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The Synthetic Biology Open Language (SBOL) is a community-developed data standard that allows knowledge about biological designs to be captured using a machine-tractable, ontology-backed representation that is built using Semantic Web technologies. While early versions of SBOL focused only on the description of DNA-based components and their sub-components, SBOL can now be used to represent knowledge across multiple scales and throughout the entire synthetic biology workflow, from the specification of a single molecule or DNA fragment through to multicellular systems containing multiple interacting genetic circuits. The third major iteration of the SBOL standard, SBOL3, is an effort to streamline and simplify the underlying data model with a focus on real-world applications, based on experience from the deployment of SBOL in a variety of scientific and industrial settings. Here, we introduce the SBOL3 specification both in comparison to previous versions of SBOL and through practical examples of its use.

The synthetic biology design process has traditionally been heavily dependent upon manual searching, acquisition and integration of existing biological data. A large amount of such data is already available from Internet-based resources, but data exchange between these resources is often undertaken manually. Automating the communication between different resources can be done by the generation of computational workflows to achieve complex tasks that cannot be carried out easily or efficiently by a single resource. Computational workflows involve the passage of data from one resource, or process, to another in a distributed computing environment. In a typical bioinformatics workflow, the predefined order in which processes are invoked in a synchronous fashion and are described in a workflow definition document. However, in synthetic biology the diversity of resources and manufacturing tasks required favour a more flexible model for process execution. Here, the authors present the Protocol for Linking External Nodes (POLEN), a Cloud-based system that facilitates synthetic biology design workflows that operate asynchronously. Messages are used to notify POLEN resources of events in real time, and to log historical events such as the availability of new data, enabling networks of cooperation. POLEN can be used to coordinate the integration of different synthetic biology resources, to ensure consistency of information across distributed repositories through added support for data standards, and ultimately to facilitate the synthetic biology life cycle for designing and implementing biological systems.

Scientific Background: Leptomeningeal carcinomatosis (LMC) is one of the complications of systemic cancers with the most poor prognosis. Tumor cells in LMC disturb CSF circulation either by spreading into su-baracnoid space or directly infiltrating meninx and occasionaly causes intracranial hypertension (IH). Hydrocephalus can be established by ne-uroimaging methods in the most of patients with IH due to LMC. Me-ningeal contrast enhancements are also present in some patients. CSF cytology must be examined in patients with IH because of not to missing diagnosis of LMC. Material and method: Three patients presented with IH without findings of hydrocephalus in neuroimaging were diagnosed as LMC by CSF cytologic examination. IH and LMC were initial manifestations of breast carcinoma in the first patient. Our second patient was admitted with epileptic seizures and IH two years after the primary diagnosis of breast cancer. However, the fourth cytologic examination of CSF showed LMC by showing malignant cells. The last patient presented with IH was di- agnosed as gastric carcinoma one and a half month ago and LMC was diagnosed by both CSF cytology and cranial magnetic resonance imaging studies. Conclusions: LMC should be suspected in IH patients even in the absence of hydrocephaly and/or meningeal contrast enhancement in ne-uroimaging and CSF cytology must examined even if there is no history of cancer

In the current study, we synthesized a new SiPc derivative conjugated with arginine at the axial positions, for a novel phthalocyanine-based photosensitizer for photodynamic therapy (PDT) applications in cancer cells. Axially-di-arginine substituted new silicon(IV) phthalocyanine photosensitizer (PS-5a) has been thoroughly researched for its anti-cancer properties. Various spectroscopic techniques were used to characterize this conjugate, including 1 H NMR, 13 C NMR, FT-IR, UV-vis, and MS spectral data. The in vitro PDT activities of the conjugate on cancer cells were tested through its cytotoxic, clonogenic, apoptotic effects on, and its capacity to induce DNA damage, and the disruption of mitochondrial membrane potential in cancer cell lines (liver; HuH-7, cervix; HeLa and breast; MCF7). Cancer cells exposed to the light illumination following uptake of the PS-5a as a photosensitizer revealed DNA breakage and collapsed mitochondrial membrane potential. The results of the present investigation demonstrate that PS-5a has a significant photo-cytotoxic effect on cancer cells. So, axially-di-arginine substituted silicon(IV) phthalocyanine could be an effective PDT agent for PDT treatment., Competing Interests: Declaration of Competing Interest There are no conflicts to declare., (Copyright © 2023 Elsevier B.V. All rights reserved.)

