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This study aimed to evaluate surface defects of Remover rotary Nickel-Titanium (NiTi) files after single and multiple uses in conventional endodontic retreatment procedures using scanning electron microscopy (SEM). Eighty acrylic blocks, simulating root canals with a 1.5 mm internal diameter, a 5 mm radius of curvature, and a 55° curvature, were utilized. After chemomechanical preparation and obturation, 24 new Remover files (N30, 7%, L23) were randomly assigned to three groups: single use, triple use, and six uses. The files were operated at 600 rpm with a torque of 2.5 Ncm, cleaned, and sterilized after each use. SEM analysis at magnifications of 100x, 250x, and 500x revealed surface defects, including tip deformation, microcracks, fracture, unwinding, surface pitting, and blade disruption. Deformation was observed in 75% of the files after a single use and in 100% of the files after three and six uses. Microcracks were absent after single use but appeared in 25% and 87.5% of files after three and six uses, respectively, showing a statistically significant increase (p < 0.001). Surface pitting also significantly increased among groups (p = 0.004). No fractures were observed in any group. The most common defects were tip deformation (91.7%) and surface pitting (70.8%). The findings suggest that repeated use of NiTi files significantly increases surface defects, elevating the risk of fatigue fractures. Thus, the results recommend limiting the reuse of Remover files to a maximum of 3x. Further research is needed to correlate defect types with anatomical factors and to assess file effectiveness in retreatment scenarios.

Background: This study assessed the consistency and accuracy of responses provided by two artificial intelligence (AI) applications, ChatGPT and Google Bard (Gemini), to questions related to dental trauma., Materials and Methods: Based on the International Association of Dental Traumatology guidelines, 25 dichotomous (yes/no) questions were posed to ChatGPT and Google Bard over 10 days. The responses were recorded and compared with the correct answers. Statistical analyses, including Fleiss kappa, were conducted to determine the agreement and consistency of the responses., Results: Analysis of 4500 responses revealed that both applications provided correct answers to 57.5% of the questions. Google Bard demonstrated a moderate level of agreement, with varying rates of incorrect answers and referrals to physicians., Conclusions: Although ChatGPT and Google Bard are potential knowledge resources, their consistency and accuracy in responding to dental trauma queries remain limited. Further research involving specially trained AI models in endodontics is warranted to assess their suitability for clinical use., (© 2024 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Introduction: Root canal retreatment often employs organic solvents like chloroform, eucalyptol, and orange oil. However, studies comparing their effectiveness yield inconsistent results. The quantity of d-limonene, a crucial component in orange oil, varies depending on the oil production method. Cold-pressed orange oil has been observed to contain the highest d-limonene levels. This study investigates the comparative solvent effects of cold-pressed and steam-hydrodistilled orange oils on gutta-percha and GuttaFlow2, typically used components in root canal fillings., Methods: Thirty-two discs (10 mm in diameter and 2 mm in thickness) were prepared using GuttaFlow and gutta-percha cones. The samples were weighed and then randomly divided into four groups (n=8) based on the type of solvent used. Each group was immersed in its respective solvent for 10 minutes. After exposure to the solvent, the samples were reweighed to determine the amount of material removed., Results: The weight loss in the group treated with cold-pressed orange oil on gutta-percha was significantly higher than in other groups (GuttaFlow2 + cold-pressed orange oil, gutta-percha + steam hydrodistilled orange oil, GuttaFlow2 + steam hydrodistilled orange oil) (p<0.001, p<0.001, and p<0.001)., Conclusion: According to the study findings, cold-pressed orange oil demonstrated a higher solvent effect on both GuttaFlow2 and traditional gutta-percha compared to steam-hydrodistilled orange oil. This indicates the significant impact of the production method of orange oil on its efficacy as a solvent in root canal therapy retreatment., Competing Interests: Human subjects: All authors have confirmed that this study did not involve human participants or tissue. Animal subjects: All authors have confirmed that this study did not involve animal subjects or tissue. Conflicts of interest: In compliance with the ICMJE uniform disclosure form, all authors declare the following: Payment/services info: All authors have declared that no financial support was received from any organization for the submitted work. Financial relationships: All authors have declared that they have no financial relationships at present or within the previous three years with any organizations that might have an interest in the submitted work. Other relationships: All authors have declared that there are no other relationships or activities that could appear to have influenced the submitted work., (Copyright © 2024, Ozden et al.)

Realizing the full potential of stretchable bioelectronics in wearables, biomedical implants and soft robotics necessitates conductive elastic composites that are intrinsically soft, highly conductive and strain resilient. However, existing composites usually compromise electrical durability and performance due to disrupted conductive paths under strain and rely heavily on a high content of conductive filler. Here we present an in situ phase-separation method that facilitates microscale silver nanowire assembly and creates self-organized percolation networks on pore surfaces. The resultant nanocomposites are highly conductive, strain insensitive and fatigue tolerant, while minimizing filler usage. Their resilience is rooted in multiscale porous polymer matrices that dissipate stress and rigid conductive fillers adapting to strain-induced geometry changes. Notably, the presence of porous microstructures reduces the percolation threshold (V c  = 0.00062) by 48-fold and suppresses electrical degradation even under strains exceeding 600%. Theoretical calculations yield results that are quantitatively consistent with experimental findings. By pairing these nanocomposites with near-field communication technologies, we have demonstrated stretchable wireless power and data transmission solutions that are ideal for both skin-interfaced and implanted bioelectronics. The systems enable battery-free wireless powering and sensing of a range of sweat biomarkers-with less than 10% performance variation even at 50% strain. Ultimately, our strategy offers expansive material options for diverse applications., (© 2024. The Author(s), under exclusive licence to Springer Nature Limited.)

Postganglionic neurons of the autonomic nervous system lie outside of the central nervous system and innervate specific target effectors such as organs or glands. The major pelvic ganglion (MPG) is one such ganglion that plays a significant role in controlling bladder function in rodents. However, because of technical and physical constraints in recording electrophysiological signals from these neurons in vivo, the functional neural activity in MPG is mostly unknown. Transgenic animal models expressing genetically encoded calcium indicators now provide opportunities to monitor the activity of populations of neurons in vivo to overcome these challenges related to traditional electrophysiological methods. However, like many peripheral neurons, the MPG is not conducive to conventional fluorescent microscopy techniques, as it is located in the pelvic cavity, thus limiting robust optical access by benchtop microscopes. Here, we present an endoscopic approach based on a custom miniscope system (UCLA V3) that allows for effective in vivo monitoring of neural activity in the MPG for the first time. We show that our imaging approach can monitor activity of hundreds of MPG neurons simultaneously during the filling and emptying of the bladder in a urethane-anesthetized transgenic mouse line expressing GCaMP6s in cholinergic MPG neurons. By using custom analysis scripts, we isolated the activity of hundreds of individual neurons and show that populations of neurons have distinct phasic activation patterns during sequential bladder filling and voiding events. Our imaging approach can be adapted to record activity from autonomic neurons across different organs and systems in both healthy and disease models. NEW & NOTEWORTHY The functional activity and information processing within autonomic ganglia is mostly unknown because of technical and physical constraints in recording electrophysiological signals from these neurons in vivo. Here, we use a micro-endoscopic approach to measure in vivo functional activity patterns from a population of autonomic neurons controlling bladder function for the first time. This approach can be adapted to record activity from autonomic neurons across different organs and systems in both healthy and disease models.

