Prevalence of avian influenza H5, H7, and H9 viruses in commercial layers in Karachi, Pakistan.

BACKGROUND: Avian influenza viruses (AIVs) cause significant harm to the poultry industry due to mortality as well as high morbidity along with the risk of potential zoonotic transmission to humans. AIMS: The study aimed to investigate the prevalence of influenza H5, H7, and H9 viruses and their co-infections in layers having respiratory distress such as sneezing, coughing, and tracheal rales. METHODS: Totally, 960 tracheal swabs (240 swabs in each season) were collected from 120 poultry flocks, including 10 farms per month and 8 samples per flock, located in Karachi where the outbreaks were reported. The samples were confirmed through antigen ELISA and subtyped by RT-PCR. RESULTS: Antigen ELISA revealed that the prevalence of avian influenza viruses was 26.45%; however, seasonal differences were not significant (P<0.05). RT-PCR subtyping of hemagglutinin (HA) gene revealed the higher prevalence of H9 virus (40.16%) as compared to H7 virus (5.51%) and H5 virus (4.73%). The co-infections comprised H5/H7/H9 (37.0%) and H5/H9 (12.6%). CONCLUSION: This study shows that AI is endemic in layer farms in Karachi where the H9 subtype is predominant along with co-infections of H5/H7/H9 subtypes.

Novel genotype-phenotype and MRI correlations in a large cohort of patients with SPG7 mutations.

OBJECTIVE: To clinically, genetically, and radiologically characterize a large cohort of SPG7 patients. METHODS: We used data from next-generation sequencing panels for ataxias and hereditary spastic paraplegia to identify a characteristic phenotype that helped direct genetic testing for variations in SPG7. We analyzed MRI. We reviewed all published SPG7 mutations for correlations. RESULTS: We identified 42 cases with biallelic SPG7 mutations, including 7 novel mutations, including a large multi-exon deletion, representing one of the largest cohorts so far described. We identified a characteristic phenotype comprising cerebellar ataxia with prominent cerebellar dysarthria, mild lower limb spasticity, and a waddling gait, predominantly from a cohort of idiopathic ataxia. We report a rare brain MRI finding of dentate nucleus hyperintensity on T2 sequences with SPG7 mutations. We confirm that the c.1529C>T allele is frequently present in patients with long-standing British ancestry. Based on the findings of the present study and existing literature, we confirm that patients with homozygous mutations involving the M41 peptidase domain of SPG7 have a younger age at onset compared to individuals with mutations elsewhere in the gene (14 years difference, p < 0.034), whereas c.1529C>T compound heterozygous mutations are associated with a younger age at onset compared to homozygous cases (5.4 years difference, p < 0.022). CONCLUSIONS: Mutant SPG7 is common in sporadic ataxia. In patients with British ancestry, c.1529C>T allele represents the most frequent mutation. SPG7 mutations can be clinically predicted by the characteristic hybrid spastic-ataxic phenotype described above, along with T2 hyperintensity of the dentate nucleus on MRI.

Loss of nuclear TDP-43 in amyotrophic lateral sclerosis (ALS) causes altered expression of splicing machinery and widespread dysregulation of RNA splicing in motor neurones.