In this study, compounds 1 and 2, and their silicon(iv) phthalocyanine (SiPc) derivatives 3 and 4, which bear these ligands as substituents on the axial positions were synthesized. These SiPcs (3 and 4) were also converted to their water soluble derivatives (3a and 4a). All these novel compounds were fully characterized by a combination of spectroscopic data such as FT-IR, 1 H-NMR, 13 C-NMR and UV-vis as well as mass spectroscopy. The photophysicochemical properties (fluorescence quantum yields and lifetimes, singlet oxygen, and photodegradation quantum yields) were investigated in DMSO for all the studied SiPcs (3 and 4) and in both DMSO and aqueous solutions for the water soluble SiPcs (3a and 4a). Effects of quaternization of these phthalocyanines on photophysicochemical properties were also determined. The photodynamic therapy activities of the water soluble SiPcs (3a and 4a) were tested against to the HeLa cancer cell lines and these phthalocyanines exhibited cytotoxicity against these cell lines.

Key Points: The embryonic PHOX2B-progenitor domain generates neuronal and glial cells which together are involved in chemosensory control of breathing and sleep homeostasis. Ablating PHOX2B-derived astrocytes significantly contributes to secondary hypoxic respiratory depression as well as abnormalities in sleep homeostasis. PHOX2B-derived astrocyte ablation results in axonal pathologies in the retrotrapezoid nucleus., Abstract: We identify in mice a population of ∼800 retrotrapezoid nucleus (RTN) astrocytes derived from PHOX2B-positive, OLIG3-negative progenitor cells, that interact with PHOX2B-expressing RTN chemosensory neurons. PHOX2B-derived astrocyte ablation during early life results in adult-onset O 2 chemoreflex deficiency. These animals also display changes in sleep homeostasis, including fragmented sleep and disturbances in delta power after sleep deprivation, all without observable changes in anxiety or social behaviours. Ultrastructural evaluation of the RTN demonstrates that PHOX2B-derived astrocyte ablation results in features characteristic of degenerative neuro-axonal dystrophy, including abnormally dilated axon terminals and increased amounts of synapses containing autophagic vacuoles/phagosomes. We conclude that PHOX2B-derived astrocytes are necessary for maintaining a functional O 2 chemosensory reflex in the adult, modulate sleep homeostasis, and are key regulators of synaptic integrity in the RTN region, which is necessary for the chemosensory control of breathing. These data also highlight how defects in embryonic development may manifest as neurodegenerative pathology in an adult., (© 2019 The Authors. The Journal of Physiology © 2019 The Physiological Society.)

Trametes versicolor can degrade bark as a source for carbon necessity. Therefore, it secretes lignin peroxidase, mangan peroxidase, and laccase. The laccase enzyme was produced in high yield at pH of 5 and glucose concentration of 10 g L -1 . In optimized medium, the enzyme activity was between 200 and 250 U L -1 when an inducer was absent. It was seen that the activity reached 400 U L -1 when phenol was used as an inducer. The molecular weight of purified laccase was found to be 80 kDa with SDS-PAGE, and kinetic constant K m and V max values for 2,2'-azino-bis(3-ethylbenzthiazoline)-6-sulfonate were determined to be 3.66 × 10 -4 μM and 1652 U L -1 , respectively. Because of these properties, these enzymes are widely used, free or immobilized, in industrial areas. Laccase enzyme decolorization of six different dyes was carried out. A decolorization capacity of 50-99% was achieved by cultivation for 20 days using a beginning dye concentration of 20 ppm. The removal of color with an active enzyme was obtained around 90%. Also, the laccase enzyme was conjugated, amine-functionalized, low-symmetry phthalocyanine. This conjugate was examined by both photodynamic therapy and chemosensor application. This conjugate fluorescence had a quantum yield of 0.32 (lifetime 3.59 ns) and efficiently generated singlet oxygen (quantum yield 0.4). The conjugate successfully displayed photodamage in HeLa and HuH-7 cells in the photodynamic therapy application. These results indicate that the conjugate represents an interesting agent with potential applications in photodynamic therapy. In addition, the chemosensor behavior of this compound to different metal ions has been studied, and this conjugate is displayed as a fluorescence chemosensor for the determination of Fe 3+ ions.

