Efficient assembly of multi-color fiberless optoelectrodes with on-board light sources for neural stimulation and recording.

Fiberless optoelectrodes are an emerging tool to enable brain circuit mapping by providing precise optical modulation and electrical monitoring of many neurons. While optoelectrodes having an on-board light source offer compact and optically efficient device solutions, many of them fail to provide robust thermal and electrical design to fully exploit the recording capabilities of the device. In this work, we present a novel fiberless multicolor optoelectrode solution, which meets the optical and thermal design requirements of an in vivo neural optoelectrode and offers potential for low-noise neural recording. The total optical loss measured for 405 nm and 635 nm wavelengths through the waveguide is 11.7±1.1 dB and 9.9±0.7 dB, corresponding to respective irradiances of 1928 mW/mm2 and 2905 mW/mm2 at the waveguide tip from 6 mW laser diode chips. The efficient thermal packaging enables continuous device operation for up to 190 seconds at 10% duty cycle. We validated the fully packaged device in the intact brain of anesthetized mice co-expressing Channelrhodopsin-2 and Archaerhodopsin in the hippocampal CA1 region and achieved activation and silencing of the same neurons. We discuss improvements made to reduce the stimulation artifact induced by applying currents to the laser diode chips.

Post-traumatic stress influences the brain even in the absence of symptoms: A systematic, quantitative meta-analysis of neuroimaging studies.

Stress affects brain function, and may lead to post-traumatic stress disorder (PTSD). Considerable empirical data for the neurobiology of PTSD has been derived from neuroimaging studies, although findings have proven inconsistent. We used an activation likelihood estimation analysis to explore differences in brain activity between adults with and without PTSD in response to affective stimuli. We separated studies by type of control group: trauma-exposed and trauma-naïve. This revealed distinct patterns of differences in functional activity. Compared to trauma-exposed controls, regions of the basal ganglia were differentially active in PTSD; whereas the comparison with trauma-naïve controls revealed differential involvement in the right anterior insula, precuneus, cingulate and orbitofrontal cortices known to be involved in emotional regulation. Changes in activity in the amygdala and parahippocampal cortex distinguished PTSD from both control groups. Results suggest that trauma has a measurable, enduring effect upon the functional dynamics of the brain, even in individuals who experience trauma but do not develop PTSD. These findings contribute to the understanding of whole-brain network activity following trauma, and its transition to clinical PTSD.

[Lymphoceles after radical retropubic prostatectomy. A treatment algorithm]. / Lymphozele nach radikaler retropubischer Prostatektomie. Ein Behandlungsalgorithmus.

Lymphoceles represent a common complication following pelvic lymphadenectomy and radical retropubic prostatectomy. Relevant articles published in the last 25 years and our own results based on a prospective study were taken as the basis for a treatment algorithm for lymphoceles after radical prostatectomy.The type of intervention depends on the clinical situation of the patient. Symptomatic lymphoceles can be managed initially by percutaneous aspiration with or without instillation of sclerosing agents. However, lymphocele recurrence rates are high. Symptomatic, sterile lymphoceles appear to be ideally suited for drainage by laparoscopic techniques. This method is effective, usually immediately definitive, results in minimal patient morbidity, and allows for a more rapid recovery. Infected lymphoceles require percutaneous or open surgical drainage. Laparoscopic marsupialization of symptomatic lymphoceles after pelvic lymphadenectomy for prostate cancer appears to be safe and effective. Because of the minimal postoperative morbidity, rapid convalescence, and low recurrence rate, laparoscopic lymphadenectomy should be considered as a first-line treatment for symptomatic, uninfected sterile lymphoceles.

Reducing inter-replicate variation in fourier transform infrared spectroscopy by extended multiplicative signal correction.

Fourier transform infrared (FT-IR) spectroscopy is a powerful tool for characterizing biological tissues and organisms, but it is plagued by replicate variation of various sources. Here, a method for estimating and correcting unwanted replicate variation in multivariate measurement signals, based on extended multiplicative signal correction (EMSC), is presented. Systematic patterns of unwanted methodological variations are estimated from replicate spectra, modeled by a linear subspace model, and implemented into EMSC. The method is applied to FT-IR spectra of two different sets of microorganisms (different double gene knockout strains of Saccharomyces cerevisiae and different species of Listeria) and compared to other preprocessing methods used in FT-IR absorption spectroscopy of microorganisms. The EMSC replicate correction turns out to perform best among the compared methods.

[The state of pediatric urological outpatient surgery]. / Stand der ambulant-operativen Kinderurologie.

