores in BPI-DPN, 2-PD, NCV results and CSA were all improved in surgical group when compared to the control group (P<0.05). More improvement of VAS, scores in BPI-DPN and CSA was observed in focal pain group than that in diffuse group (P<0.05). CONCLUSIONS: Efficacy of decompression of multiple lower-extremity peripheral nerves in patients with painful diabetic neuropathy was confirmed in this study. While both focal and diffuse group could benefit from surgical decompression, pain relief and morphological restoration could be better achieved in focal group.

Analysis of therapeutic effect of microvascular decompression surgery on idiopathic hemifacial spasm.

OBJECTIVE: The objective of this paper is to study the therapeutic effect of microvascular decompression surgery on idiopathic hemifacial spasm with compression on different zones of facial nerve. METHODS: The clinical data of 348 patients with idiopathic hemifacial spasm treated by microvascular decompression surgery were retrospectively analyzed. Patients were divided into 5 groups according to compression on different zones of facial nerve by offending vessels. Root exit point was compressed in 18 patients (group A), transitional zone of brainstem was compressed in 42 patients (group B), attached segment of brainstem was compressed in 35 patients (group C), distal cisternal portion was compressed in 21 patients (group D), and 2 or more zones were compressed in 232 patients (group E). The therapeutic effect was observed, and outcome of excellent and partial good were regarded as effective. RESULTS: Patients were followed up for 0.5 to 2 years. The effective rates were 94.4%, 95.2%, 97.1%, 95.2%, and 93.9% in group A, group B, group C, group D, and group E, respectively.No death occurred during operation,and there were no severe complications such as complete facial paralysis, intracranial hematoma, and hearing loss after operation. CONCLUSION: Microvascular decompression surgery is the first choice for treatment hemifacial spasm. Proper detection of offending vessels and complete decompression may be the key factors to increase the cure rate.

Surgical skills of adhesions and transposition of trigeminal nerve for primary trigeminal neuralgia.

OBJECTIVE: The aims of this study were to investigate disposal of adhesions and transposition of the trigeminal nerve during microvascular decompression and evaluate its surgical effect. METHODS: By collecting the clinical data of typical trigeminal neuralgia patients we treated from January 2013 to May 2013, we chose 120 patients with adhesions and transposition of trigeminal nerve, analyzed their preoperative imaging features and surgical procedures, and evaluated postoperative effect after 3-month follow-up. RESULTS: Among these 120 patients, 113 cases showed positive effect in magnetic resonance imaging (three-dimensional time-of-flight); the positive rate was 94.2%. During the operation, firstly we proceed to separate the nerve and artery, secondly we released the vascular compression, finally we removed the superior cerebellar artery to the nerve's head end. Postoperative effect evaluation stated that 101 patients showed immediate remission and 13 patients showed delayed remission (3 min after operation) and the surgery was ineffective for 6 patients; the remission rate was 95%. There were no severe complications. CONCLUSIONS: Magnetic resonance imaging (three-dimensional time-of-flight) before operation could clearly display the neurovascular relationship of trigeminal neuralgia patients. It offers great help for preoperative evaluation. Separation between arachnoid, nerve, and artery; vascular decompression; and removal of the superior cerebellar artery to the head end could resolve adhesions and transposition of trigeminal nerve during microvascular decompression, which showed significant effects.

Impact of diabetes mellitus duration on effect of lower extremity nerve decompression in 1,526 diabetic peripheral neuropathy patients.