In this study, morpholinoethoxy-substituted metal-free (3), zinc(II) (4) and indium(III) (5) phthalocyanines were synthesized. These phthalocyanines were converted to their water-soluble quaternized derivatives (3Q-5Q) using excess methyl iodide as a quaternization agent. All these phthalocyanines (Pcs) were characterized by elemental analysis and different spectroscopic methods such as FT-IR, 1 H NMR, UV-Vis and mass spectrometry. The photophysical and photochemical properties such as fluorescence and generation of singlet oxygen were investigated for determination of these phthalocyanines as photosensitizers in photodynamic therapy (PDT) applications. The binding properties of quaternized phthalocyanines (3Q-5Q) to calf thymus DNA (CT-DNA) were investigated by UV-Vis and fluorescence spectrophotometric methods. The quenching effect of all quaternized phthalocyanines on the fluorescence intensity of SYBR Green-DNA complex was determined. The mixtures of 3Q, 4Q or 5Q and DNA solutions were used to determine the change in T m of double helix DNA with thermal denaturation profile. In addition, thermodynamic parameters considering their aggregation in buffer solution, which shows the spontaneity of the reactions between DNA and quaternized Pcs were investigated. On the other hand, in vitro phototoxicity and cytotoxicity behavior of the quaternized water-soluble phthalocyanine photosensitizers (3Q-5Q) were tested against the cervical cancer cell line named HeLa for evaluation of their suitability for treatment of cancer by PDT method. Peripherally tetra-substituted neutral and quaternized metal-free and metallophthalocyanines (MPcs) (Zn, In) bearing morpholinoethoxy groups were prepared. The binding of quaternized compounds (3Q-5Q) to CT-DNA were examined using UV-Vis, fluorescence spectra, thermal denaturation profiles and K SV values. Besides, thermodynamic studies indicated that binding of 3Q-5Q to DNA was spontaneous. On the other hand, in vitro phototoxicity and cytotoxicity behavior of the quaternized water-soluble phthalocyanine photosensitizers (3Q-5Q) were tested against the cervical cancer cell line named HeLa for evaluation of their suitability for treatment of cancer by PDT method.

