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To investigate the structure–function correlation analysed by full-field electroretinography (ffERG) and optical coherence tomography (OCT) in typical and pericentral subtypes of retinitis pigmentosa (RP). A retrospective, cross-sectional, observational study of right eyes was conducted. The primary analysis used ffERG data to compare the RP subtypes. The subgroup analysis was used to correlate the structure, analysed by OCT, and function, determined by ffERG. Linear regressions explored the relationship between best-corrected visual acuity (BCVA) and multiple parameters. A total of 188 eyes were included. Amplitudes of responses of rod, rod-cone, cone, and 30 Hz flicker of typical type were lower than those of pericentral and other types. In the subgroup analysis, 41 and 21 eyes of the typical and pericentral types were studied, respectively. The correlation between the estimated preserved photoreceptor area and all ffERG amplitude parameters were significant in the typical type, but not in pericentral type. Old age, decreased intact ellipsoid zone length, typical type, and thin central retinal thickness were negatively correlated with BCVA. Typical type RP developed more extensive degeneration and poorer BCVA compared to others. Strong structure–function correlation was found in typical type while not in pericentral type. OCT may be a useful tool for monitoring RP status in typical type, providing useful parameters for the prediction of BCVA.

BackgroundTo explore the correlation between visual field (VF) defect values and retinal nerve fiber layer (RNFL) thickness for intracranial tumor and glaucoma patients.MethodsRetrospective analysis is performed for the intracranial and glaucoma patients, whose VF defect values were measured with Octopus perimeter cluster analysis, RNFL thickness, ganglion cell layer (GCL) thickness, and optic disk parameters measured with swept-source OCT. The differences between VF and RNFL (including the data of optic disc) are calculated. The correlation between VF defect values and RNFL and GCL thickness are explored.ResultsIn total 43 eyes of 29 patients with intracranial tumor and 31 eyes of 19 patients with glaucoma were enrolled. The thickness of RNFL not only for the whole (360°), but also for the four quadrants was thinner in the glaucoma group than those of the intracranial tumor group (p). There is no significant difference in VF for those two groups except glaucoma having lower sLV (pConclusionsIntracranial tumor has a weak correlation between the RNFL thickness and Octopus VF MD, compared with that of glaucoma. OCT and Octopus VF might provide more helpful information for the differential diagnosis of intracranial tumor and glaucoma.

Several influential philosophers and scientists have advanced a framework, often called Neo-Cartesianism (NC), according to which animal suffering is merely apparent. Drawing upon contemporary neur...

Supramolecular chirogenesis is one of the most rudimentary topics in the interdisciplinary sciences and essentially deals with various natural processes and innovative modern technologies. A comprehensive and rigorous understanding of such phenomenon is necessary to have a clear insight into the fundamental mechanisms and the various controlling factors, which would eventually lead to a range of practical applications of chiral supramolecular science. Metalloporphyrin tweezers have been extensively employed for such chirogenic processes due to their exciting physicochemical and tunable spectral properties, large stabilities, easily available synthetic protocols, and excellent abilities to form molecular assemblies. During the last few decades, various metalloporphyrin tweezers have been developed and considerably utilized by several research groups for assigning the absolute configuration to a variety of chiral diamines, conjugates of primary and secondary amines, amino alcohols, secondary alcohols, α-chiral carboxylic acids, etc. Our group has been at the forefront in trying to establish the structure-property correlation in this important area of interdisciplinary research. A brief account of our systematic investigation for understanding the underpinning mechanism of chirality induction and control at the molecular level over the last few years is presented in this Perspective article. The comprehensive understanding of such mechanistic details will be helpful in understanding various natural processes and designing modern technologies for various chirogenic functions in the fields of molecular sensors, nanotechnology, and supramolecular chemistry.