BACKGROUND: Diabetic peripheral neuropathy (DPN) is one of the most common complications of diabetes mellitus (DM). The aim of this study was to analyze DM duration in the prognosis of diabetic peripheral neuropathy of the lower extremity. METHODS: A total of 1,526 DPN patients who were treated with DELLON surgical nerve decompression were divided into a short DM duration group and long DM duration group using a length of 5 years as the standard duration. Before and 1.5 years after surgery, high-resolution ultrasound, quantitative sensory testing (QST), and nerve conduction velocity (NCV) were performed and compared to the normal control. RESULTS: Postoperative NCV of all the patients in either treatment group significantly increased (p < 0.05) and postoperative CSA significantly decreased (p < 0.05) compared with that before surgery. The CPT significantly increased compared with the preoperative value (p < 0.05). The postoperative WPT was significantly lower than the preoperative value (p < 0.01), and the postoperative VPT was significantly lower than the preoperative value (p < 0.05). Overall, the postoperative NCV, CSA, CPT, WPT, and VPT values from the short DM duration group were significantly different from that of the long DM duration group (p < 0.05). CONCLUSIONS: The duration of DM is critical to the prognosis of DPN of the lower extremity, and the data from this study suggest that an early diagnosis and subsequent surgery for DPN have important clinical value.

Clinical characteristics and surgical techniques of trigeminal neuralgia caused simply by venous compression.

OBJECTIVE: The objective of this study was to introduce the operation essentials for treatment of patients with vein compression so as to obtain a satisfactory decompression without sacrificing veins. METHODS: We chose 15 patients with trigeminal neuralgia caused by venous from June 15, 2010, through June 15, 2011, and performed microvascular decompression for each patient. By collecting clinical data, such as preoperative magnetic resonance imaging scans, key operative procedures, surgical outcomes, and complications, we explored the operation techniques for these patients and finally summarized our experiences and ideas. RESULTS: For all the 15 patients, 9 cases had excellent remission, 3 cases had delayed excellent remission, 1 case had good remission, and 2 cases had failed result; the total remission rate was 86.7%; 3 cases had facial numbness. CONCLUSIONS: For patients with vein compression, we combine the following 4 procedures together: (1) fully releasing the arachnoid around trigeminal nerve, (2) exploration and decompression of the whole trigeminal root from Meckel cave to pons, (3) cauterization of companioned petrosal vein tributaries by bipolar coagulation, and (4) placing Teflon between trigeminal nerve and offending petrosal vein, thus could acquire a satisfactory effect (remission rate, 86.7%).

Evaluation of the clinical efficacy of multiple lower-extremity nerve decompression in diabetic peripheral neuropathy.

OBJECTIVE: To evaluate the value of high-resolution ultrasonography and neural electrophysiology in early diagnosis, operative opportunity selection, and clinical effect assessment of DPN. METHODS: Five hundred and sixty patients with diabetic peripheral neuropathy (DPN) were treated with DELLON surgical nerve decompression in our hospital in the past 5 years. Before and after 18 months surgery, the tests of the Toronto clinical scoring system, high-resolution ultrasonography, QST, and Nerve Conduction Velocity (NCV) were evaluated in all cases. The control group included 40 diabetic patients in the same age range but without DPN. RESULTS: Ultrasonographic images revealed an apparently normal proximal common peroneal nerve, tibial nerve marked swelling, enlarged, and hypoechogeneity with loss fascicular pattern. The cross-sectional-area, anteroposterior and transverse diameter were measured preoperative and prooperative, and the differences had statistical significance (P < 0.01). NCV-positive cases amount to 74.9% DPN patients in this study and QST-positive cases amount to 90.9% and had significant differences between them (P < 0.05). Postoperative NCV and cold perception threshold significantly increased (P < 0.05) compared with that of the before surgery. Postoperative warm perception threshold (P < 0.01) and vibration perception threshold (P < 0.05) were significantly lower than the preoperative value. NCV was positively correlated with cold perception threshold (r = 0.395, P < 0.01), and negatively correlated with warm perception threshold (r = - 0.387, P < 0.01) and vibratory perception threshold (r = - 0.367, P < 0.01). The preoperative TCSS score was 19 points for all the cases, and 420 cases (75%) improved to 10-13 points (P < 0.01). CONCLUSION: Ultrasonography is capable of depicting these nerves morphological information, with respect to exact location, course, and extent. QST is suitable for early diagnosis of DPN, and abnormal QST is an indication of lower extremity nerve decompression for DPN. The joint use of QST and NCV testing helps surgeons to grasp the timing of surgery. High-resolution ultrasound, QST and NCV testing can also be used as an outcome index for surgical treatment.