Axially di-(alpha,alpha-diphenyl-4-pyridylmethoxy) silicon(IV) phthalocyanine (3) and its quaternized derivative (3Q) were synthesized and tested as photosensitizers against tumor and bacterial cells. These new phthalocyanines were characterized by elemental analysis, and different spectroscopic methods such as FT-IR, UV-Vis, MALDI-TOF and 1 H NMR. The photophysical properties such as absorption and fluorescence, and the photochemical properties such as singlet oxygen generation of both phthalocyanines were investigated in solutions. The obtained values were compared to the values obtained with unsubstituted silicon(IV) phthalocyanine dichloride (SiPcCl 2 ). The addition of two di-(alpha,alpha-diphenyl-4-pyridylmethanol) groups as axial ligands showed an improvement of the photophysical and photochemical properties and an increasement of the singlet oxygen quantum yield (Φ Δ ) from 0.15 to 0.33 was determined. The photodynamic efficacy of synthesized photosensitizers (3 and 3Q) were evaluated with promising photocytotoxicity (17% cell survival for 3 and 28% for 3Q) against the cervical cancer cell line (HeLa). The photodynamic inactivation of pathogenic bacterial strains Streptococcus mutans, Staphylococcus aureus, and Pseudomonas aeruginosa suggested a high susceptibility with quaternized derivative (3Q). The both Gram-positive bacterial strains were fully photoinactivated with 11μM 3Q and mild light dose 50J.cm -2 . In case of P. aeruginosa the effect was negligible for concentrations up to 22μM 3Q and light dose 100J.cm -2 . The results suggested that the novel axially substituted silicon(IV) phthalocyanines have promising characteristic as photosensitizer towards tumor cells. The quaternized derivative 3Q has high potential for photoinactivation of pathogenic bacterial species., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Study Design: Atlas fractures are evaluated according to the fracture type and ligamentous injury. External immobilization may result in fracture nonunion., Objective: The ideal treatment method for non-stabilized atlas fractures is limited fixation without restricting the range of motion of the atlantoaxial and atlantooccipital joints., Summary of Background Data: Such a result can be established by using either anterior fixation or posterior lateral mass fixation. However, none of these techniques can fully address anterior 1/2 atlas fractures such as in this case., Materials and Methods: A transoral technique in which bilateral screws were placed intralaminarly and connected with wire was used to reduce and stabilize an anterior 1/2 fracture of C1., Result: Radiological studies after the surgery showed good cervical alignment, no screw or wire failure and good reduction with fusion of anterior arcus of C1., Conclusions: Internal immobilization by this screw and wire osteosynthesis technique protects the mobility of the atlanto-occipital and atlantoaxial joints. The main advantage is that neither the twisted wires inserted under the anterior lamina, nor the laterally placed screw heads interfere with midline wound closure; unlike the plate/cage and rod systems used together with anterior screws. A computer navigation system with intraoperative 3D imaging facilities will be of benefit for safe placement of the screw, however we preferred a free-hand technique, as the starting point was at the fracture line along the trajectory of the routinely accessible anterior lamina., Competing Interests: There are no conflicts of interest.

Phthalocyanine-BODIPY dye (BODIPY = boron dipyrromethene) was synthesized, fully characterized, and used for molecular recognition of CYFRA 21-1, a lung cancer biomarker, from whole blood samples. Thin films of three magnesium oxides ((MgO) n , where n = 8, 9, or 10)) were deposited on a paper substrate, and they were immersed in a solution of phthalocyanine-BODIPY dye (1.17 × 10 -3  mol/L) for the design of stochastic sensors. Limits of determination of picograms per milliliter magnitude order were recorded for the proposed stochastic sensors. CYFRA 21-1 was reliably identified and determined with recoveries higher than 95% and RSD lower than 1% in whole blood samples.

Two novel silicon(IV) phthalocyanines bearing 1,3-bis[3(dimethylamino)phenoxy]propan-2-ol or 1,3-bis[3(diethylamino)phenoxy]propan-2-ol groups at their axial positions were synthesized. These phthalocyanines were converted into their water soluble derivatives by the quaternization reaction with methyl iodide. The quaternized phthalocyanines show excellent solubility aqueous solutions without any aggregation which makes them potential photosensitizers for use in photodynamic therapy (PDT). For this reason, the photophysical and photochemical properties such as fluorescence quantum yields, lifetimes, singlet oxygen generation and photodegradation of both non-ionic (3 and 5) and quaternized cationic silicon(IV) phthalocyanines were investigated. Furthermore, the cytotoxicity of PDT was determined by colorimetric proliferation assay against to hepatocellular carcinoma (HuH-7) cancer cells. In this study, the cells were incubated with a novel water soluble silicon(IV) phthalocyanine derivatives and thereafter the cells were illuminated using broad-band incoherent light source.