AIMS: Loss of nuclear TDP-43 characterizes sporadic and most familial forms of amyotrophic lateral sclerosis (ALS). TDP-43 (encoded by TARDBP) has multiple roles in RNA processing. We aimed to determine whether (1) RNA splicing dysregulation is present in lower motor neurones in ALS and in a motor neurone-like cell model; and (2) TARDBP mutations (mtTARDBP) are associated with aberrant RNA splicing using patient-derived fibroblasts. METHODS: Affymetrix exon arrays were used to study mRNA expression and splicing in lower motor neurones obtained by laser capture microdissection of autopsy tissue from individuals with sporadic ALS and TDP-43 proteinopathy. Findings were confirmed by quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and in NSC34 motor neuronal cells following shRNA-mediated TDP-43 depletion. Exon arrays and immunohistochemistry were used to study mRNA splicing and TDP-43 expression in fibroblasts from patients with mtTARDBP-associated, sporadic and mutant SOD1-associated ALS. RESULTS: We found altered expression of spliceosome components in motor neurones and widespread aberrations of mRNA splicing that specifically affected genes involved in ribonucleotide binding. This was confirmed in TDP-43-depleted NSC34 cells. Fibroblasts with mtTARDBP showed loss of nuclear TDP-43 protein and demonstrated similar changes in splicing and gene expression, which were not present in fibroblasts from patients with sporadic or SOD1-related ALS. CONCLUSION: Loss of nuclear TDP-43 is associated with RNA processing abnormalities in ALS motor neurones, patient-derived cells with mtTARDBP, and following artificial TDP-43 depletion, suggesting that splicing dysregulation directly contributes to disease pathogenesis. Key functional pathways affected include those central to RNA metabolism.

A charge-stabilizing, multimodular, ferrocene-bis(triphenylamine)-zinc-porphyrin-fullerene polyad.

A novel multimodular donor-acceptor polyad featuring zinc porphyrin, fullerene, ferrocene, and triphenylamine entities was designed, synthesized, and studied as a charge-stabilizing, photosynthetic-antenna/reaction-center mimic. The ferrocene and fullerene entities, covalently linked to the porphyrin ring, were distantly separated to accomplish the charge-separation/hole-migration events leading to the creation of a long-lived charge-separated state. The geometry and electronic structures of the newly synthesized compound was deduced by B3LYP/3-21G(*) optimization, while the energy levels for different photochemical events was established using data from the optical absorption and emission, and electrochemical studies. Excitation of the triphenylamine entities revealed singlet-singlet energy transfer to the appended zinc porphyrin. As predicted from the energy levels, photoinduced electron transfer from both the singlet and triplet excited states of the zinc porphyrin to fullerene followed by subsequent hole migration involving ferrocene was witnessed from the transient absorption studies. The charge-separated state persisted for about 8.5 µs and was governed by the distance between the final charge-transfer product, that is, a species involving a ferrocenium cation and a fullerene radical anion, with additional influence from the charge-stabilizing triphenylamine entities located on the zinc-porphyrin macrocycle.

Tardbpl splicing rescues motor neuron and axonal development in a mutant tardbp zebrafish.

Mutations in the transactive response DNA binding protein-43 (TARDBP/TDP-43) gene, which regulates transcription and splicing, causes a familial form of amyotrophic lateral sclerosis (ALS). Here, we characterize and report the first tardbp mutation in zebrafish, which introduces a premature stop codon (Y220X), eliminating expression of the Tardbp protein. Another TARDBP ortholog, tardbpl, in zebrafish is shown to encode a Tardbp-like protein which is truncated compared with Tardbp itself and lacks part of the C-terminal glycine-rich domain (GRD). Here, we show that tardbp mutation leads to the generation of a novel tardbpl splice form (tardbpl-FL) capable of making a full-length Tardbp protein (Tardbpl-FL), which compensates for the loss of Tardbp. This finding provides a novel in vivo model to study TDP-43-mediated splicing regulation. Additionally, we show that elimination of both zebrafish TARDBP orthologs results in a severe motor phenotype with shortened motor axons, locomotion defects and death at around 10 days post fertilization. The Tardbp/Tardbpl knockout model generated in this study provides an excellent in vivo system to study the role of the functional loss of Tardbp and its involvement in ALS pathogenesis.

Influence of surgeon and hospital volume on radical prostatectomy costs.