Lanthanides are routinely incorporated into quantum dots to act as down-shifting and up-converting phosphors in display and lighting applications due to their high photoluminescence quantum yields (PLQY). Recent efforts in the field have demonstrated that trivalent lanthanide, Ln(III), incorporated into ZnAl

Purpose To evaluate macular vasculature in diabetic retinopathy (DR) with optical coherence tomography angiography (OCTA) and to correlate vessel density (VD) with retinal sensitivity (RS) as a way to assess structural and functional findings in DR. Design Prospective observational cross-sectional study. Methods Diabetic patients with DR but no clinically significant diabetic macular edema (DME) and healthy subjects were included in this study. All of them underwent comprehensive ophthalmic examination, best corrected visual acuity (BCVA), OCTA with RS-3000 Advance AngioScan (Nidek, Gamagori, Japan) and microperimetry with MP-3 (Nidek, Gamagori, Japan). Retinal vascular density measured by OCT angiography in 9 areas was correlated with RS in the same 9 areas by Spearman correlation. Results In this study, 50 subjects were enrolled: 25 eyes of diabetic patients with DR and 25 eyes of non-diabetic subjects. Diabetic patients mean age was 51.88±13.62 years; non-diabetic subjects were 43.48±13.42 years. The BCVA was 20/25 in the diabetic group and 20/20 in the non-diabetic group. Mean RS was decreased in the DR group (27.68±2.71 dB) compared to the non-diabetic group (31.68±1.46 dB) (p

Purpose: To correlate visual field assessment with saccadic vector optokinetic perimetry (SVOP) in children with ganglion cell loss due to anterior pathway pathologies resulting in hemianopic visual field defects measured with optical coherence tomography (OCT). Methods: 5 young (aged 3-6 years) and 5 adult patients with hemianopia, 10 healthy preschoolers (mean age 4.4 years), and 10 healthy adults (mean age 25.3 years) were tested with SVOP and OCT (focusing on the ganglion cell layer, GCL+). In adults, visual field testing was also performed with static and fundus-controlled perimetry. Results: OCT allowed precise structure analysis and showed a vertical border with GCL+ loss on the hemianopic side in children and adults compared to controls. SVOP showed visual field defects on the hemianopic side in peripheral regions and inadequate results at the parafoveal positions in both groups. In contrast, static and fundus-controlled perimetry showed a clear border in foveal and parafoveal regions. Conclusions: All children underwent SVOP with minimal restrictions, allowing functional evaluation of peripheral visual field positions. Parafoveal positions showed multiple false-positive results. The function-structure relationship is measurable even in young children by using the GCL+ analysis. This combination of novel child-friendly techniques allows collecting objectively measured values and simplifies diagnosis and follow-up in treatment.

In general, proteins in the biological system interact with nanoparticles (NPs) via adsorption on the particle surface. Understanding the adsorption at the molecular level is crucial to explore NP–protein interactions. The increasing concerns about the risk to human health on NP exposure have been explored through the discovery of a handful protein biomarkers and biochemical analysis. However, detailed information on structural perturbation and associated functional changes of proteins on interaction with NPs is limited. Erythrocytes (red blood cells) are devoid of defense mechanism of protecting NP penetration through endocytosis. Therefore, it is important to investigate the interaction of erythrocyte proteins with NPs. Hemoglobin, the most abundant protein of human erythrocyte, is a tetrameric molecule consisting of α- and β-globin chains in duplicate. In the present study, we have used hemoglobin as a model system to investigate NP–protein interaction with ferric pyrophosphate NPs [NP-Fe4(P2O7)3]. We ...

Porous organic materials have garnered colossal interest with the scientific fraternity due to their excellent gas sorption performances, catalytic abilities, energy storage capacities, and other intriguing applications. This review encompasses the recent significant breakthroughs and the conventional functions and practices in the field of porous organic materials to find useful applications and imparts a comprehensive understanding of the strategic evolution of the design and synthetic approaches of porous organic materials with tunable characteristics. We present an exhaustive analysis of the design strategies with special emphasis on the topologies of crystalline and amorphous porous organic materials. In addition to elucidating the structure-function correlation and state-of-the-art applications of porous organic materials, we address the challenges and restrictions that prevent us from realizing porous organic materials with tailored structures and properties for useful applications.

Bacillus lipases are industrially attractive enzymes due to their broad substrate specificity and optimum alkaline pH. However, narrow temperature range of action and low thermostability restrain their optimal use and thus, necessitate attention. Several laboratories are engaged in protein engineering of Bacillus lipases to generate variants with improved attributes for decades using techniques such as directed evolution or rational design. This review summarizes the effect of mutations on the conformational changes through in silico modeling and their manifestation with respect to various biochemical parameters. Various studies have been put together to develop a perspective on the molecular basis of biocatalysis of lipases holding industrial importance.