Economic requirements and the wishes of the patients have led to a clear increase in outpatient surgery. Besides the observance of legal conditions, a well-devised structure of organization is the prerequisite for a frictionless realization. The operating surgeon decides about the suitability of the patient, is responsible for a course without complications and takes on the postoperative care. The most frequent operations are circumcision, orchidopexy and the repair of inguinal hernias. Outpatient surgery stands out for a low rate of complications and a high satisfaction of the patients.

[Errors and risks in ambulatory operations: circumcision]. / Fehler und Gefahren bei ambulanten Operationen: Zirkumzision.

As one of the most frequently performed operations circumcisions can entail not only typical but also rare complications with possibly fatal consequences. The following areas are of particular importance: legal aspects of the operation, indication for an operation, pre-operative information, post-operative surveillance and after-care. The amount of circumcisions carried out in different European countries vary widely. This shows a difference in indication assessment, which may suppose that a number of operations are not necessary.

Chemometric modelling based on 2D-fluorescence spectra without a calibration measurement.

MOTIVATION: 2D fluorescence spectra provide information from intracellular compounds. Fluorophores like trytophan, tyrosine and phenylalanin as well as NADH and flavins make the corresponding measurement systems very important for bioprocess supervision and control. The evaluation is usually based on chemometric modelling using for their calibration procedure off-line measurements of the desired process variables. Due to the data driven approach lots of off-line measurements are required. Here a methodology is presented, which enables to perform a calibration procedure of chemometric models without any further measurement. RESULTS: The necessary information for the calibration procedure is provided by means of the a priori knowledge about the process, i.e. a mathematical model, whose model parameters are estimated during the calibration procedure, as well as the fact that the substrate should be consumed at the end of the process run. The new methodology for chemometric calibration is applied for a batch cultivation of aerobically grown S. cerevisiae on the glucose Schatzmann medium. As will be presented the chemometric models, which are determined by this method, can be used for prediction during new process runs. AVAILABILITY: The MATHLAB routine is free available on request from the authors.

In-situ-fluorescence-probes: a useful tool for non-invasive bioprocess monitoring.

Optical sensors appear to be very promising for different applications in modern biotechnology. They offer the possibility to interface all the well known optical analysis techniques to bioprocesses via fiber optical cables. Thus, high sophisticated and sensitive optical analysis techniques can be coupled to a bioprocess via these light signal transporting fibers. A wide variety of sensor types for application in biotechnology has been described. Normally these sensors are non-invasive and the response times are nearly instantaneous. In particular, the use of glass fiber technology makes these sensors small, robust and reduces their costs.

Monitoring and control of industrial downstream processing of sugar beet molasses.

In present work the determination of several amino acids during the industrial chromatographic desugarisation of molasses is presented. The use of innovative biosensor systems for highly specific detection of serine is described. Using two-dimensional fluorescence spectrometry, a non-invasive method for the determination of several product fractions could be established in an industrial chromatographic procedure.

Laparoscopic hernioplasty versus conventional hernioplasty (Shouldice): results of a prospective randomized trial.

The results of our randomized trial of 176 patients comprising primary hernias [Shouldice versus transabdominal preperitoneal approach (TAPP)] showed only slight advantages for the laparoscopically operated group compared to the conventionally operated group: less subjective pain (significant only on fifth postoperative day, p < 0.05), reduced analgesic requirement (significant only on third postoperative day, p < 0.05), significantly shorter duration of hospitalization (4 days vs. 6 days, p < 0.05) and faster return to work (27 days vs. 34 days, NS). Regarding the incidence of recurrences, there was no significant difference between the groups (two recurrences vs. one recurrence) within a follow-up period of 2 years. Postoperative morbidity was similar and the total cost was less for the TAPP group.

Nerve irritation after laparoscopic hernia repair.

BACKGROUND: Between October 1992 and May 1996, 893 hernia repairs were performed at the Surgical Clinic in Mannheim: 448 (50%) using laparoscopy (TAPP-method) and 445 (50%) using the conventional anterior approach (Shouldice). MATERIALS AND METHODS: For this study, 723 (81%) of these repairs were followed up in a prospective trial of postoperative nerve irritations. RESULTS: The rate of nerve entrapment in the laparoscopic group was 4.2% (n = 19), and in the group that underwent conventional surgery 1.8% (n = 8). The genitofemoral nerve was affected with particularly high frequency (2%), and the ilioinguinal nerve and lateral cutaneous nerve of the thigh (LCNT) each was affected in 1.1% of the cases. CONCLUSIONS: Reduction in the number of clips used and careful attention to the anatomic nerve course during preparation and placement of mesh led to a significant reduction in the occurrence of nerve irritations. In the last 100 patients who underwent laparoscopic hernia repair, only one nerve lesion was seen.

Relation of neuropsychological and magnetic resonance findings in amyotrophic lateral sclerosis: evidence for subgroups.