PURPOSE: While higher radical prostatectomy hospital and surgeon volume are associated with better outcomes, the effect of provider volume on health care costs remains unclear. We performed a population based study to characterize the effect of surgeon and hospital volume on radical prostatectomy costs. MATERIALS AND METHODS: We used SEER (Surveillance, Epidemiology and End Results)-Medicare linked data to identify 11,048 men who underwent radical prostatectomy from 2003 to 2009. We categorized hospital and surgeon radical prostatectomy volume into tertiles (low, intermediate, high) and assessed costs from radical prostatectomy until 90 days postoperatively using propensity adjusted analyses. RESULTS: Higher surgeon volume at intermediate volume hospitals (surgeon volume low $9,915; intermediate $10,068; high $9,451; p = 0.021) and high volume hospitals (surgeon volume low $11,271; intermediate $10,638; high $9,529; p = 0.002) was associated with lower radical prostatectomy costs. Extrapolating nationally, selective referral to high volume radical prostatectomy surgeons at high and intermediate volume hospitals netted more than $28.7 million in cost savings. Conversely, higher hospital volume was associated with greater radical prostatectomy costs for low volume surgeons (hospital volume low $9,685; intermediate $9,915; high $11,271; p = 0.010) and intermediate volume surgeons (hospital volume low $9,605; intermediate $10,068; high $10,638; p = 0.029). High volume radical prostatectomy surgeon costs were not affected by varying hospital volume, and among low volume hospitals radical prostatectomy costs did not differ by surgeon volume. CONCLUSIONS: Selective referral to high volume radical prostatectomy surgeons operating at intermediate and high volume hospitals nets significant cost savings. However, higher radical prostatectomy hospital volume was associated with greater costs for low and intermediate volume radical prostatectomy surgeons.

Ultrafast photoinduced energy and electron transfer in multi-modular donor-acceptor conjugates.

New multi-modular donor-acceptor conjugates featuring zinc porphyrin (ZnP), catechol-chelated boron dipyrrin (BDP), triphenylamine (TPA) and fullerene (C(60)), or naphthalenediimide (NDI) have been newly designed and synthesized as photosynthetic antenna and reaction-center mimics. The X-ray structure of triphenylamine-BDP is also reported. The wide-band capturing polyad revealed ultrafast energy-transfer (k(ENT) =1.0 × 10(12) s(-1)) from the singlet excited BDP to the covalently linked ZnP owing to close proximity and favorable orientation of the entities. Introducing either fullerene or naphthalenediimide electron acceptors to the TPA-BDP-ZnP triad through metal-ligand axial coordination resulted in electron donor-acceptor polyads whose structures were revealed by spectroscopic, electrochemical and computational studies. Excitation of the electron donor, zinc porphyrin resulted in rapid electron-transfer to coordinated fullerene or naphthalenediimide yielding charge separated ion-pair species. The measured electron transfer rate constants from femtosecond transient spectral technique in non-polar toluene were in the range of 5.0 × 10(9)-3.5 × 10(10) s(-1). Stabilization of the charge-separated state in these multi-modular donor-acceptor polyads is also observed to certain level.

Nicotine, cotinine, and myosmine determination using polymer films of tailor-designed zinc porphyrins as recognition units for piezoelectric microgravimetry chemosensors.

Two electropolymerizable zinc porphyrins with receptor sites tailor-designed for selective recognition of the nicotine, cotinine, or myosmine alkaloids were synthesized. These were 5-(2-phenoxyacetamide)-10,15,20-tris(triphenylamino)porphyrinato zinc(II) 1 and 5-(2,5-phenylene-bis(oxy)diacetamide)-10,15,20-tris(triphenylamino)porphyrinato zinc(II) 2 featuring one and two pendant amide side "pincers", respectively, and three triphenylamine substituents at the meso positions of the porphyrin macrocycles capable of electrochemical polymerization. Thin polymerfilms of these porphyrins served for recognition and the piezoelectric microgravimetry (PM) for analytical signal transduction of a new chemical sensor devised for determination of these alkaloids. The films were deposited by potentiodynamic electropolymerization on the 10 MHz quartz resonators of the electrochemical quartz crystal microbalance (EQCM) without affecting the electronic structure of the porphyrin macrocycles. Under favorable flow injection analysis (FIA) conditions, the alkaloid analytes were determined at the concentration level of 0.1 mM with high sensitivity and selectivity. Affinity toward the analytes of the polymer of 2 was higher than that of 1 due to the higher binding ability offered by two pendant pincers of the former. Because of the selective receptors and PM applied under FIA conditions, the developed procedure offered an alternative to the time-consuming and relatively expensive high-performance liquid chromatography (HPLC), capillary electrophoresis (CE), and gas chromatography mass spectrometry (GC-MS) methods of detection and quantification of these alkaloids.