To investigate regional alterations of macular microvasculature in primary open-angle glaucoma (POAG), and to determine the structure-function correlation between localized visual field defects and macular microvascular damage in matching sectors.Fifty-eight patients with POAG and 27 normal controls were recruited for this study. Optical coherence tomography angiography (OCTA) was used to measure retinal vascular microcirculation of the macula in superior, inferior, temporal, and nasal sectors. Visual field (VF) was tested using automated perimeter. Sensitivities of 16 central points of the VF were selected and divided into the 4 previously mentioned sectors. Structure-function correlation analysis was performed between localized visual field defects and the matching macular microvasculature damage. The relationship was also assessed using a previously described model.The temporal vascular density was thinner than those of the superior and inferior positions of parafovea in the control group (P 0.05). Vascular densities in all sectors were decreased in the POAG group compared with the normal control group (P 0.05). The structure-function correlation coefficients between sectors of VF sensitivity and the matched vascular densities ranged from 0.295 to 0.433 (P 0.01). The coefficient of determination between OCT derived vascular density measurements and the estimates using the previous model ranged from 0.08 to 0.19. The best fit was in the inferior sector.Compared with age-matched control subjects, vascular density of the parafoveal retina decreased in the POAG subjects. There is a moderate structure-function correlation between visual field sensitivity thresholds measured with automated perimeter and macular vascular density assessed by OCT.

The donor–acceptor benzothiazole substituted tetraphenylethylenes (BT-TPEs) 3a–3c were designed and synthesized to examine the effect of the linkage between the BT and the TPE unit on the photophysical, aggregation induced emission (AIE) and mechanochromic properties. The syntheses of BT-TPEs 3a–3c were achieved by the Pd-catalyzed Suzuki cross-coupling reaction of bromobenzothiazoles 1a–1c with 4-(1,2,2-triphenylvinyl)phenylboronic acid pinacol ester (2). The study showed that their photophysical, AIE and mechanochromic properties are dependent on the linkage between the BT and the TPE unit (ortho, meta, and para). The meta isomer 3b shows the highest grinding induced spectral shift (51 nm) whereas the ortho isomer 3a shows the lowest grinding induced spectral shift (9 nm). The single crystal X-ray structures reveal the highly twisted conformation and tight packing in BT-TPE 3a compared to 3b. The thermogravimetric analysis of BT-TPEs shows good thermal stability. The computational study reveals the donor–acceptor nature of the BT-TPEs. The structure–function correlation indicates that the mechanochromic and aggregation induced emission (AIE) properties were dependent on the linkage between BT and TPE.

To compare the diagnostic assessment of glaucoma specialists with an automated structure–function correlation report combining visual field (VF) and spectral-domain optical coherence tomography (SD-OCT) imagining in subjects with glaucoma. This prospective, cross-sectional study was conducted at Wills Eye Hospital, Philadelphia, PA, USA. Subjects with glaucoma received ophthalmic examination, VF testing, and SD-OCT imaging. An automated report was generated describing structure–function correlations between the two structural elements [retinal nerve fiber layer (RNFL) and Bruch’s membrane opening-minimum rim width (MRW)] and VF sectors. Three glaucoma specialists masked to the automated report and to each other identified clinically significant structure–function correlations between the VF and SD-OCT reports. Raw agreement and chance-corrected agreement (kappa statistics) between the automated report and the clinical assessments were compared. A total of 53 eyes from 45 subjects with glaucoma were included in this study. The overall agreement between the automated report and clinical assessment comparing MRW and VF was good at 74.8% with a kappa of 0.62 (95% CI 0.55–0.69). Agreements for the six different MRW sections were moderate to good with kappa values ranging from 0.54 to 0.69. For mean RNFL thickness and VF comparisons, agreement between the automated report and clinical assessment was 75.4% with a kappa of 0.62 (95% CI 0.54–0.70). For different RNFL sectors, kappa values ranged from 0.47 (moderate agreement) to 0.80 (good agreement). This study suggests that the automated structure–function report combining results from the SD-OCT and the HEP may assist in the evaluation and management of glaucoma.