How do humans and animals perform trial-and-error learning when the space of possibilities is infinite? In a previous study, we used an interval timing production task and discovered an updating strategy in which the agent adjusted the behavioral and neuronal noise for exploration. In the experiment, human subjects proactively generated a series of timed motor outputs. Positive or negative feedback was provided after each response based on the timing accuracy. We found that the sequential motor timing varied at two temporal scales: long-term correlation around the target interval due to memory drifts and short-term adjustments of timing variability according to feedback. We have previously described these two key features of timing variability with an augmented Gaussian process, termed reward-sensitive Gaussian process (RSGP). In a nutshell, the temporal covariance of the timing variable was updated based on the feedback history to recreate the two behavioral characteristics mentioned above. However, the RSGP was mainly descriptive and lacked a neurobiological basis of how the reward feedback can be used by a neural circuit to adjust motor variability. Here we provide a mechanistic model and simulate the process by borrowing the architecture of recurrent neural networks (RNNs). While recurrent connection provided the long-term serial correlation in motor timing, to facilitate reward-driven short-term variations, we introduced reward-dependent variability in the network connectivity, inspired by the stochastic nature of synaptic transmission in the brain. Our model was able to recursively generate an output sequence incorporating internal variability and external reinforcement in a Bayesian framework. We show that the model can generate the temporal structure of the motor variability as a basis for exploration and exploitation trade-off. Unlike other neural network models that search for unique network connectivity for the best match between the model prediction and observation, this model can estimate the uncertainty associated with each outcome and thus did a better job in teasing apart adjustable task-relevant variability from unexplained variability. The proposed artificial neural network model parallels the mechanisms of information processing in neural systems and can extend the framework of brain-inspired reinforcement learning (RL) in continuous state control., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Wang, El-Jayyousi and Ozden.)

Mitochondrial Ca 2+ plays a critical role in controlling cytosolic Ca 2+ buffering, energy metabolism, and cellular signal transduction. Overloading of mitochondrial Ca 2+ contributes to various pathological conditions, including neurodegeneration and apoptotic cell death in neurological diseases. Here we present a cell-type specific and mitochondria targeting molecular approach for mitochondrial Ca 2+ imaging in astrocytes and neurons in vitro and in vivo. We constructed DNA plasmids encoding mitochondria-targeting genetically encoded Ca 2+ indicators (GECIs) GCaMP5G or GCaMP6s (GCaMP5G/6s) with astrocyte- and neuron-specific promoters gfaABC1D and CaMKII and mitochondria-targeting sequence (mito-). For in vitro mitochondrial Ca 2+ imaging, the plasmids were transfected in cultured astrocytes and neurons to express GCaMP5G/6s. For in vivo mitochondrial Ca 2+ imaging, adeno-associated viral vectors (AAVs) were prepared and injected into the mouse brains to express GCaMP5G/6s in mitochondria in astrocytes and neurons. Our approach provides a useful means to image mitochondrial Ca 2+ dynamics in astrocytes and neurons to study the relationship between cytosolic and mitochondrial Ca 2+ signaling, as well as astrocyte-neuron interactions.

Propolis is a candidate for cancer treatment with its activity against different tumor cells and, has a wide spectrum of biological and pharmacological activities due to the diversity of its components. In this study, antitumorigenic activities of ethanol extract of propolis (EEP) and ethanol extract of propolis loaded niosome (PLN) were compared using 2D and 3D cell culture. Niosome formulations were prepared by thin film hydration technique. Cell viability of EEP and PLN was analyzed on MCF7, A549, MDA-MB-231, SK-MEL, SK-BR-3, DU145 and L-929 cell lines using MTT assay. L929, MCF7 and A549 cells were cultured using the 3D petri dish technique and their spherical forms were obtained after 142 h. After 24 h, PLN and EEP application, cell viability analysis was performed on 3D cultures with WST assay. As a result, niosome formulations containing EEP showed higher activity than ethanol extract of propolis in cancer cells. While a slow decrease was observed in cell viability in EEP treated cancer cells, it was observed that the percentage viability rates decreased in a shorter time in PLN treated cancer cells. Also, PLN can be used as an anticancer activity drug such as Doxorubicin, but this is not the case for EEP.

Background: Choledochal cysts are congenital anomalies that can occur at any level of the biliary tree. They carry long-term risk of biliary complications and cancer development. Complete excision of all involved bile ducts is recommended., Methods: Patients treated between 1995 and 2019 were reviewed retrospectively., Results: Sixty patients; 46 female and 14 male with a median age of 41 years (range 13-83) were included in the study. Mild abdominal pain was the most common presenting symptom (60%). Majority of the patients had Todani type I cysts (67%). Concomitant biliary malignancy was diagnosed in five patients (9%). Eight patients were followed-up conservatively (13%). Twenty-five patients were treated by excision of the extrahepatic bile ducts and Roux-en-Y hepaticojejunostomy, liver resection was added in seven, pancreatoduodenectomy was done in three and liver transplantation in one. There was no perioperative mortality. Postoperative complications developed in 17 patients (34%), two requiring surgical treatment. Four of the five patients with malignancies died at a median 42 months (range 6-95) following surgery. Median 62 months (range 8-280) follow-up was available in 45 surgically treated patients, 19 followed-up for more than 10 years. None of the patients developed malignancy during follow-up. Four patients (17%) were readmitted for anastomotic strictures requiring treatment., Conclusion: The majority of choledochal cysts are Todani type-I and early cyst excision is the mainstay of management, which may decrease the risk of malignant transformation., (Copyright © 2020 Royal College of Surgeons of Edinburgh (Scottish charity number SC005317) and Royal College of Surgeons in Ireland. Published by Elsevier Ltd. All rights reserved.)

Background: Iatrogenic factors persist as leading mechanisms of cholangitis at a referral center., Methods: The records of 51 patients treated for cholangitis due to incomplete or inappropriate nonoperative biliary interventions between 2005-2016 were evaluated retrospectively., Results: Twenty-nine patients were men; median (range) age was 60 (30-90). An incomplete or inappropriate ERCP and percutaneous transhepatic biliary drainage (PTBD) had been performed in 45 and 6 patients respectively. Inappropriate endoscopic stenting for hilar obstruction (perihilar cholangiocarcinoma: 22 and gallbladder carcinoma:3) was the most common scenario (n: 25, 49%). Twenty other patients had undergone an ERCP with incomplete (n: 12) or no (n:8) drainage. The errors in the PTBD group were passage of the catheter to the duodenum in patients with hilar obstruction (n: 4) and incomplete drainage in patients with perihilar cholangiocarcinoma (n: 2). Two patients (4%) died of infection. The surgery of 6 operable tumor patients was delayed for median (range) 5 (1-7) months., Conclusions: Incomplete or inappropriate nonoperative biliary interventions put patients' lives at risk and delay radical treatments.