A series of phthalocyanine-peptide-quencher conjugates (6-9) were synthesized as photosensitizers for photodynamic therapy in cancer treatment. The photophysical, photochemical and photobiological properties of these activatable molecular beacons were also investigated in this study. For this purpose, the fluorescence, singlet oxygen and photodegradation quantum yields and fluorescence lifetime values of the compounds were determined in DMSO solutions. The phototoxicity and cytotoxicity of the systems were studied against the cervical cancer cell line named HeLa for an evaluation of their suitability for photodynamic therapy. The results showed that a maximum of 80% of HeLa cells were killed following light irradiation with photodynamic efficiency. All of the results showed that the novel activatable molecular beacons could be suitable candidates for cancer treatment via PDT technique.

Zinc(II) phthalocyanine containing [2-(tert-butoxycarbonyl)amino]ethoxy and iodine groups (A and B), as well as their deprotected mono-amino and tri-iodine zinc(II) phthalocyanine (2) were obtained. This structure surrounds by substituents with functional groups. From this perspective it can be used a starting material for many reactions and applications, such as sonogashira coupling, carbodiimide coupling. An example of a first diversification reaction of this compound was obtained with conjugation of a biotin. Asymmetrically biotin conjugated and heavy atom bearing zinc(II) phthalocyanine (3) were synthesized characterized for the first time and photophysical, photochemical and photobiological properties of these phthalocyanines were compared in this study., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Study Design: Fractures of the atlas are classified based on the fracture location and associated ligamentous injury. Among patients with atlas fractures treated using external immobilization, nonunion of the fracture could be seen., Objective: Ideally, treatment strategy for an unstable atlas fracture would involve limited fixation to maintain the fracture fragments in a reduced position without restricting the range of motion (ROM) of the atlantoaxial and atlantooccipital joints., Summary of Background Data: Such a result can be established using either transoral limited internal fixation or limited posterior lateral mass fixation. However, due to high infection risk and technical difficulty, posterior approaches are preferred but none of these techniques can fully address anterior 1/4 atlas fractures such as in this case., Materials and Methods: A novel open and direct technique in which a unilateral lag screw was placed to reduce and stabilize a progressively widening isolated right-sided anterior 1/4 single fracture of C1 that was initially treated with a rigid cervical collar is described., Results: Radiological studies made after the surgery showed no implant failure, good cervical alignment, and good reduction with fusion of C1., Conclusions: It is suggested that isolated C1 fractures can be surgically reduced and immobilized using a lateral compression screw to allow union and maintain both C1-0 and C1-2 motions, and in our knowledge this is the first description of the use of a lag screw to achieve reduction of distracted anterior 1/4 fracture fragments of the C1 from a posterior approach. This technique has the potential to become a valuable adjunct to the surgeon's armamentarium, in our opinion, only for fractures with distracted or comminuted fragments whose alignment would not be expected to significantly change with classical lateral mass screw reduction.

Peripherally and non-peripherally tetra-substituted zinc(ii) phthalocyanines bearing 2-(2-{2-[3-(dimethylamino)phenoxy]ethoxy}ethoxy)ethoxy and 2-(2-{2-[3-(diethylamino)phenoxy]ethoxy}ethoxy)ethoxy groups (, , and ) were synthesized by cyclotetramerization of the corresponding phthalonitriles (, , and ). Their quaternized ionic derivatives (, , and ) were also synthesized by the reaction of them with methyl iodide. The novel compounds were characterized by using standard spectroscopic techniques such as FT-IR, (1)H NMR, (13)C NMR, UV-vis, mass and elemental analyses. The obtained quaternized phthalocyanines (, , and ) showed amphiphilic behaviour with excellent solubility in both organic and aqueous solutions, which makes them potential photosensitizers for use in photodynamic therapy (PDT) of cancer. The photophysical (fluorescence quantum yields and lifetimes) and photochemical (singlet oxygen and photodegradation quantum yields) properties of these novel phthalocyanines were studied in DMSO for both non-ionic and ionic quaternized derivatives. However, these properties were examined in both DMSO and phosphate buffer solution (PBS) for quaternized ionic phthalocyanines. The effects of the positions of substituents (peripheral or non-peripheral) and the quaternization of the nitrogen atoms on the substituents about their photophysical and photochemical properties were also compared in this study. The bovine serum albumin (BSA) binding behaviours of the studied quaternized ionic zinc(ii) phthalocyanines were also described in PBS solutions. The quaternized phthalocyanines (, , and ) successfully displayed light-dependent photodamage in HeLa and HuH-7 cancer cells in photodynamic therapy treatment. The photosensitivity and the intensity of damage were found directly related to the concentration of the photosensitizers.