Self-healing low molecular weight supramolecular gels (SMGs) represent an emerging class of smart materials, which can closely mimic the complex biological healing process, such as blood clotting, bone repair or wound healing. However, a lack of understanding of the structure-function correlation in the self-assembly process limits their molecular design and subsequent property tuning. The indispensability of a rheological study on supramolecular gels lies in direct transcription of the assembly property to the viscoelastic behavior of the material. This is similarly relevant to healable and non-healable systems. Thus, using rheology as a tool for elucidating structure-function relationships in self-assembled systems has huge potential. This review article will depict a general introduction of rheology in the field of soft matter including SMGs, followed by representative studies with interpretations, and discussion on future challenges. Altogether, this would be an effort, where an in-depth rheological study complemented with a real-time visualization with the help of microscopy, and introduction of other sophisticated real-time experiments, could be a step forward to capture the mystery of self-assembly process.

PURPOSE To investigate the electrophysiological features of macular telangiectasia Type 2 and their relationship to structure as determined by optical coherence tomography imaging. METHODS Forty-two eyes from 21 patients enrolled in the Macular Telangiectasia Natural History Observation Study were reviewed. All patients had full-field and pattern electroretinography (ERG; PERG) with some patients additionally having multifocal electroretinography (mfERG; N = 15) or electrooculography (N = 12). Multiple linear regression modeling assessed the relationship between the ellipsoid zone break size on optical coherence tomography and the central mfERG response. RESULTS Full-field ERG and electrooculography were normal in all eyes. Six eyes (14%) from five patients had subnormal PERG P50 amplitudes. Twenty-two of 30 eyes (73%) had reduced central or paracentral stimulus on mfERG. There was a significant correlation between ellipsoid zone break size and both the P1 amplitude (R = 0.37, P = 0.002) and P1:N1 ratio (R = 0.32, P = 0.002) of the central response on mfERG. CONCLUSION The electrophysiological findings in macular telangiectasia Type 2 are those of localized central dysfunction and are consistent with the structural data available from imaging and histologic studies. The ellipsoid zone break size correlates with mfERG reduction. The reduced mfERG P1:N1 ratio is consistent with inner retinal dysfunction.

The requirement for new antiviral therapeutics is an ever present need. Particularly lacking are broad spectrum antivirals that have low toxicity. We develop such agents based on macromolecular prodrugs whereby both the polymer chain and the drug released from the polymer upon cell entry have antiviral effects. Specifically, macromolecular prodrugs were designed herein based on poly(methacrylic acid) and ribavirin. Structure-function parameter space was analyzed via the synthesis of 10 polymer compositions varied by molar mass and drug content. Antiviral activity was tested in cell culture against both low and high pathogenic strains of influenza. Lead compounds were successfully used to counter infectivity of influenza in chicken embryos. The lead composition with the highest activity against influenza was also active against another respiratory pathogen, respiratory syncytial virus, providing opportunity to potentially treat infection by the two pathogens with one antiviral agent. In contrast, structure-function activity against the herpes simplex virus was drastically different, revealing limitations of the broad spectrum antiviral agents based on macromolecular prodrugs.

Exploring the free energy landscape of proteins and modeling the corresponding functional aspects presents a major challenge for computer simulation approaches. This challenge is due to the complexity of the landscape and the enormous computer time needed for converging simulations. The use of various simplified coarse grained (CG) models offers an effective way of sampling the landscape, but most current models are not expected to give a reliable description of protein stability and functional aspects. The main problem is associated with insufficient focus on the electrostatic features of the model. In this respect, our recent CG model offers significant advantage as it has been refined while focusing on its electrostatic free energy. Here we review the current state of our model, describing recent refinements, extensions, and validation studies while focusing on demonstrating key applications. These include studies of protein stability, extending the model to include membranes, electrolytes and electrodes, as well as studies of voltage-activated proteins, protein insertion through the translocon, the action of molecular motors, and even the coupling of the stalled ribosome and the translocon. The examples discussed here illustrate the general potential of our approach in overcoming major challenges in studies of structure function correlation in proteins and large macromolecular complexes. Proteins 2014; 82:1168–1185. © 2013 Wiley Periodicals, Inc.