The relationship between neuropsychological impairments and changes in cranial MR images was investigated in a group of 74 consecutive patients with the sporadic form of amyotrophic lateral sclerosis (ALS). Neuropsychological tests included measures of frontal lobe function, memory, intelligence, and attention. Compared with a control group, a significant impairment of the ALS group emerged for the areas of visual attention, inhibition of response alternatives, visual memory, and word generation. These neuropsychological impairments did not show a relation to clinical status of the patients. Likewise, MR parameters derived by computer assisted planimetric analysis showed a ventricular enlargement and parenchymal atrophy in the ALS group compared with age-matched controls. When ALS patients were assigned to two subgroups differing on the basis of the neuropsychological tests by cluster-analysis the cluster with the significant impairment also showed a pronounced change for the MR-parameters while the subgroup showed essentially normal neuropsychological performance. This pattern suggests that subgroups of ALS with differential impairment of neuropsychological functions can be defined.

[Open laparoscopic approach--an alterative to the Veress needle. Experiences after 1,000 laparoscopies]. / Der offene laparoskopische Zugang--Alternative zu der Veress-Nadel. Erfahrungen nach 1000 Laparoskopien.

A mini-laparotomy as described by Hasson was used in a modified way in 1000 laparoscopic procedures. In comparison with the insertion of a Veress needle we find the open approach to be a safer and quicker way of obtaining pneumoperitoneum.

Effects of joining peptide (1-18) and histamine on dehydroepiandrosterone (DHEA) and dehydroepiandrosterone sulphate (DHEAS) production of human adrenocortical cells in vitro.

Joining peptide 1-18 (JP 1-18), added alone in concentrations of 10(-13)-10(-7) M to collagenase-dispersed human adrenocortical cells, did not affect the basal production of corticosterone, cortisol, aldosterone, dehydroepiandrosterone (DHEA) and dehydroepiandrosterone sulphate (DHEAS). JP 1-18 potentiated the ACTH-stimulated production of steroids. When administered in combination with histamine (10(-8)-10(-3) M), JP 1-18 (10(-8) or 10(-10) M), enhanced the synthesis of DHEA and DHEAS. JP 1-18, together with histamine, may play a role in the regulation of DHEA and DHEAS production.

Molecular analysis of the structure of the maize B-chromosome.

The overall composition of the maize B is similar to that of the standard chromosome complement (A-chromosomes). This has been demonstrated by the use of several methods including: (a) genomic in situ hybridization (GISH), (b) analysis of highly repetitive sequences by the comparison of restriction digests of 0B and +B DNA and (c) the characterization of middle-repetitive cloned sequences. By the use of the technique of random amplification of polymorphic DNA-polymerase chain reaction, we have identified a B-specific repetitive sequence family. Sequence analysis of the B-specific clone reveals a relationship to the PREM-1 family of maize retroelements, which are preferentially transcribed in pollen. These results suggest an internal origin of the B-chromosome from within the maize genome, but demonstrate also that specific sequences can evolve by rapid processes of genomic turnover. Models for the origin of the maize B are discussed in the context of the present data.

[Results of colorectal carcinoma surgery in elderly patients]. / Ergebnisse der colorektalen Karzinomchirurgie des alten Patienten.

Between 1972 and 1995, 4434 operations for colorectal carcinoma were performed at the University Clinic of Mannheim. The increasing average age of the patients resulted in a higher lethality rate due to more emergency operations and concomitant failure of other organs. But the prognosis of patients over 70 years old can be compared with younger patients when hospital lethality is not considered. Thus the aim of treatment in older patients is also R0-resection, avoidance of emergency operations, optimum treatment of concomitant failure of other organs and multiple operations in extreme emergency cases.

Immunological and clinical response to immunosuppressive treatment in paraneoplastic cerebellar degeneration.

OBJECTIVE: To report the clinical and immunological response to immunosuppressive treatment with cyclophosphamide in two patients with paraneoplastic cerebellar degeneration. DESIGN: Case reports. Clinical and immunological follow-up data available for 4 1/2 years in the first patient and for 2 years in the second patient. SETTING: A 1500-bed university hospital and a 1200-bed university teaching hospital. INTERVENTION: Cyclophosphamide intermittent treatment. MAIN OUTCOME MEASURE: Clinical disability. RESULTS: One of the patients, who was treated from an early stage, recovered completely. The other patient showed a partial clinical response. While the two patients were receiving a maintenance regimen with cyclophosphamide, the conditions of both patients remained stable for at least 2 years. In both patients, intrathecal antibody synthesis declined considerably. CONCLUSION: Early induction of immunosuppressive therapy with cyclophosphamide should be tried in treating patients with paraneoplastic cerebellar degeneration.