We measured the temporal profile and cellular identification of apoptosis in rat brain after cortical contusion injury. Double staining immunohistochemistry was also used to investigate the relationship between apoptotic cell death and selective protein expression associated with DNA damage and repair (p53, Bax, MDM2, WAF1, Gadd45, PCNA) and cell cycle protein, Cyclin D1, in male Wistar rats 48 h after injury. Cortical contusion was induced in male Wistar rats with a pneumatic impactor device. The animals were sacrificed at different times after trauma (1, 2, and 14 h and 1, 2, 4, 7 and 14 days; n=4 per time point). Sham-operated rats (n=4) and normal rats not subjected to any surgical procedure (n=4) were used as controls for temporal profile determination. Additional 11 rats were used for study of protein expression. Coronal brain sections were analyzed using an in situ terminal deoxynucleotdyl transferase-mediated biotinylated deoxyuridine triphosphate nick end labeling (TUNEL), hematoxylin, and immunohistochemical double staining methods. Apoptotic cells were observed as early as 2 h after the impact. Apoptotic cell death peaked at 2 days, gradually tapering off afterward, although scattered apoptotic cells were detected at 2 weeks after the impact. The number of apoptotic cells at 2 days far exceeded their number at other times (p=0.009). Apoptotic cells were observed primarily in the cortex adjacent to the site of injury. In addition, apoptotic cells in conjunction with few injured cells were present in the ipsilateral hippocampus and localized to the granule layer of dentate gyrus. Our data indicate that DNA fragmentation is present in nearly all neurons subacutely after cortical contusion and persists for at least 2 weeks thereafter. Apoptosis is also present in neurons localized to the hilus of the dentate gyrus at a site remote from the area of injury suggesting a selective role for apoptosis in promoting secondary brain damage and dysfunction after traumatic brain injury. Using double staining, we were able to show that a great majority of apoptotic cells (>95%) were neurons and the rest were astrocytes and endothelial cells. Proteins associated with DNA damage and repair (p53, Bax, MDM2, WAF1, Gadd 45, PCNA) were expressed in the cytoplasm of normal cells of naive and sham rats. These proteins were translocated to the nuclei of apoptotic and injured cells at 48 h after cortical contusion. Cyclin D1 was not present in apoptotic cells. The differential expression of proteins associated with DNA damage, repair and the cell cycle protein Cyclin D1 in the contused brain suggest a potential role for these proteins in cell survival and apoptosis after cortical contusion., (Copyright 1999 Elsevier Science B.V.)

Cisternal blood injection in the rat and squirrel monkey produces a biphasic cerebral vasospasm, a decrease in cerebral blood flow (CBF) and an increase in glucose uptake (CMRglu) due to an anaerobic glucolysis actually representing a decrease in metabolism. Lesioning of the A2-nucleus, its ascending cathecolamine pathways or their projection site, the median eminence in the hypothalamus, prevents the occurrence of spasm. A unilateral postganglionic trigeminal lesion causes an ipsilateral constriction of the cerebral arteries while a preganglionic lesion does not affect the baseline arterial diameter. Both kinds of trigeminal lesions induce a global increase in glucose uptake of about 50% without influencing CBF. Following subarachnoid hemorrhage (SAH) the decrease in CBF in both groups of lesioned animals is similar to that seen in controls. After SAH there is no further change in CMRglu in the animals with a preganglionic lesion, while in the postganglionically lesioned animals there is an additional increase in CMRglu of about 50% as compared to controls or animals with a preganglionic lesion. Treatment with the peptidergic substance P (SP) antagonist, spantide, or gammaglobulin against SP prevents or significantly reduces the degree of spasm and the changes in flow and metabolism normally seen post-SAH. The non-peptidergic neurokinins NK1 and NK3 antagonists do not influence flow and metabolism in SAH animals. The NK2 seems to change both flow and metabolism post-SAH in rats.