Background Performance during cognitive control functional magnetic resonance imaging (fMRI) tasks are associated with frontal lobe hypoactivation in patients with bipolar disorder, even while euthymic. We examine the structural underpinnings for this functional abnormality simultaneously with brain activation data. Methods In a sample of 90 adults (45 with interepisode bipolar I disorder and 45 healthy controls), we explored abnormal functional activation patterns in euthymic patients with bipolar disorder during a Go/NoGo fMRI task and their associations with regional deficits in cortical gray matter thickness. Cross-sectional differences in fMRI activation were used to form a priori hypotheses for region of interest cortical gray matter thickness analyses. Blood oxygen level–dependent fMRI to structural magnetic resonance imaging thickness correlations were conducted across the sample and within patients and controls separately. Results During response inhibition (NoGo − Go), patients with bipolar I disorder showed significant hypoactivation and reduced thickness in the inferior frontal cortex, superior frontal gyrus, and cingulate compared to controls. Cingulate hypoactivation corresponded with reduced regional thickness. A significant activation by disease state interaction was observed with thickness in left prefrontal areas. Conclusions Reduced cingulate fMRI activation is associated with reduced cortical thickness. In the left frontal lobe, a thinner cortex was associated with increased fMRI activation in patients but showed a reverse trend in controls. These findings suggest that reduced activation in the inferior frontal cortex and cingulate during a response inhibition task may have an underlying structural etiology, which may explain task-related functional hypoactivation that persists even when patients are euthymic.

To evaluate the diagnostic power of the Posterior Pole Asymmetry Analysis (PPAA) from the SPECTRALIS OCT in glaucoma diagnosis and to define the correlation between the visual field sensitivity (VFS) and macular retinal thickness (MRT).90 consecutive open-angle glaucoma patients and 23 healthy subjects were enrolled. All subjects underwent Visual Field test (Humphrey Field Analyzer, central 24-2 SITA-Standard) and SD-OCT volume scans (SPECTRALIS, Posterior Pole Asymmetry Analysis). The areas under the Receiving Operating Characteristic curve (AROC) were calculated to assess discriminating power for glaucoma, at first considering total MRT values and hemisphere MRT value and then quadrant MRT values from 16 square cells in a 8 x 8 posterior pole retinal thickness map that were averaged for a mean retinal thickness value. Structure function correlation was performed for total values, hemisphere values and for each quadrant compared to the matching central test points of the VF.The AROCs ranged from 0.70 to 0.82 (p 0.0001), with no significant differences between each other. The highest AROC observed was in inferior nasal quadrant. The VFS showed a strong correlation only with the corresponding MRT value s for quadrant analysis: Superior Temporal (r = 0.33, p = 0.0013), Superior Nasal (r = 0.43, p 0.0001), Inferior Temporal (r = 0.57, p 0.0001) and Inferior Nasal (r = 0.55, p 0.0001).the quadrant analysis showed statistically significant structure-function correlations and may provide additional data for the diagnostic performance of SPECTRALIS OCT.

Evaluating the free-energy landscape of proteins and the corresponding functional aspects presents a major challenge for computer simulation approaches. This challenge is due to the complexity of the landscape and the enormous computer time needed for converging simulations. The use of simplified coarse-grained (CG) folding models offers an effective way of sampling the landscape but such a treatment, however, may not give the correct description of the effect of the actual protein residues. A general way around this problem that has been put forward in our early work (Fan et al., Theor Chem Acc 1999;103:77-80) uses the CG model as a reference potential for free-energy calculations of different properties of the explicit model. This method is refined and extended here, focusing on improving the electrostatic treatment and on demonstrating key applications. These applications include: evaluation of changes of folding energy upon mutations, calculations of transition-states binding free energies (which are crucial for rational enzyme design), evaluations of catalytic landscape, and evaluations of the time-dependent responses to pH changes. Furthermore, the general potential of our approach in overcoming major challenges in studies of structure function correlation in proteins is discussed.

[structure: see text] Two-photon absorption (TPA) cross-section values for a series of 22pi smaragdyrins bearing phenylacetylenylphenyl and [(phenylacetylenyl)phenylacetylenyl]phenyl meso links and their Rh(I) derivatives are reported.