Ultrafast excitation transfer and charge stabilization in a newly assembled photosynthetic antenna-reaction center mimic composed of boron dipyrrin, zinc porphyrin and fullerene.

A self-assembled supramolecular triad as a model to mimic the light-induced events of the photosynthetic antenna-reaction center, that is, ultrafast excitation transfer followed by electron transfer ultimately generating a long-lived charge-separated state, has been accomplished. Boron dipyrrin (BDP), zinc porphyrin (ZnP) and fullerene (C(60)), respectively, constitute the energy donor, electron donor and electron acceptor segments of the antenna-reaction center imitation. Unlike in the previous models, the BDP entity was placed between the electron donor, ZnP and electron acceptor, C(60) entities. For the construction, benzo-18-crown-6 functionalized BDP was synthesized and subsequently reacted with 3,4-dihydroxyphenyl functionalized ZnP through the central boron atom to form the crown-BDP-ZnP dyad. Next, an alkyl ammonium functionalized fullerene was used to self-assemble the crown ether entity of the dyad via ion-dipole interactions. The newly formed supramolecular triad was fully characterized by spectroscopic, computational and electrochemical methods. Steady-state fluorescence and excitation studies revealed the occurrence of energy transfer upon selective excitation of the BDP in the dyad. Further studies involving the pump-probe technique revealed excitation transfer from the (1)BDP* to ZnP to occur in about 7 ps, much faster than that reported for other systems in this series of triads, as a consequence of shorter distance between the entities. Upon forming the supramolecular triad by self-assembling fullerene, the (1)ZnP(*) produced by direct excitation or by energy transfer mechanism resulted in an initial electron transfer to the BDP entity. The charge recombination resulted in the population of the triplet excited state of C(60), from where additional electron transfer occurred to produce C(60)(•-):crown-BDP-ZnP(•+) ion pair as the final charge-separated species. Nanosecond transient absorption studies revealed the lifetime of the charge-separated state to be ~100 µs, the longest ever reported for this type of antenna-reaction center mimics, indicating better charge stabilization as a result of the different disposition of the entities of the supramolecular triad.

Photochemical charge separation in closely positioned donor-boron dipyrrin-fullerene triads.

A series of molecular triads, composed of closely positioned boron dipyrrin-fullerene units, covalently linked to either an electron donor (donor(1)-acceptor(1)-acceptor(2)-type triads) or an energy donor (antenna-donor(1)-acceptor(1)-type triads) was synthesized and photoinduced energy/electron transfer leading to stabilization of the charge-separated state was demonstrated by using femtosecond and nanosecond transient spectroscopic techniques. The structures of the newly synthesized triads were visualized by DFT calculations, whereas the energies of the excited states were determined from spectral and electrochemical studies. In the case of the antenna-donor(1)-acceptor(1)-type triads, excitation of the antenna moiety results in efficient energy transfer to the boron dipyrrin entity. The singlet-excited boron dipyrrin thus generated, undergoes subsequent energy and electron transfer to fullerene to produce a boron dipyrrin radical cation and a fullerene radical anion as charge-separated species. Stabilization of the charge-separated state in these molecular triads was observed to some extent.