We examined the effects of subarachnoid hemorrhage (SAH) and treatment with deferoxamine (DFO) or sympathectomy on vascular smooth muscle function, as well as the underlying mechanisms involved, by recording the responses to nor-adrenaline and serotonin in isolated carotid arteries in vitro. All studies were performed before and 7 days after SAH. An experimental subarachnoid hemorrhage model was created in rabbits by injecting autologous arterial blood into the subarachnoid space of the rabbits via cisterna magna punction. During the chronic stage of vasospasm following SAH deferoxamine (DFO) was given to the animals and cervical and periarterial sympathectomy was performed in the other groups of animals. In isolated carotid arteries noradrenaline (10(-8) to 10(-4) mol/l) and serotonin (10(-8) to 10(-4) mol/l) produced concentration-dependent contractions. These contractile responses were significantly enhanced in animals 7 days after SAH compared to controls and did not return to control values in carotid arteries obtained from animals treated with DFO or sympathectomy for 7 days after SAH. These results show that SAH causes supersensitivity in the carotid as well as cerebral arteries during the first week after SAH and could contribute to the development of cerebral vasospasm. Both treatment with DFO and sympathectomy after SAH did not reduce the contractile responses to noradrenaline and serotonin in the carotid arteries. In conclusion, treatment with DFO or sympathectomy during the chronic stage of vasospasm after SAH did not affect the vascular responses of the extradural part of the carotid artery to vasoactive substances.

The influence of cervical and periarterial sympathectomy on endothelium-dependent and endothelium-independent relaxations of the mature rabbit carotid artery was studied in vitro. The responses to adenosine, vasoactive intestinal polypeptide and substance P in sympathectomized and control rabbit carotid artery rings were recorded and analyzed. The effects of endothelium removal were also investigated. The maximal relaxation achieved by substance P, which produces endothelium-dependent relaxation, was significantly inhibited in 3 weeks in postsympathectomy arterial preparations as compared to controls. Adenosine and vasoactive intestinal polypeptide, which produce endothelium-independent relaxation, elicited similar relaxation in all tissues. These results demonstrated that the response to substance P was impaired by cervical and periarterial sympathectomy. The decreased maximum response to substance P may be the result of a decreased NK-1 receptor subtype density or excitation/response coupling, or it may be due to an impaired production and/or liberation of endothelium-derived relaxing factor (EDRF).

1. In the present study we have studied the effects of deferoxamine treatment on lipid peroxidation and Na-K ATPase activity after experimental induction of subarachnoid haemorrhage (SAH) in guinea pigs. 2. We assessed the extent of lipid peroxidation by measuring the level of malondialdehyde and Na-K ATPase activity in 3 different groups (sham-operated, SAH, SAH + deferoxamine). 3. There was no significant difference in lipid peroxide content between sham-operated and haemorrhagic animals, but Na-K ATPase activity decreased after SAH. 4. Deferoxamine treatment reduced the malondialdehyde content and induced the recovery of Na-K ATPase activity, exerting a brain protective role against the detrimental effects of the haemorrhage.

To assess the effects of microvascular temporary clip application on vessel relaxing capability and endothelial substance release, the carotid rings of rats clipped for various durations were studied via bioassay. Noradrenaline and phenylephrine produced an immediate contraction and subsequent relaxation that failed to be suppressed by lysine acetylsalicylate or nicotine in the controls and in the arteries clipped for 0.5, 1, and 5 minutes; however, this relaxation was greatly reduced when the duration was 10 minutes. The results suggest the possible role of inadequate endothelium-derived relaxing factor release following prolonged application of the clips.