Background: Widespread opsin expression in the cortex of rats, where transgenic models have not been established, is not practical to achieve with the traditional diffusion-based virus transduction methods (DBD)., New Method: We developed protocols for convection-enhanced delivery (CED) of virus for optogenetic transduction of the rat cortex. Targeting the motor forelimb area as an example, we performed dual-site CED (6μL of virus per site, 3mm pitch between sites) in the rat motor cortex., Results: We identified injection parameters optimized for horizontal spread of infusate in the agarose gel model and then demonstrated in vivo widespread opsin expression over the cortical area (7.4±1.0mm in the AP direction, 4.4±1.1mm in the ML direction, N=13 rats) using CED. The optogenetic transduction was also functionally robust, in which both optical modulation of neuronal activity and elicitation of overt motor responses was reliably observed., Comparison With Existing Method(s): CED led to about 24-fold increase in the volume of opsin expression, compared with the conventional DBD method. The total injection time was also reduced by at least 10 times, if similar extent of expression were to be achieved with the conventional DBD method., Conclusions: CED is a reliable and effective method of virus delivery for optogenetic transduction of planar superficial structures, such as the cortex in rats., (Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.)

Cerebellar granule cells, which constitute half the brain's neurons, supply Purkinje cells with contextual information necessary for motor learning, but how they encode this information is unknown. Here we show, using two-photon microscopy to track neural activity over multiple days of cerebellum-dependent eyeblink conditioning in mice, that granule cell populations acquire a dense representation of the anticipatory eyelid movement. Initially, granule cells responded to neutral visual and somatosensory stimuli as well as periorbital airpuffs used for training. As learning progressed, two-thirds of monitored granule cells acquired a conditional response whose timing matched or preceded the learned eyelid movements. Granule cell activity covaried trial by trial to form a redundant code. Many granule cells were also active during movements of nearby body structures. Thus, a predictive signal about the upcoming movement is widely available at the input stage of the cerebellar cortex, as required by forward models of cerebellar control.

Optogenetics, the selective excitation or inhibition of neural circuits by light, has become a transformative approach for dissecting functional brain microcircuits, particularly in in vivo rodent models, owing to the expanding libraries of opsins and promoters. Yet there is a lack of versatile devices that can deliver spatiotemporally patterned light while performing simultaneous sensing to map the dynamics of perturbed neural populations at the network level. We have created optoelectronic actuator and sensor microarrays that can be used as monolithic intracortical implants, fabricated from an optically transparent, electrically highly conducting semiconductor ZnO crystal. The devices can perform simultaneous light delivery and electrical readout in precise spatial registry across the microprobe array. We applied the device technology in transgenic mice to study light-perturbed cortical microcircuit dynamics and their effects on behavior. The functionality of this device can be further expanded to optical imaging and patterned electrical microstimulation.

Dopamine (DA) release and uptake dynamics in the nucleus accumbens (NAc) have important implications for neurological diseases and mammalian animal behaviors. We demonstrate here the use of cell-type-specific optogenetic targeting in conjunction with fast-scan cyclic voltammetry applied to brain slices prepared from specifically tailored transgenic mice, which conditionally express channelrhodopsin-2 (ChR2) through dopamine transporter (DAT)-Cre. Terminal dopaminergic dynamics and the direct manipulation of induced DA release level by controlling light intensity, pulse width, and the shape of stimulation waveforms were studied. Effective cell terminal-targeting optogenetic induction of DA release at physiological levels in NAc is demonstrated and discussed. It was found that delivering more light energy by increasing stimulation intensity and length is not the only way to control DA release; the temporal shape of the stimulus waveform at light onset is also critically related to induced DA concentrations. In addition, DA uptake dynamics as well as the recovery of the presynaptic releasable DA pool are studied and modeled. More broadly, our experimental findings provide important further evidence for effectively applying optogenetics to induce neurotransmitter release in the behaviorally relevant region of the brain in a highly cell-type selective context.

Attracted by the appealing advantages of optogenetics, many nonhuman primate labs are attempting to incorporate this technique in their experiments. Despite some reported successes by a few groups, many still find it difficult to develop a reliable way to transduce cells in the monkey brain and subsequently monitor light-induced neuronal activity. Here, we describe a methodology that we have developed and successfully deployed on a regular basis with multiple monkeys. All devices and accessories are easy to obtain and results using these have been proven to be highly replicable. We developed the "in-chair" viral injection system and used tapered and thinner fibers for optical stimulation, which significantly improved the efficacy and reduced tissue damage. With these methods, we have successfully transduced cells in multiple monkeys in both deep and shallow cortical areas. We could reliably obtain neural modulation for months after injection, and no light-induced artifacts were observed during recordings. Further experiments using these methods have shown that optogenetic stimulation can be used to bias spatial attention in a visual choice discrimination task in a way comparable to electrical microstimulation, which demonstrates the potential use of our methods in both fundamental research and clinical applications.

Transient gamma-band (40-80 Hz) spatiotemporal patterns are hypothesized to play important roles in cortical function. Here we report the direct observation of gamma oscillations as spatiotemporal waves induced by targeted optogenetic stimulation, recorded by intracortical multichannel extracellular techniques in macaque monkeys during their awake resting states. Microelectrode arrays integrating an optical fiber at their center were chronically implanted in primary motor (M1) and ventral premotor (PMv) cortices of two subjects. Targeted brain tissue was transduced with the red-shifted opsin C1V1(T/T). Constant (1-s square pulses) and ramp stimulation induced narrowband gamma oscillations during awake resting states. Recordings across 95 microelectrodes (4 × 4-mm array) enabled us to track the transient gamma spatiotemporal patterns manifested, e.g., as concentric expanding and spiral waves. Gamma oscillations were induced well beyond the light stimulation volume, via network interactions at distal electrode sites, depending on optical power. Despite stimulation-related modulation in spiking rates, neuronal spiking remained highly asynchronous during induced gamma oscillations. In one subject we examined stimulation effects during preparation and execution of a motor task and observed that movement execution largely attenuated optically induced gamma oscillations. Our findings demonstrate that, beyond previously reported induced gamma activity under periodic drive, a prolonged constant stimulus above a certain threshold may carry primate motor cortex network dynamics into gamma oscillations, likely via a Hopf bifurcation. More broadly, the experimental capability in combining microelectrode array recordings and optogenetic stimulation provides an important approach for probing spatiotemporal dynamics in primate cortical networks during various physiological and behavioral conditions.

Neuroprosthesis research aims to enable communication between the brain and external assistive devices while restoring lost functionality such as occurs from stroke, spinal cord injury or neurodegenerative diseases. In future closed-loop sensorimotor prostheses, one approach is to use neuromodulation as direct stimulus to the brain to compensate for a lost sensory function and help the brain to integrate relevant information for commanding external devices via, e.g. movement intention. Current neuromodulation techniques rely mainly of electrical stimulation. Here we focus specifically on the question of eliciting a biomimetically relevant sense of touch by direct stimulus of the somatosensory cortex by introducing optogenetic techniques as an alternative to electrical stimulation. We demonstrate that light activated opsins can be introduced to target neurons in the somatosensory cortex of non-human primates and be optically activated to create a reliably detected sensation which the animal learns to interpret as a tactile sensation localized within the hand. The accomplishment highlighted here shows how optical stimulation of a relatively small group of mostly excitatory somatosensory neurons in the nonhuman primate brain is sufficient for eliciting a useful sensation from data acquired by simultaneous electrophysiology and from behavioral metrics. In this first report to date on optically neuromodulated behavior in the somatosensory cortex of nonhuman primates we do not yet dissect the details of the sensation the animals exerience or contrast it to those evoked by electrical stimulation, issues of considerable future interest.

