Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Ink”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,009 records · Page 56Linked to original sources
PubMed1982

The use of phagocytic peritoneal exudate cells as targets for the estimation of cytotoxic T cell activity.

A new method for measuring cytotoxic T lymphocyte (CTL) activity has been developed with peritoneal exudate cells (PECs) as target. A monolayer of target PECs was labelled with Indian ink and exposed to CTL. After incubation, detached or damaged PECs were rinsed out of the target monolayer, and the remaining phagocytes were fragmented and dissolved by the addition of 2 N NaOH. The number of undamaged target cells was estimated by colorimetric reading of the amount of Indian ink in the phagocytes surviving CTL attack. In studies with several strains of mice, only PECs from the same strain as the stimulator cell donors used for CTL induction were damaged by CTL effectors. When CTLs generated against TNP-modified syngeneic stimulators were used as effectors TNP syngeneic PECs, but neither unmodified syngeneic PECs nor allogeneic TNP-PECs, were damaged. These results demonstrate the antigen specificity of immunolysis of PECs. Macrophage target cells were stable and showed no tendency to spontaneous cell damage during 24 h incubation without effector cells.

Animals↗
PubMed1994

Pristane retards clearance of particulate materials from the peritoneal cavity of laboratory mice.

The effect of intraperitoneal pristane on the movement of India ink particles and water-based radio-opaque dye injected into the peritoneal cavity of mice was examined. There was a marked difference between pristane-treated mice and unmanipulated controls in terms of particle retention; unmanipulated mice cleared India ink particles via lymphatic drainage within 24 h following injection, whereas pristane-treated mice retained particles for as long as 22 days post-injection. In contrast, all mice displayed similar kinetics of removal of radio-opaque dye. We conclude that the movement of particulate matter from the peritoneal cavity is retarded in pristane-treated mice whereas removal of water-based materials is unaffected. The implications for generation of ascites using hybridoma cells in pristane-primed mice is discussed.

Animals↗
PubMed1992

Peri-insular presence of collagenase during islet isolation procedures.

Reportedly, higher islet yields are obtained by ductal collagenase administration and subsequent digestion of the pancreas than by the chopped tissue collagenase digestion technique. However, the exact mechanism of islet isolation is not known. This study aims to understand the underlying mechanism of a favorable effect of ductal collagenase administration. To this end, we investigated if the higher yields can be explained by a different distribution of the collagenase enzymes in the pancreatic tissue after ductal application as compared to during chopped tissue digestion. India ink was used to mimic and visualize the distribution of collagenase in histological sections of pancreases of several species. Ink particles were seen around and even within the islets both after ductal application and during chopped tissue collagenase digestion. Thus, collagenase enzymes are not restricted to the exocrine tissue compartment with either technique. In view of this observation, we compared the efficacy of both techniques in islet isolation procedures in paired experiments in rats. Both techniques gave similar islet yields to those reportedly obtained with the ductal collagenase method. However, with either technique, the islet yield was only approximately 50% of the endocrine volume of the pancreas, indicating that a substantial loss of islet tissue had occurred. We conclude that, irrespective of the route of collagenase administration, collagenase enzymes are present in the peri-insular space during islet isolation procedures. This is pertinent in view of the finding that both methods have similar islet yields in rats and that collagenase digestion, as such, is associated with loss of islet tissue.

Animals↗
PubMed1988

Measurement of cerebral capillary perfusion with a fluorescent label.

The aim of this study was to evaluate methods of labeling the perfused cerebral capillary bed using fluorescein isothiocyanate (FITC)-dextran or FITC-globulin. An alkaline phosphatase stain was used to identify the total capillary bed. All experiments were conducted on anesthetized rats. FITC labels were injected and the rats were sacrificed either 20 sec or 6 min after injection. Heads were frozen in liquid N2 or dry ice-cooled methanol. An additional group was perfused with India ink. Comparisons were made between FITC labels and methods of slide analysis. No significant differences in cerebral capillary number per square millimeter or volume per cubic millimeter were found in animals in which the heads were frozen in liquid N2 or dry ice-cooled methanol. in FITC labels, or in light sources. When sections were air dried, 56 +/- 4% of the alkaline phosphatase stained vessels were marked with FITC label in brains frozen 20 sec after FITC injection. India ink labeled 89 +/- 7% of the alkaline phosphatase stained capillaries. When sections were air dried, 86 +/- 7% of the alkaline phosphatase stained vessels were labeled in brains frozen 6 min after injection of the FITC label. Using a technique of absolute alcohol impregnation of the sections, 130 +/- 25% and 144 +/- 28% of the alkaline phosphatase stained sections were FITC labeled. It can be concluded that the absolute alcohol impregnation technique significantly overestimates the number of perfused cerebral capillaries.

Alkaline Phosphatase↗
PubMed1993

Evaluation of the apical seal of amalgam retrofillings with the use of a root canal sealer interface.