The impact of prostate size, median lobe, and prior benign prostatic hyperplasia intervention on robot-assisted laparoscopic prostatectomy: technique and outcomes.

BACKGROUND: Large prostate size, median lobes, and prior benign prostatic hyperplasia (BPH) surgery may pose technical challenges during robot-assisted laparoscopic prostatectomy (RALP). OBJECTIVE: To describe technical modifications to overcome BPH sequelae and associated outcomes. DESIGN, SETTINGS, AND PARTICIPANTS: A retrospective study of prospective data on 951 RALP procedures performed from September 2005 to November 2010 was conducted. Outcomes were analyzed by prostate weight, prior BPH surgical intervention (n=59), and median lobes >1 cm (n=42). SURGICAL PROCEDURE: RALP. MEASUREMENTS: Estimated blood loss (EBL), blood transfusions, operative time, positive surgical margin (PSM), and urinary and sexual function were measured. RESULTS AND LIMITATIONS: In unadjusted analysis, men with larger prostates and median lobes experienced higher EBL (213.5 vs 176.5 ml; p<0.001 and 236.4 vs 193.3 ml; p=0.002), and larger prostates were associated with more transfusions (4 vs 1; p=0.037). Operative times were longer for men with larger prostates (164.2 vs 149.1 min; p=0.002), median lobes (185.8 vs 155.0 min; p=0.004), and prior BPH surgical interventions (170.2 vs 155.4 min; p=0.004). Men with prior BPH interventions experienced more prostate base PSM (5.1% vs 1.2%; p=0.018) but similar overall PSM. In adjusted analyses, the presence of median lobes increased both EBL (p=0.006) and operative times (p<0.001), while prior BPH interventions also prolonged operative times (p=0.014). However, prostate size did not affect EBL, PSM, or recovery of urinary or sexual function. CONCLUSIONS: Although BPH characteristics prolonged RALP procedure times and increased EBL, prostate size did not affect PSM or urinary and sexual function.

Athermal division and selective suture ligation of the dorsal vein complex during robot-assisted laparoscopic radical prostatectomy: description of technique and outcomes.

BACKGROUND: Apical dissection and control of the dorsal vein complex (DVC) affects blood loss, apical positive margins, and urinary control during robot-assisted laparoscopic radical prostatectomy (RALP). OBJECTIVE: To describe technique and outcomes for athermal DVC division followed by selective suture ligation (DVC-SSL) compared with DVC suture ligation followed by athermal division (SL-DVC). DESIGN, SETTINGS, AND PARTICIPANTS: Retrospective study of prospectively collected data from February 2008 to July 2010 for 303 SL-DVC and 240 DVC-SSL procedures. SURGICAL PROCEDURE: RALP with comparison of DVC-SSL prior to anastomosis versus early SL-DVC prior to bladder-neck dissection. MEASUREMENTS: Blood loss, transfusions, operative time, apical and overall positive margins, urine leaks, catheterization duration, and urinary control at 5 and 12 mo evaluated using 1) the Expanded Prostate Cancer Index (EPIC) urinary function scale and 2) continence defined as zero pads per day. RESULTS AND LIMITATIONS: Men who underwent DVC-SSL versus SL-DVC were older (mean: 59.9 vs 57.8 yr, p<0.001), and relatively fewer white men underwent DVC-SSL versus SL-DVC (87.5% vs 96.7%, p<0.001). Operative times were also shorter for DVC-SSL versus SL-DVC (mean: 132 vs 147 min, p<0.001). Men undergoing DVC-SSL versus SL-DVC experienced greater blood loss (mean: 184.3 vs 175.6 ml, p=0.033), and one DVC-SSL versus zero SL-DVC were transfused (p=0.442). Overall (12.2% vs 12.0%, p=1.0) and apical (1.3% vs 2.7%, p=0.361) positive surgical margins were similar for DVC-SSL versus SL-DVC. Although 5-mo postoperative urinary function (mean: 72.9 vs 55.4, p<0.001) and continence (61.4% vs 39.6%, p<0.001) were better for DVC-SSL versus SL-DVC, 12-mo urinary outcomes were similar. In adjusted analyses, DVC-SSL versus SL-DVC was associated with shorter operative times (parameter estimate [PE]±standard error [SE]: 16.84±2.56, p<0.001), and better 5-mo urinary function (PE±SE: 19.93±3.09, p<0.001) and continence (odds ratio 3.39, 95% confidence interval 2.07-5.57, p<0.001). CONCLUSIONS: DVC-SSL versus SL-DVC improves early urinary control and shortens operative times due to fewer instrument changes with late versus early DVC control.