Background: Advances in optogenetics have led to first reports of expression of light-gated ion-channels in non-human primates (NHPs). However, a major obstacle preventing effective application of optogenetics in NHPs and translation to optogenetic therapeutics is the absence of compatible multifunction optoelectronic probes for (1) precision light delivery, (2) low-interference electrophysiology, (3) protein fluorescence detection, and (4) repeated insertion with minimal brain trauma., New Method: Here we describe a novel brain probe device, a "coaxial optrode", designed to minimize brain tissue damage while microfabricated to perform simultaneous electrophysiology, light delivery and fluorescence measurements in the NHP brain. The device consists of a tapered, gold-coated optical fiber inserted in a polyamide tube. A portion of the gold coating is exposed at the fiber tip to allow electrophysiological recordings in addition to light delivery/collection at the tip., Results: Coaxial optrode performance was demonstrated by experiments in rodents and NHPs, and characterized by computational models. The device mapped opsin expression in the brain and achieved precisely targeted optical stimulation and electrophysiology with minimal cortical damage., Comparison With Existing Methods: Overall, combined electrical, optical and mechanical features of the coaxial optrode allowed a performance for NHP studies which was not possible with previously existing devices., Conclusions: Coaxial optrode is currently being used in two NHP laboratories as a major tool to study brain function by inducing light modulated neural activity and behavior. By virtue of its design, the coaxial optrode can be extended for use as a chronic implant and multisite neural stimulation/recording., (Copyright © 2013 Elsevier B.V. All rights reserved.)

Recording of identified neuronal network activity using genetically encoded calcium indicators (GECIs) requires labeling that is cell type-specific and bright enough for the detection of functional signals. However, specificity and strong expression are often not achievable using the same promoter. Here we present a combinatorial approach for targeted expression and single-cell-level quantification in which a weak promoter is used to drive trans-amplification under a strong general promoter. We demonstrated this approach using recombinant adeno-associated viruses (rAAVs) to deliver the sequence of the GECI D3cpv in the mouse cerebellar cortex. Direct expression under the human synapsin promoter (hSYN) led to high levels of expression (50-100 μM) in five interneuron types of the cerebellar cortex but not in Purkinje cells (PCs) (≤10 μM), yielding sufficient contrast to allow functional signals to be recorded from somata and processes in awake animals using two-photon microscopy. When the hSYN promoter was used to drive expression of the tetracycline transactivator (tTA), a second rAAV containing the bidirectional TET promoter (P(tet)bi) could drive strong D3cpv expression in PCs (10-300 μM), enough to allow reliable complex spike detection in the dendritic arbor. An amplified approach should be of use in monitoring neural processing in selected cell types and boosting expression of optogenetic probes. Additionally, we overcome cell toxicity associated with rAAV injection and/or local GECI overexpression by combining the virus injection with systemic pre-injection of hyperosmotic D-mannitol, and by this double the time window for functional imaging.

Studying brain function and its local circuit dynamics requires neural interfaces that can record and stimulate the brain with high spatiotemporal resolution. Optogenetics, a technique that genetically targets specific neurons to express light-sensitive channel proteins, provides the capability to control central nervous system neuronal activity in mammals with millisecond time precision. This technique enables precise optical stimulation of neurons and simultaneous monitoring of neural response by electrophysiological means, both in the vicinity of and distant to the stimulation site. We previously demonstrated, in vitro, the dual capability (optical delivery and electrical recording) while testing a novel hybrid device (optrode-MEA), which incorporates a tapered coaxial optical electrode (optrode) and a 100 element microelectrode array (MEA). Here we report a fully chronic implant of a new version of this device in ChR2-expressing rats, and demonstrate its use in freely moving animals over periods up to 8 months. In its present configuration, we show the device delivering optical excitation to a single cortical site while mapping the neural response from the surrounding 30 channels of the 6 × 6 element MEA, thereby enabling recording of optically modulated single-unit and local field potential activity across several millimeters of the neocortical landscape.

Excitatory drive enters the cerebellum via mossy fibers, which activate granule cells, and climbing fibers, which activate Purkinje cell dendrites. Until now, the coordinated regulation of these pathways has gone unmonitored in spatially resolved neuronal ensembles, especially in awake animals. We imaged cerebellar activity using functional two-photon microscopy and extracellular recording in awake mice locomoting on an air-cushioned spherical treadmill. We recorded from putative granule cells, molecular layer interneurons, and Purkinje cell dendrites in zone A of lobule IV/V, representing sensation and movement from trunk and limbs. Locomotion was associated with widespread increased activity in granule cells and interneurons, consistent with an increase in mossy fiber drive. At the same time, dendrites of different Purkinje cells showed increased co-activation, reflecting increased synchrony of climbing fiber activity. In resting animals, aversive stimuli triggered increased activity in granule cells and interneurons, as well as increased Purkinje cell co-activation that was strongest for neighboring dendrites and decreased smoothly as a function of mediolateral distance. In contrast with anesthetized recordings, no 1-10 Hz oscillations in climbing fiber activity were evident. Once locomotion began, responses to external stimuli in all three cell types were strongly suppressed. Thus climbing and mossy fiber representations can shift together within a fraction of a second, reflecting in turn either movement-associated activity or external stimuli.

Primary pancreatic lymphoma (PPL) is a rare tumor that usually presents with the clinical picture of advanced adenocarcinoma but has a much better prognosis. A 38-year-old man was referred after percutaneous transhepatic external biliary drainage for obstructive jaundice. Abdominal magnetic resonance imaging (MRI) and magnetic resonance cholangiopancreatography had revealed a 5-cm pancreatic head mass that caused biliary tract dilation. Computed tomography angiography showed that the mass encased the celiac trunk as well as the common hepatic and splenic arteries. MRI also revealed a metastatic lesion at the third lumbar vertebra. Serum carcinoembryonic antigen and carbohydrate antigen 19-9 levels were within normal range. The initial diagnosis was inoperable pancreatic adenocarcinoma; however, Tru-Cut pancreatic biopsy showed a large B cell lymphoma. After 6 sessions of chemotherapy and 21 sessions of radiotherapy, both the pancreatic mass and the vertebral metastasis had disappeared. However, he had persistent distal common bile duct stricture that could not be negotiated by either the endoscopic or percutaneous route. A Roux-en-Y hepaticojejunostomy was performed. The patient stayed alive without recurrence for 52 months after the initial diagnosis and 45 months after completion of oncologic treatment. In conclusion, a large pancreatic mass with grossly involved peripancreatic lymph nodes, without ascites, liver or splenic metastasis, should alert the clinician to the possibility of PPL. Cure is possible by chemoradiotherapy even in the presence of vertebral metastasis. Persistent stricture in the distal common bile duct may require a biliodigestive anastomosis.