The apical seal of amalgam retrograde fillings was evaluated in 86 extracted teeth. The experimental groups included retrofillings of amalgam alone, amalgam with a cavity varnish interface, and amalgam with a root canal sealer interface. After a 3-month immersion of the teeth in Higgins ink and subsequent clearing process, statistical analysis of ink penetration measurements showed significantly less leakage (p < 0.001) around amalgam retrofillings when using a root canal sealer as an interface between the retrograde cavity preparation and the condensed amalgam.

Dental Alloys↗
PubMed1994

Androgen deprivation prior to radical prostatectomy for T2b and T3 prostate cancer.

OBJECTIVE: In an effort to improve on the results of radical prostatectomy for clinical stages T2b and T3 prostate cancer, a selected group of patients received androgen deprivation for three to sixteen months prior to surgery. METHODS: Fifteen men with clinical T2b and 22 with small T3 tumors received a luteinizing hormone-releasing hormone analog (n = 34) or a bilateral orchiectomy (n = 3) three to sixteen months prior to radical retropubic prostatectomy. The prostate was evaluated with particular attention to tumor grade, presence of extracapsular extension, tumor at the inked margin, seminal vesicle invasion, and tumor in the lymph nodes. RESULTS: No patient had clinical or chemical (prostate-specific antigen [PSA]) progression during androgen deprivation. The PSA level declined a mean 90 percent and remained above 4 ng/mL in only two patients. The prostate volume decreased an estimated 30-50 percent. Prostate cancer at the inked margin was found in 15 (41%) and seminal vesicle involvement in 11 (30%) patients. Five (14%) had tumor in regional lymph nodes. There was no difference in regard to positive margins or lymph node metastases between those clinically staged as T2b and those preoperatively staged as T3. Fourteen patients have received adjuvant therapy (13 androgen deprivation, one radiation therapy). None has progressed (mean follow-up, 38.4 months). Of 23 who did not receive immediate additional therapy, six (26%) had progression, as was evident from an increase in PSA and have since been treated. Only one continued to progress. Thirty-five of the 37 patients are alive. Seventeen (46%) are tumor free (PSA < 0.4 ng/mL) without further androgen deprivation. CONCLUSIONS: Only a prospective randomized trial can determine whether androgen deprivation prior to radical prostatectomy has a role. The results from this trial are encouraging for several reasons. The prostate is much smaller as a result of androgen deprivation and this may facilitate surgery. Although the great majority of these patients were expected to be margin positive, 60 percent had negative margins and only 14 percent had positive lymph nodes.

Combined Modality Therapy↗
PubMed1984

The effects of PGF2 alpha, PGE2 and 16, 16 dimethyl PGE2 on gastric emptying and small intestinal transit in rat.

Prostaglandins are well known for their ability to stimulate contraction in gastrointestinal smooth muscle, yet very little information is available on how their activity affects propulsion in vivo. Thus, studies were undertaken to determine the effect of various prostaglandins on gastric emptying (GE) and small intestinal transit (SIT) in unanesthetized fasted rats. Rats were treated with intravenous, subcutaneous, or oral PGF2 alpha, PGE2, or 16, 16 dimethyl PGE2 at various doses, followed 1 (intravenous), 20 (subcutaneous) or 10 (oral) mins later by intragastric 51Cr oxide in black ink. Forty-five mins later, rats were sacrificed by CO2 asphyxiation, the pylorus clamped, and the gut excised. SIT was expressed as the percent of intestinal length traveled by the most distal portion of ink. GE was expressed as the percent of the 51Cr emptied into the intestines. If GE was affected by prostaglandin treatment, the experiments were repeated with rats pre-implanted with duodenal cannula. This preparation allowed the visual transit marker to be deposited directly into the duodenum, thus avoiding acceleration or delay of SIT caused by fluctuations in GE. The results of these studies show that: (1) intravenous 16, 16 dimethyl PGE2 (5-50 micrograms/kg), but not PGF2 alpha or PGE2, accelerates GE and delays SIT; (2) oral prostaglandin administration increases SIT; (3) oral 16, 16 dimethyl PGE2 delays GE; (4) subcutaneous 16, 16 dimethyl PGE2 accelerates, has no effect upon, or delays GE depending upon dose, but accelerates SIT at all doses tested; and (5) subcutaneous PGE2 accelerates SIT while PGF2 alpha does not. Thus, the effect of prostaglandins on GE and SIT depends upon the dosage and route of administration as well as type of prostaglandin used.

16,16-Dimethylprostaglandin E2↗
PubMedDate not supplied

Spectrophotometric determination of proteolytic activity in coloured solutions.