Construction and operation of a microrobot based on magnetotactic bacteria in a microfluidic chip.

Magnetotactic bacteria (MTB) are capable of swimming along magnetic field lines. This unique feature renders them suitable in the development of magnetic-guided, auto-propelled microrobots to serve in target molecule separation and detection, drug delivery, or target cell screening in a microfluidic chip. The biotechnology to couple these bacteria with functional loads to form microrobots is the critical point in its application. Although an immunoreaction approach to attach functional loads to intact MTB was suggested, details on its realization were hardly mentioned. In the current paper, MTB-microrobots were constructed by attaching 2 µm diameter microbeads to marine magnetotactic ovoid MO-1 cells through immunoreactions. These microrobots were controlled using a special control and tracking system. Experimental results prove that the attachment efficiency can be improved to ∼30% via an immunoreaction. The motility of the bacteria attached with different number of loads was also assessed. The results show that MTB can transport one load at a velocity of ∼21 µm/s and still move and survive for over 30 min. The control and tracking system is fully capable of directing and monitoring the movement of the MTB-microrobots. The rotating magnetic fields can stop the microrobots by trapping them as they swim within a circular field with a controllable size. The system has potential use in chemical analyses and medical diagnoses using biochips as well as in nano/microscale transport.

Phototaxis in the magnetotactic bacterium Magnetospirillum magneticum strain AMB-1 is independent of magnetic fields.

Magnetotactic bacteria (MTB) can rapidly relocate to optimal habitats by magneto-aerotaxis. Little is known about MTB phototaxis, a response that might also aid navigation. In this study, we analyzed the relationship between phototaxis and magnetotaxis in Magnetospirillum magneticum strain AMB-1. Magnotactic AMB-1 cells migrated toward light, and migration increased with higher light intensity. This response was independent of wavelength, as AMB-1 cells migrated equally toward light from 400 to 750 nm. When AMB-1 cells were exposed to zero magnetic fields or to 0.2 mT magnetic fields that were opposite or orthogonal to the light beam, cells still migrated toward the light, indicating that phototaxis was independent of magnetotaxis. The R(mag) value and coercive force (H(c)) of AMB-1 increased when the bacteria were illuminated for 20 h, consistent with an increase in magnetosome synthesis or in magnetosome-containing cells. These results demonstrated that the M. magneticum AMB-1 responded to light as well as other environmental factors. To our knowledge, this is the first report of phototactic behavior in the bacteria of Magnetospirillum.

Effects of pulsed magnetic field on the formation of magnetosomes in the Magnetospirillum sp. strain AMB-1.

Magnetotactic bacteria are a diverse group of microorganisms which possess one or more chains of magnetosomes and are endowed with the ability to use geomagnetic fields for direction sensing, thus providing a simple and excellent model for the study of magnetite-based magnetoreception. In this study, a 50 Hz, 2 mT pulsed magnetic field (PMF) was applied to study the effects on the formation of magnetosomes in Magnetospirillum sp. strain AMB-1. The results showed that the cellular magnetism (R(mag)) of AMB-1 culture significantly increased while the growth of cells remained unaffected after exposure. The number of magnetic particles per cell was enhanced by about 15% and slightly increased ratios of magnetic particles of superparamagnetic property (size <20 nm) and mature magnetosomes (size >50 nm) were observed after exposure to PMF. In addition, the intracellular iron accumulation slightly increased after PMF exposure. Therefore, it was concluded that 50 Hz, 2 mT PMF enhances the formation of magnetosomes in Magnetospirillum sp. strain AMB-1. Our results suggested that lower strength of PMF has no significant effects on the bacterial cell morphologies but could affect crystallization process of magnetosomes to some extent.