Background/aims: We aimed in this study to investigate pre- and posttransplant clinical and psychosocial features of the donors and the effects of living-related liver transplantation and possible relevant factors on psychosocial outcome and family functioning., Methods: Thirty-two living donors (19 females, age 31.84 ± 7.10 years) were evaluated. Medical records of donors regarding pre- and posttransplant clinical and psychological features and family life were evaluated., Results: The donors were parents (n=28, 87.6%) in most. In the pretransplant evaluation, 5 donors (19.3%) had anxiety regarding postoperative complications and quality of life. Donors were discharged from the hospital in a median of 7 days (range, 5-30 days). Return to work and feeling of complete well-being were accomplished in a median of 4 weeks (range, 1-32 weeks) and 10 weeks (range, 4-48 weeks), respectively. Sixteen recipients (50.0%) suffered from major complications, and 3 (9.4%) required invasive intervention. Fourteen donors (43.4%) reported pain around the surgical incision and nonspecific gastrointestinal problems postoperatively. Psychological problems were observed in 8 donors (25.0%); 2 (6.3%) had depression requiring drug and psychotherapeutic intervention. Psychological disruption was found to be correlated with the presence of problems in the recipient (p<0.01, r=0.487). The donors' relationship with the recipient was negatively affected in 1 (3.1%), but improved in 15 (46.9%) cases. Nine donors (34.6%) displayed nervous behavior toward their spouses, and 2 (7.7%) later divorced. Life of the other family members was negatively affected in 8 (30.7%). Two donors' spouses (7.7%) failed to carry out domestic responsibilities., Conclusions: Psychological disturbance and abnormal family functioning are frequently observed during the posttransplant period. Therefore, psychologic assessment and evaluation of family functioning should be regularly repeated during the posttransplant period.

Aim: To investigate the eligible management of the cystic neoplasms of the liver., Methods: The charts of 9 patients who underwent surgery for intrahepatic biliary cystic liver neoplasms between 2003 and 2008 were reviewed retrospectively. Informed consent was obtained from the patients and approval was obtained from the designated review board of the institution., Results: All patients were female with a median (range) age of 49 (27-60 years). The most frequent symptom was abdominal pain in 6 of the patients. Four patients had undergone previous laparotomy (with other diagnoses) which resulted in incomplete surgery or recurrences. Liver resection (n = 6) or enucleation (n = 3) was performed. The final diagnosis was intrahepatic biliary cystadenoma in 8 patients and cystadenocarcinoma in 1 patient. All symptoms resolved after surgery. There has been no recurrence during a median (range) 31 (7-72) mo of follow up., Conclusion: In spite of the improvement in imaging modalities and increasing recognition of biliary cystadenoma and cystadenocarcinoma, accurate preoperative diagnosis may be difficult. Complete surgical removal (liver resection or enucleation) of these lesions yields satisfying long-term results.

Methods on rendering neurons in the central nervous system to be light responsive has led to a boom in using optical neuromodulation as a new approach for controlling brain states and understanding neural circuits. In addition to the developing versatility to "optogenetically" labeling of neural cells and their subtypes by microbiological methods, parallel efforts are under way to design and implement optoelectronic devices to achieve simultaneous optical neuromodulation and electrophysiological recording with high spatial and temporal resolution. Such new device-based technologies need to be developed for full exploitation of the promise of optogenetics. In this paper we present single- and multi-element optoelectronic devices developed in our laboratories. The single-unit element, namely the coaxial optrode, was utilized to characterize the neural responses in optogenetically modified rodent and primate models. Furthermore, the multi-element device, integrating the optrode with a 6×6 microelectrode array, was used to characterize the spatiotemporal spread of neural activity in response to single-site optical stimulation in freely moving rats. We suggest that the particular approaches we employed can lead to the emergence of methods where spatio-temporal optical modulation is integrated with real-time read out from neural populations.

OGTT was performed in 28 liver transplants maintained with tacrolimus to investigate carbohydrate metabolism and assess risk factors for development of PTDM. None had PTDM that was detected by OGTT. Early PTDM in four cases (14.3%) resolved in follow-up. Five new cases (17.9%) demonstrated DCM (DCM = IGT +/- hyperinsulinemia). Fasting measurements were normal in two hyperinsulinemic cases. With one (20%, p > 0.05) exception none of the children with DCM were overweight or had a family history of diabetes. All five (100%) children with DCM had been given high cumulative dosage of steroids 18 (78.3%)--without DCM (p > 0.05). The median age of children with DCM was greater [4.3 (12.7-18.0) vs. 7.0 (2.3-18.0) yr, p < 0.01] and duration of follow-up longer [5.3 (2.3-7.0) vs. 2.5 (0.7-7.3) yr, p < 0.05]. Four children (80%) with DCM were pubertal (p < 0.05). However, neither age nor duration of follow-up or pubertal stage had significant effect on DCM development. Early PTDM is a transient phenomenon and is not predictive for future development of diabetes. DCM is frequently observed in liver transplanted children. Albeit the children with DCM were given high cumulative dose of steroids, were older, mostly were pubertal, and had longer duration of follow-up, we cannot draw firm conclusions on effects of the risk factors on carbohydrate metabolism because of the small sample size and relatively short duration of follow-up. Unlike fasting measurements, OGTT can detect all children with DCM.

The inferior olive projects climbing fiber axons to cerebellar Purkinje neurons, where they trigger calcium-based dendritic spikes. These responses dynamically shape the immediate spike output of Purkinje cells as well as provide an instructive signal to guide long-term plasticity. Climbing fibers typically fire approximately once a second, and the instructive role is distributed over many such firing events. However, transmission of salient information on an immediate basis needs to occur on a shorter timescale during which a Purkinje cell would typically be activated by a climbing fiber only once. Here we show using in vivo calcium imaging in anesthetized mice and rats that sensory events are rapidly and reliably represented by momentary, simultaneous coactivation of microbands of adjacent Purkinje cells. Microbands were sagittally oriented and spanned up to 100 microm mediolaterally, representing hundreds of Purkinje cells distributed over multiple folia. Spontaneous and sensory-evoked microbands followed boundaries that were close or identical to one another and were desynchronized by olivary injection of the gap junction blocker mefloquine, indicating that excitation to the olive is converted to synchronized firing by electrical coupling. One-time activation of microbands could distinguish a sensory response from spontaneous activity with up to 98% accuracy. Given the anatomy of the olivocerebellar system, microband synchrony may shape the output of neurons in the cerebellar nuclei either via powerful inhibition by Purkinje cells or by direct monosynaptic excitation from the inferior olive.

The aim of the present study was to investigate whether high fat consumption changes the effects of stress on both motor activity performance, striatal and cortical dopamine and serotonin metabolites in rats. The animals were fed either with high fat or standard diet for 4 weeks. Restraint stress lasting for 15 min at +4 degrees C was applied daily to stress-exposed groups. Motor activity performance was measured weekly by using motor activity monitoring systems. At the end of the study, homovanillic acid (HVA) and 5-hydroxyindoleacetic acid (5-HIAA) levels of the striatum and cerebral cortex were measured by HPLCEC. It was observed that restraint stress increased locomotor activity and high-fat diet prevented this effect. Stress and high-fat intake had an additive decreasing effect on striatal HVA levels. 5-HIAA levels, on the other hand, were lower in both high fat and high fat + stress groups compared to the stress group. These results suggest that high-fat intake differentially affected the stress response on striatal dopaminergic and serotonergic neurons in rat brain regions studied and this may be related to the effects observed in motor activity performance.