Charge stabilization in a closely spaced ferrocene-boron dipyrrin-fullerene triad.

New molecular triads composed of closely spaced ferrocene-boron dipyrrin-fullerene, 1 and triphenylamine-boron dipyrrin-fullerene, 2 are synthesized, and photoinduced electron transfer leading to charge stabilization is demonstrated using a femtosecond transient spectroscopic technique.

Supramolecular solar cells: surface modification of nanocrytalline TiO(2) with coordinating ligands to immobilize sensitizers and dyads via metal-ligand coordination for enhanced photocurrent generation.

An elegant method of self-assembly for modification of a TiO(2) surface using coordinating ligands followed by immobilization of variety of sensitizers and a dyad is reported. This highly versatile method, in addition to testing the photoelectrochemical behavior of different zinc tetrapyrroles, allowed the use of fairly complex structures involving more than one donor entity. Utilization of the zinc porphyrin-ferrocene dyad markedly improved the current-voltage performance of the photoelectrochemical cell through an electron transfer-hole migration mechanism. Incident photon-to-current efficiency values up to 37% were obtained for the electrode modified with the dyad, signifying the importance of photocells built on the basis of biomimetic principles for efficient harvesting of solar energy.

Gills of the snow trout, Schizothorax curvifrons heckel: a SEM study.

Using the scanning electron microscope, the gills of Schizothorax curvifrons have been studied after carrying out their primary fixation in 2.5% glutaraldehyde in 0.1 M sodiumcacodylate buffer (pH 7.3) for 24 h at 0-4 degrees C and secondary fixation in 1-4% osmiumtetraoxide in 0.1 M sodiumcacodylate buffer (pH 7.3) for 1-2 h at 0-4 degrees C. The gills are observed to comprise of gill arch, gill rakers having minute projections on their inner sides and gill filaments. The filaments originating from the gill arch are in a linear fashion and equidistant from each other, bearing secondary lamellae on both sides of the filament axis and each lamellae running parallel to the adjacent lamellae. The filament epithelium is found to be equipped with pavement cells, mucous cells and chloride cells. The pavement cells have smooth surface with sparse and irregular microridges defining their cell limits. The mucous cells are mainly found on the leading and trailing edges of the filament and the chloride cells are located close to the onset of secondary lamellae. The possible roles of these structures and cells in relation to respiration, water flow and feeding are discussed, setting thereby a platform for further studies in relation to pathology, pollution and stress conditions in aquaculture, natural and polluted environments.

Apoptosis in fresh and cryopreserved buffalo sperm.