This account describes work in our laboratories on the application of physical methods to the structural studies of various toxins during the past few years. A general review of background and the meaningful results obtained from these approaches are described. The results are compared with updated information on related subjects carried out at other laboratories. Examples of structural studies on some small toxins present abundantly in Formosan cobra (Naja naja atra), one of the indigenous toxic snakes in Taiwan, are given with the emphasis on the identification and characterization of complex toxic protein components based on near-infrared Fourier transform Raman Spectroscopy. We will also describe our initial efforts in solving the solution structures of several small proteins and peptides by means of two-dimensional nuclear magnetic resonance (2D-NMR) and computer-simulated modeling. The structural information obtained by these modem physical techniques provides the framework for unraveling the complex structure-activity relationships engendered by these biomolecules.

In this part of the course we will discuss the implication of the combination of the structural and functional measurement. In glaucoma structural and functional measurements provide largely independent information, and most studies indicate that their agreement is generally poor. There is s

BACKGROUND AND AIM: The aim of this work is to investigate whether optic disc hemorrhages (ODH) lead to significant loss of nerve fibers at the lesion site over time and whether such a loss is reflected by visual field defects corresponding to the affected nerve fiber bundle. METHODS: In this retrospective study of ten sequential glaucoma patients (ten eyes) with ODH, we used high-resolution OCT circular scans (Spectralis HRA + OCT, Heidelberg Engineering, Heidelberg, Germany) to determine peripapillary retinal nerve fiber layer (RNFL) thickness at the time of ODH presentation and at follow-up visit between 3 and 6 months. Corresponding perimetric data were analyzed for global (mean defect, MD) and localized progression of visual field defects. RESULTS: ODH were mostly located in the inferior quadrant as determined clinically and from fundus photographs. Iterative OCT imaging revealed a significant RNFL reduction in the affected quadrant relative to the respective quadrant in the fellow eye (RNFL change = -2.25 ± 2.69 μm vs. 0.75 ± 2.78 μm, p = 0.01) within 120 ± 43 days. However, only three cases presented with new/progressive nerve fiber bundle defects corresponding to the lesion site within the given follow-up period. CONCLUSIONS: ODH lead to a significantly higher RNFL loss at the lesion site relative to the overall structural progression in glaucoma patients. However, this focal change is not generally reflected by respective nerve fiber bundle defects in the time frame investigated.

Glaucoma is a disease affecting the optic nerve. Structural as well as functional changes occur as the disease progresses. Glaucomatous optic discs appear with certain patterns of structural damage, and the disease’s main consequence is patient’s visual field damage. Taking therapeutic decisions for glaucomatous patients requires visual field examination which until today is the cornerstone of glaucomatous patients’ management. Humphrey Field Analyzer (HFA) is the most commonly used device for visual field examination.

The glomerular structure of the primary olfactory neuropil has long been thought to play an important role in odour coding. In insects, the number of glomeruli in the antennal lobe is limited in most species to fewer than 100 compared with more than 1,000 in vertebrates, making it possible to identify individual glomeruli. A complete three-dimensional atlas of the glomeruli within the antennal lobe of the male noctuid moth Agrotis ipsilon was constructed. All 66 glomeruli were singly identifiable in both antennal lobes of the three brains investigated. Further, six antennal lobes containing intracellularly stained projection neurones were reconstructed. By using the atlas, the respective target glomerulus of each projection neurone could be identified. The importance of the glomerular atlas as a tool to study central olfactory processing and its plasticity is discussed.

Airway smooth muscle is able to adapt and maintain a nearly constant maximal force generation over a large length range. This implies that a fixed filament lattice such as that found in striated muscle may not exist in this tissue and that plastic remodeling of its contractile and cytoskeletal filaments may be involved in the process of length adaptation that optimizes contractile filament overlap. Here, we show that isometric force produced by airway smooth muscle is independent of muscle length over a twofold length change; cell cross-sectional area was inversely proportional to cell length, implying that the cell volume was conserved at different lengths; shortening velocity and myosin filament density varied similarly to length change: increased by 69.4% ± 5.7 (SE) and 76.0% ± 9.8, respectively, for a 100% increase in cell length. Muscle power output, ATPase rate, and myosin filament density also have the same dependence on muscle cell length: increased by 35.4% ± 6.7, 34.6% ± 3.4, and 35.6% ± 10.6, respectively, for a 50% increase in cell length. The data can be explained by a model in which additional contractile units containing myosin filaments are formed and placed in series with existing contractile units when the muscle is adapted at a longer length.