A patient who developed necrotizing pancreatitis after transcatheter arterial chemoembolization (TACE) for hepatocellular carcinoma (HCC) is presented. A 55- year-old man had been followed for chronic hepatitis B infection for 10 years at another institution. He presented with multiple masses in the right lobe of the liver and a metastasis in the left adrenal gland. He was referred after a percutaneous liver biopsy which revealed a moderately differentiated HCC. He was treated by TACE. At the third session of TACE, the right hepatic artery was found to be thrombosed; however, angiography also demonstrated collateral feeder vessels (arising from the pancreaticoduodenal artery) which were used for treatment. He developed necrotizing pancreatitis, possibly due to regurgitation of the chemotherapeutic agents to the pancreas. He recovered without complications with imipenem-cilastatin prophylaxis. Acute pancreatitis is a rare but severe complication of TACE. Selective catheterization of the tumor vessels is the established standard in TACE. A careful risk-benefit analysis is mandatory in patients with abnormal collateral vessels. Treatment of acute necrotizing pancreatitis (ANP) after TACE is the same as the accepted approach to ANP due to other causes.

In vivo multiphoton fluorescence microscopy allows imaging of cellular structures in brain tissue to depths of hundreds of micrometers and, when combined with the use of activity-dependent indicator dyes, opens the possibility of observing intact, functioning neural circuitry. We have developed tools for analyzing in vivo multiphoton data sets to identify responding structures and events in single cells as well as patterns of activity within the neural ensemble. Data were analyzed from populations of cerebellar Purkinje cell dendrites, which generate calcium-based complex action potentials. For image segmentation, active dendrites were identified using a correlation-based method to group covarying pixels. Firing events were extracted from dendritic fluorescence signals with a 95% detection rate and an 8% false-positive rate. Because an event that begins in one movie frame is sometimes not detected until the next frame, detection delays were compensated using a likelihood-based correction procedure. To identify groups of dendrites that tended to fire synchronously, a k-means-based procedure was developed to analyze pairwise correlations across the population. Because repeated runs of k-means often generated dissimilar clusterings, the runs were combined to determine a consensus cluster number and composition. This procedure, termed meta-k-means, gave clusterings as good as individual runs of k-means, was independent of random initial seeding, and allowed the exclusion of outliers. Our methods should be generally useful for analyzing multicellular activity recordings in a variety of brain structures.

Aims: Histological subtyping of periampullary carcinomas is considered as a criterion for prognosis and therapeutic implications of these tumours. We assessed the immunoexpression rates of HepPar-1, CDX2 and MUC2 antibodies in different subtypes of periampullary adenocarcinomas (PAC), intestinal and pancreatobiliary, in order to assess their impact on differential diagnosis of this group of cancers. The expression of antibodies was also measured in ductal adenocarcinoma of the pancreatic head (DAPH)., Methods: Sixty-five patients with PAC and DAPH who underwent pancreatic Whipple resection constituted the study cohort. Of these, 46 (71%) had PAC, and 19 (29%) had DAPH. Among PACs, 20 (44%) were intestinal and 26 (56%) were pancreatobiliary type., Results: HepPar-1 immunoreactivity was detected in 18 (39%) of all PACs. The rate of HepPar-1 expression was significantly higher in intestinal type PAC (75%) than it was in pancreatobiliary type (12%). The sensitivity, specificity, and accuracy of HepPar-1 immunoexpression for diagnosing intestinal type PAC were 75% , 89%, and 83%, respectively. Similarly, the rates of both CDX2 and MUC2 expressions were significantly higher in intestinal type PAC (80%) than they were in pancreatobiliary type (8%). The sensitivity, specificity, and accuracy of both CDX2 and MUC2 immunoexpressions for intestinal type PAC were 80%, 92%, and 87%, respectively., Conclusion: HepPar-1 antibody was found to be a highly sensitive and specific marker for distinguishing intestinal type from pancreatobiliary type among PACs. In addition to CDX2 and MUC2 antibodies, HepPar-1 immunoexpression seems to have a potential role in differential diagnosis of PACs.

We report our success with somatostatin and propranolol to treat small-for-size syndrome that occurred despite splenic artery ligation. A 48-year-old woman with cirrhosis due to autoimmune hepatitis underwent living-donor liver transplant; her graft-to-body weight ratio of the right lobe was 0.91%. After arterial reperfusion, portal pressure and flow were 24 cm H20 and 2.22 L/min (ie, 360 mL/100g graft/min), respectively. Following splenic artery ligation, the portal pressure decreased to 16 cm H20 and portal flow to 1.74 L/min (ie, 282 mL/100g graft/min). On the second postoperative day, small-for-size syndrome was diagnosed based on the marked prolongation of prothrombin time (international normalized ratio, 4.4), hyperbilirubinemia (359.1 micromol/L), rapid escalation of transaminases (alanine aminotransferase 2488 U/L, aspartate aminotransferase 1075 U/L) and very high portal flow rate (> 90 cm/sec). Oral propranolol (40 mg/day b.i.d.) and somatostatin infusion (250-microgram bolus followed by perfusion at a rate of 250 microgram/h for 5 days) were started. Prothrombin time and transaminase levels began to decrease the following day, although the bilirubin level increased to 495.9 micromol/L before returning to normal. The patient was discharged in excellent health 5 weeks after surgery. Despite reduction of portal pressure by splenic artery ligation, small-for-size syndrome may develop in patients with persistent high portal flow. To the best of our knowledge, this is the first report of the successful treatment of small-for-size syndrome by somatostatin and propranolol in the clinical setting.

A 64-year-old woman with upper abdominal pain, nausea, and vomiting was admitted. The magnetic resonance imaging revealed marked dilation and "crowding" of the segment 4 bile ducts with an area suspicious for a stone or tumor. Ultrasonography-guided percutaneous transhepatic cholangiography revealed multiple filling defects in the segment 4 bile ducts, the left and common hepatic ducts. A left hepatectomy and cholecystectomy was performed. Dilated bile ducts containing mucinous material and a mass in the cystically dilated bile ducts of segment 4 were detected in the gross examination. It showed continuity within the surrounding dilated bile ducts. The dilated bile ducts of the segments 2 and 3 contained mucinous material without any apparent mass formation. Microscopically, the bile ducts were lined by biliary epithelium displaying simple and complex papillary structures with moderate to severe degree of dysplastic changes. The mass was composed of complex papillary structures filling the bile duct with a few foci of invasion. The papillary structures were composed of mucin-producing columnar cells as well as cells with oncocytic appearance. Patchy cytokeratin 7, cytokeratin 19, hepatocyte paraffin 1, MUC2, and CDX2 immunopositivities were observed. Biliary papillomatosis, mucin-producing intrahepatic cholangiocarcinoma, and intraductal papillary-type peripheral cholangiocarcinoma are in the same disease spectrum of papillary biliary neoplasm and termed as intraductal papillary neoplasm of the liver. Mucinous hypersecretion and signs of mucobilia are considered specific and should raise the suspicion of lesions in this spectrum.