The objectives of present study were (a) validation of annexin V/PI assay for estimation of sperm apoptosis in buffalo (Experiment 1) and (b) determining the effect of stages of cryopreservation on sperm apoptosis and its correlation with sperm motility and plasma membrane integrity (Experiment 2). In Experiment 1, different levels of apoptosis were artificially induced in buffalo semen (100x10(6)sperm/aliquot) through graded doses of camptothecin (5, 10 and 20microM/aliquot). Higher concentrations of camptothecin (10 and 20microM) successfully (P<0.05) induced apoptosis as compared to the lower (5microM) dose and/or control. In Experiment 2, semen samples (n=9, three pooled semen samples from each of the three buffalo bulls separately) were cryopreserved using vapor freezing. The mean percentage of apoptotic, necrotic and viable sperm did not differ between fresh and before freezing stages. However, freezing and thawing increased (P<0.05) the percentage of apoptotic sperm (25.4+/-0.6 vs. 36.5+/-1.9) while decreased (P<0.05) the necrotic (35.1+/-1.2 vs. 29.7+/-0.7) and viable sperm (37.2+/-1.3 vs. 32.8+/-1.9, (P<0.07). Likewise, the mean percent motility and plasma membrane integrity decreased (P<0.05) (64+/-2.1 vs. 49.4+/-1.3) and (79.6+/-0.5 vs. 38.7+/-0.3) respectively, at post thaw compared to other stages. Coefficient of correlation, combined at all stages for each variable revealed that sperm apoptosis was inversely correlated with sperm motility and plasma membrane integrity. It is concluded that (a) the annexin V/PI assay can be used as a tool to determine the buffalo semen apoptosis and (b) freezing and thawing induces apoptosis in buffalo sperm.

Multi-triphenylamine-substituted porphyrin-fullerene conjugates as charge stabilizing "antenna-reaction center" mimics.

A new concept of charge stabilization via delocalization of the pi-cation radical species over the donor macrocycle substituents in a relatively simple donor-acceptor bearing multimodular conjugates is reported. The newly synthesized multimodular systems were composed of three covalently linked triphenylamine entities at the meso position of the porphyrin ring and one fulleropyrrolidine at the fourth meso position. The triphenylamine entities were expected to act as energy transferring antenna units and to enhance the electron donating ability of both free-base and zinc(II) porphyrin derivatives of these pentads. Appreciable electronic interactions between the meso-substituted triphenylamine entities and the porphyrin pi-system were observed, and as a consequence, these moieties acted together as an electron-donor while the fullerene moiety acted as an electron-acceptor in the multimodular conjugates. In agreement with the spectral and electrochemical results, the computational studies performed by the DFT B3LYP/3-21G(*) method revealed delocalization of the frontier highest occupied molecular orbital (HOMO) over the triphenylamine entities in addition to the porphyrin macrocycle. Free-energy calculations suggested that the light-induced processes from the singlet excited state of porphyrins are exothermic in the investigated multimodular conjugates. The occurrence of photoinduced charge-separation and charge-recombination processes was confirmed by the combination of time-resolved fluorescence and nanosecond transient absorption spectral measurements. Charge-separated states, on the order of a few microseconds, were observed as a result of the delocalization of the pi-cation radical species over the porphyrin macrocycle and the meso-substituted triphenylamine entities. The present study successfully demonstrates a novel approach of charge-stabilization in donor-acceptor multimodular conjugates.

Management of difficult intubation in a patient with ankylosing spondylitis--a case report.

We describe a case of difficult intubation in a patient suffering from ankylosing spondylitis undergoing total hip replacement surgery. The anesthetic management of 42 year old patient with difficult airway is discussed. Failure of epidural anesthesia procedure necessitated general anesthesia. The problems of performing awake fibreoptic intubation and other alternative techniques to secure the airway are described. Cervical spine involvement in ankylosing spondylitis is of great concern for the anesthetist. Longstanding progressive course of this disease leads to fibrosis, ossification and ankylosis of entire spine and sacroiliac joints. Cervical spine mobility is decreased and in severe cases total fixity occurs in a flexed position. Patient may also have atlanto-occipital and temporo-mandibular joint involvement as well. Cricoarytenoid cartilages involvement may result in upper airway compromise. Furthermore cervical spine vertebrae are prone to fractures, especially on hyperextension and may lead to spinal cord transection and quadriplegia. In this case report we describe the airway management of such patient with fixed rigidity of cervical spine and thoracolumbar kyphosis.