The ancient approach to obtain an image of the kidneys (and other internal organs) was 'section-inspection-imaging' by drawing, painting, sculpturing, and modelling. The present study follows chronologically the development and use of sectioning techniques from ancient (often forbidden) methods to modern microdissection and maceration of silicone-rubber-injected tubules. Inspection evolved from the use of the naked eye to magnifying lenses, microscopes and finally electron microscopy. Pertinent examples such as the description of the kidneys as the site of urine formation, the visualization of loop structures in the renal medulla and the imaging of tight junction strands are discussed. Inspection or visualization of renal structure and function has been revolutionized by modern noninvasive techniques, such as X-ray imaging, imaging by radioisotopes, ultrasound, computer tomography and nuclear magnetic resonance. Pertinent examples are given demonstrating the potency of the various techniques. The contribution of computerized data evaluation is discussed. The development of micropuncture and microperfusion techniques has opened the field for direct imaging not only of renal (sub)structural details but also of functional parameters such as transtubular reabsorption rates, single glomerular capillary filtration and conductance of the paracellular pathway. We focus particularly on techniques specifically designed to visualize renal hemodynamic and transport parameters.

Morphological diversity of amacrine cells (ACs) is clearly a general characteristic of vertebrate retinae. Beginning with the comparative work of Cajal (1893), much detailed information concerning the cells’ morphological features in both the plane as well as the radial extent of the retina has been obtained by Golgi impregnation (Boycott and Dowling 1969; Naka and Carraway, 1975, Perry and Walker, 1980; Ammermuller and Weiler, 1981; Famiglietti and Vaughn, 1981; Kolb et al., 1981; Vallerga and Deplano, 1984; Wagner and Wagner, 1988). The larger the number of parameters considered, the more numerous the types of AC that became morphologically differentiated. Thus, in the retina of the turtle, Kolb (1982) distinguished 22 types of AC, and in the retina of the cyprinid fish, roach, 43 types of AC were found (Wagner and Wagner, 1988). In contrast, an attempt to rationalize the morphological diversity of ACs using dendritic architecture as a qualitative parameter, as opposed to quantitative parameters, such as extent of dendritic field, size, etc. resulted in the definition of five classes of ACs in the sparid fish, bogue (Vallerga and Deplano, 1984). As regards their light-evoked responses, ACs have been divided most commonly into two broad categories: sustained and transient, in turn, the former could be depolarizing or hyperpolarizing (Kaneko and Hashimoto, 1969; Kaneko, 1973, Toyoda et al., 1973; Chan and Naka, 1975, Famiglietti et al., 1977, Murakami and Shimoda, 1977; Mitarai et al., 1978, Djamgoz et al., 1988a,).

The in vivo structure-function relationship is key to understanding brain network reorganization due to pathologies. This relationship is likely to be particularly complex in brain network diseases such as temporal lobe epilepsy, in which disturbed large-scale systems are involved in both transient electrical events and long-lasting functional and structural impairments. Herein, we estimated this relationship by analyzing the correlation between structural connectivity and functional connectivity in terms of analytical network communication parameters. As such, we targeted the gradual topological structure-function reorganization caused by the pathology not only at the whole brain scale but also both in core and peripheral regions of the brain. We acquired diffusion (dMRI) and resting-state fMRI (rsfMRI) data in seven right-lateralized TLE (rTLE) patients and fourteen healthy controls and analyzed the structure-function relationship by using analytical network communication metrics derived from the structural connectome. In rTLE patients, we found a widespread hypercorrelated functional network. Network communication analysis revealed greater unspecific branching of the shortest path (search information) in the structural connectome and a higher global correlation between the structural and functional connectivity for the patient group. We also found evidence for a preserved structural rich-club in the patient group. In sum, global augmentation of structure-function correlation might be linked to a smaller functional repertoire in rTLE patients, while sparing the central core of the brain which may represent a pathway that facilitates the spread of seizures.