An 11-month-old female infant underwent living-donor liver transplantation for secondary biliary cirrhosis 8 months after Kasai operation. The portal vein was hypoplastic, and its diameter was only 4 mm at the level of the splenomesenteric confluence. End-to-end anastomosis of the recipient suprarenal vena cava to the graft portal vein (a left lateral section from the patient's mother) was performed. An end-to-side portocaval shunt with the recipient portal vein was constructed to mitigate portal hypertension. The early postoperative course was relatively uneventful. However, persistent hepatitis caused by infection with Cytomegalovirus and chronic rejection resulted in progressive hepatic dysfunction. Nine months after the initial operation, a living-donor retransplantation (a left lateral section from the patient's grandmother) was performed. One month after retransplantation, severe acute rejection that eventually required OKT3 treatment developed. The patient was in excellent health until 4 months after retransplantation, when another acute rejection episode (for which she was successfully treated) developed. Cavoportal hemitransposition should be included in the armamentarium of the transplant surgeon for the management of extensive portal system thrombosis and portal vein hypoplasia. An additional shunt may be useful in mitigating portal hypertension.

Major bile duct injury during cholecystectomy represents potentially severe complications with unpredictable long-term results. If these lesions are not treated adequately, they can lead to hepatic failure or secondary biliary cirrhosis therefore requiring liver transplantation. We report a patient who required liver transplantation 15 years after open cholecystectomy. A l0-year old girl underwent open cholecystectomy and duodenal repair for cholelithiasis and cholecystoduodenal fistula. She required two surgical interventions, hepaticojejunostomy which was performed in another center and portoenterostomy for biliary stricture at our institution seven years after the cholecystectomy. Eight years after the third operation, she required recurrent hospitalization for treatment of hepatic abscesses. The extremely short intervals between the three life threatening episodes and the rapid progression to severe sepsis were taken into consideration and liver transplantation was performed at the age of 25. She is leading a healthy life at 4 years post transplantation. Although iatrogenic biliary injury can usually be treated successfully by a combination of surgery, radiological and endoscopic techniques, patients with severe injuries develop irreversible liver disease. This case report and review of the literature suggest that liver transplantation is a treatment modality for a selected group of patients with end-stage liver disease secondary to bile duct injury.

Obstruction of a major hepatic vein, or major portal vein, or biliary tree branch causes atrophy of the related hepatic region, and frequently, hypertrophy in the remaining liver-the atrophy-hypertrophy complex (AHC). Whether hydatid cysts can cause AHC is controversial. The records of 370 patients who underwent surgery for hepatic hydatid disease between August 1993 and July 2002 were evaluated retrospectively. Excluding six patients with previous interventions on the liver, AHC had been recorded in the operative notes of 16 patients (4.4%); for all patients, a cyst located in the right hemiliver had caused atrophy of the right hemiliver and compensatory hypertrophy of the left hemiliver. The computed tomography images of seven patients were suitable for volumetric analysis. The median (range) right and left hemiliver volumes were 334 (0-686) ml and 1084 (663-1339) ml, respectively. The median (range) cyst volume was 392 (70-1363) ml. AHC due to Echinococcus granulosus was confirmed by objective volumetric analysis. The presence of AHC should alert the surgeon to two implications. First, pericystectomy may be hazardous due to association with major vascular and biliary structures. Second, in patients with AHC, the hepatoduodenal ligament rotates around its axis; this should be considered to avoid vascular injury if a common bile duct exploration is to be performed.

A 55-year-old man was investigated for right upper abdominal quadrant pain. He had no history of abdominal trauma or surgery. Imaging studies showed a common hepatic artery aneurysm involving the gastroduodenal artery. Following aneurysmectomy, examination with a hand Doppler apparatus yielded clear arterial signals from the liver surface. Therefore, vascular reconstruction was not performed. He had an uneventful postoperative course.

A foreign body is a rare cause of obstructive jaundice. We report a 19-year-old woman with jaundice caused by a surgical gauze in the common bile duct (CBD). Four yours earlier, she had undergone a cholecystectomy and drainage for hydatid disease of the liver. Her postoperative course was complicated by a biliary fistula that healed after 50 days. She now presented with obstructive jaundice of 2 weeks' duration. Magnetic resonance cholangiopancreatography (MRCP) showed a signal-void mass, consistent with a CBD stone. Surgical exploration of the CBD revealed a surgical gauze as the cause of the obstruction. To the best of our knowledge, this is the first case of a surgical gauze obstructing the CBD requiring surgical removal.

Background: Iatrogenic factors became the leading mechanisms of severe cholangitis in a referral center., Patients and Methods: The records of the 58 patients treated for severe cholangitis between 1996 and May 2004 (inclusive) were evaluated., Results: The most frequent underlying diseases were periampullary tumors and mid-bile duct carcinomas (22), followed by proximal cholangiocarcinomas (14). The triggering mechanism was an incomplete endoscopic retrograde cholangiopancreatography (ERCP) in 32 patients, incomplete or inappropriate percutaneous transhepatic biliary drainage (PTBD) in 6, apparently successful ERCP and stenting in 1, and percutaneous transhepatic cholangiography in 1. PTBD was the treatment of choice (38). Mortality was 29% (17/58); the major causes were refractory sepsis (8) and incomplete biliary drainage (advanced tumor, technical failure, or hemobilia) (8)., Conclusions: In this series composed predominantly of patients referred after development of sepsis, ERCP and PTBD complications were the leading mechanisms of severe cholangitis. Nonoperative biliary manipulations are invasive procedures with potentially fatal complications. The decisions to perform such procedures and periprocedural management are responsibilities of an experienced multidisciplinary team.

Background: Autoimmune pancreatitis is an evolving entity., Methods: A patient who had spontaneous regression of a pancreatic head mass and biliary obstruction due to autoimmune pancreatitis is presented., Results: A 58-year-old diabetic woman with jaundice was referred for pancreatic head carcinoma diagnosed by magnetic resonance imaging (MRI). At laparotomy, a pancreatic head mass (4 x 3 cm) that involved the transverse mesocolon and two other hard masses (1 cm) in the pancreatic body and tail were found. The gallbladder was palpated as a hard tumor mass. Frozen section examination of the gallbladder and pancreatic biopsies revealed cholecystitis and pancreatitis with lymphoplasmacytic infiltration. The common bile duct was brittle and unsuitable for anastomosis. Starting 1 month after the operation, drainage from the biliary catheter decreased gradually and stopped. There was no parenchymal lesion on MRI examination in the 2nd postoperative month. Cholangiography from the percutaneous catheter showed flow of contrast agent into the duodenum. Serum immunoglobulin G, G4 and E levels were increased., Conclusion: To the best of our knowledge, this is the first report of spontaneous regression of a pancreatic head mass and biliary obstruction due to autoimmune pancreatitis.

Interaction between an electronic and a biological circuit has been investigated for a pair of electrically connected nonlinear oscillators, with a spontaneously oscillating olivary neuron as the single-cell biological element. By varying the coupling strength between the oscillators, we observe a range of behaviors predicted by model calculations, including a reversible low-energy dissipation "amplitude death" where the oscillations in the coupled system cease entirely.

Background: We presented our experience with definitive treatment of traumatic biliary injuries., Methods: Six male patients (mean age 13 years; range 2 to 32 years) who were referred to our unit for definitive treatment of traumatic biliary injuries were retrospectively evaluated. Data were analyzed in terms of demographic characteristics, mechanisms of injuries, associated injuries, previous treatments, symptoms on admission, treatment at our unit, and the results of treatment. Outcome was assessed using modified Schweiser and Blumgart criteria., Results: The injuries were due to blunt abdominal trauma in all the patients but one who had a gunshot wound. In three patients, biliary injuries were missed at the initial operation. On admission, three patients had external biliary fistulas, two had biliary strictures. One patient was sent following inadvertent ligation of the hepatoduodenal ligament during attempts to control hemorrhage. Roux-en-Y hepaticojejunostomy was performed in three patients. Percutaneous biloma drainage was performed in two patients, resulting in fistula closure in 13 and 40 days, respectively. One patient was treated by endoscopic retrograde cholangiopancreatography and papillotomy, which enabled fistula closure in three days. One patient was lost to follow-up. One patient died from hepatic failure 11 years after the trauma. At the end of a mean follow-up of 49 months (range 15 to 75 months), three patients were in excellent condition, while one patient experienced occasional attacks of cholangitis., Conclusion: In patients with undetected biliary injuries and in those with unsuccessful repair attempts, biliary reconstruction should be performed in experienced hepatopancreatobiliary surgery units.

We have designed, fabricated, and characterized a microminiaturized "neuroport" for brain implantable neuroprosthesis applications, using an analog CMOS integrated circuit and a silicon based microelectrode array. An ultra-low power, low-noise CMOS preamplifier array with integral multiplexing was designed to accommodate stringent thermal and electrophysiological requirements for implantation in the brain, and a hybrid integration approach was developed to fabricate a functional microminiaturized neuroprobe device. Measurements showed that our fully scalable 16-channel CMOS amplifier chip had an average gain of 44 dB, bandwidth from 10 Hz to 7.3 kHz, and an equivalent input noise of approximately 9 microVrms with an average power consumption per preamplifier of 52 microW, which is consistent with simulation results. As a proof-of-concept demonstration, we have measured local field potentials from thalamocortical brain slices of rats, showing oscillatory behavior with an amplitude about 0.5 mV and a period ranging 80-120 ms. The results suggest that the hybrid integrated neuroport can form a prime platform for the development of a next level microminiaturized neural interface to the brain in a single implantable unit.

We demonstrate a proof-of-concept optical spectroscopic system for bioaerosol-particle fluorescence detection, in which a pulsed high-power laser is replaced by a highly compact linear array of sequentially fired light from blue light-emitting diodes. The results suggest that low-cost, compact optical aerosol detection may be feasible with the contemporary emergence of efficient UV light-emitting diodes.

Background and Aims: To evaluate treatment results in iatrogenic biliary injuries with concomitant vascular injuries., Patients/methods: Between January 1998 and May 2002 (inclusive), angiography was performed in 45 of the 105 patients treated for iatrogenic biliary tract injury. The charts of these 45 patients and 5 other patients in whom vascular injury was diagnosed at operation were evaluated retrospectively. Twenty-nine patients had concomitant vascular injury, the biliovascular injury group (BVI), and the remaining 21 patients had isolated biliary tract injury (IBTI)., Results: The most frequent initial operation was a cholecystectomy. The frequency of high-level (Bismuth III or IV) strictures was 90% in the BVI group and 62% in the IBTI group ( P<0.05). Perioperative mortality was 7% in the BVI group and 5% in the IBTI group ( P>0.05). The morbidity in the BVI group was significantly higher ( P<0.05). Two patients in each group were lost to follow up. During a median (range) follow up of 31 months (5-51 months), a successful functional outcome was achieved in 96% of the BVI group and 100% of the IBTI group with a multimodal approach ( P>0.05)., Conclusions: The frequency of high-level biliary injury and morbidity were significantly higher in the BVI group. However, concomitant vascular injury had no significant effect on mortality and medium-term outcome of biliary reconstruction. Thus, routine preoperative angiography is not recommended.

We evaluated the usefulness and limitations of endoscopic ultrasonography (EUS) in pancreatic mass lesions. EUS was useful in detecting small pancreatic mass lesions, especially ductal adenocarcinomas smaller than 20 mm and small islet cell tumors smaller than 10 mm. In some of these cases, characteristic echo patterns were specific and useful for differential diagnosis from focal pancreatitis. However, when EUS did not clearly delineate a tumor at the stenotic area of the main pancreatic duct, transpapillary pancreatoscopy and biopsy/cytology were sometimes effective to obtain a definitive diagnosis. EUS fine-needle aspiration should be performed in conjunction with imaging modalities when the differential diagnosis of a pancreatic mass is difficult to make. Although the value of EUS in cancer staging was overestimated, EUS in conjunction with spiral computed tomography or magnetic resonance imaging should be performed for such a purpose. Usefulness and limitations of intraductal ultrasonography (IDUS) also were evaluated. IDUS was useful in detecting carcinoma in situ and small tumors and in assessing parenchymal invasion and the intraductal spread of the tumor. IDUS was also useful in accurately localizing islet cell tumor and in differentiating benign from malignant cases of localized stenosis of the main pancreatic duct. Thus, EUS and IDUS are indispensable modalities in the diagnosis of pancreatic diseases.

Background: Radical resection is the only potentially curative treatment for hepatic alveolar echinococcosis (AE). Although Turkey is an endemic region, population screening is not performed and early diagnosis is rare. Consequently, surgeons are compelled to explore possibilities such as near-total resection and biliodigestive anastomosis for palliation of jaundice., Methods: Surgery was performed in 32 patients with hepatic AE with the following indications: (1) resection; (2) palliation of jaundice; (3) definite assessment of operability; (4) failure in the management of cavity infection by percutaneous methods. Curative resection (R0 = complete resection of all parasitic mass [n = 9], and R1 = a resection in which a small remnant was left on a vital structure [n = 8]) were performed in 17 patients, intrahepatic cholangiojejunostomy in 7, laparotomy-external drainage in 7, and debulking in 1., Results: Perioperative mortality rates were 2/17, 0/7, 2/7 and 1/1, respectively. Twelve patients in the curative resection group are alive without recurrence/progression of the small remnant during a median follow-up of 59 (range 27-116) months. One patient developed an inoperable recurrence that was treated with albendazole. One patient was lost to follow-up. Long-term albendazole treatment was effective in all R1 patients except a patient who had slow asymptomatic progression. Successful palliation of jaundice was achieved in 5 of the 7 intrahepatic cholangiojejunostomy patients., Conclusions: The results of R1 resection in alveolar hydatid disease are similar to those of R0 resection; a small remnant is successfully controlled by albendazole. In patients with jaundice due to hilar invasion, biliary diversion from segment 3 or 5 is effective for palliation of the jaundice and facilitates albendazole treatment., (Copyright 2003 S. Karger AG, Basel)