A simple procedure for spectrophotometric determination of proteolytic activity in coloured solutions is described. Gelatin cross-linked with glutaric dialdehyde or formaldehyde in the presence of black drawing ink is used as an insoluble chromolytic substrate. The absorbances of reaction mixture filtrates are read in the near infra-red region (at 800-900 nm) where the majority of coloured substances does not absorb; on the contrary black drawing ink released from the substrate during the proteolysis absorbs strongly even at these wavelengths.

Hydrolysis↗
PubMed1991

Spectrophotometric determination of amylase activity in coloured solutions.

A simple procedure for spectrophotometric determination of amylase activity in coloured solutions is described. Starch cross-linked with a bifunctional reagent in the presence of black drawing ink is used as an insoluble chromolytic substrate. The absorbances of reaction mixture filtrates are read in the near-infrared region (at 800-900 nm) where the majority of coloured substances does not absorb; on the contrary, black drawing ink released from the substrate during the action of amylase absorbs strongly even at these wavelengths.

Amylases↗
PubMed1986

Laminin immunohistochemistry: a simple method to visualize and quantitate vascular structures in the mammalian brain.

Immunohistochemistry using antiserum against the basement membrane glycoprotein laminin, was shown to be an excellent marker for brain blood vessels. Throughout the brain of mice, rats, guinea pigs, monkeys and humans, the basement membrane of the vascular structures were strongly laminin-positive. The neuropil itself was laminin-negative, whereas a positive reaction was observed in the meaninges. When the laminin antiserum was preabsorbed with its proper antigen, no specific fluorescence was observed. Using India ink perfusion as a comparative method, it was found that probably all vascular structures were also visualized with laminin immunohistochemistry. Laminin immunofluorescence was found well-suited for computer-assisted quantitative image analysis of brain vascularity. As expected in the periphery, the basement membrane of many other structures except blood vessels such as endoneurium, epithelium and smooth muscle cells were laminin-positive. Although the vascular network was also strongly laminin-immunoreactive, it was difficult to differentiate between blood vessels and non-vascular structures in the periphery as compared to the central nervous system. In conclusion, laminin immunohistochemistry has proven to be a simple, useful and specific method to study vascular structures in the central nervous system and an excellent alternative to more conventional and laborious methods such as perfusion with India ink.

Animals↗
PubMed1986

Extent of survival and vascularization of adult superior cervical sympathetic or nodose ganglia transplanted into the septal nuclei or choroid fissure of adult rats.

Adult superior cervical sympathetic ganglia were auto-transplanted, and adult nodose ganglia were homografted into the septal nuclei or the choroid fissure of adult Wistar rats. At times from 4 h to 9 weeks after operation, the distribution of surviving transplanted neurons was compared with the development of the transplant vascularization, as visualized by transcardial Indian ink filling of the host vascular system. Within 24 h, the ganglionic neurons and Schwann cells of the interior of the transplants in both sites were necrotic. The surviving neurons and Schwann cells formed a shell, occupying those areas of the transplant periphery which were in direct contact with the host circulation. Occasional ink-filled vessels were evident at this time in transplants in the choroid fissure, but there were none in the septal nuclei, where vessels did not appear until the next day. Blood vessels reached the centre of the ganglia by 3-4 days in the choroid fissure and one week in the septal nuclei, the finest diameter capillaries forming last. At longer survivals there was a slow loss of neurons, notable between 1 and 2 months, and leading progressively (especially in the septal transplantation site) to the disappearance of all but a very small number of ganglionic neurons. The general findings were similar for both types of ganglion, and in both sites, but the initial cell loss was much greater for both types of ganglia in the septum (over 90%) as compared with about a 50% loss in the choroid fissure. The initial rapid cell loss was probably a result of ischaemia. The subsequent, slow progressive loss may be associated with failure to make or receive neuronal connections, or the absence of appropriate growth factors.

Animals↗
PubMed1987

The clinical laboratory evaluation of cryptococcal infections in the acquired immunodeficiency syndrome.

The medical and laboratory records were reviewed in 37 acquired immunodeficiency syndrome (AIDS) patients with cryptococcal infections. In 24 patients with the presentation of cryptococcal meningitis, the initial cerebrospinal fluid (CSF) culture was positive. The initial India ink mount demonstrated organisms in 79% of culture positive CSF specimens. After therapy the subsequent India ink mounts demonstrated 84% sensitivity and 53% specificity with respect to culture outcome. Cultures of blood, bronchoalveolar lavage fluid, and brain were more likely to be positive than cultures from other sites. The initial blood cultures were positive in eight of eight patients at presentation of cryptococcal meningitis. When the initial CSF titer was greater than 1:2, the corresponding CSF culture was always positive. A negative culture during therapy did not necessarily indicate eradication of infection. The initial cerebrospinal fluid and serum cryptococcal antigen titers varied significantly and could not be correlated with survival. In three instances when the CSF cryptococcal antigen titers and cultures were negative, a positive serum cryptococcal antigen greater than 1:8 suggested disseminated infection.

Acquired Immunodeficiency Syndrome↗
PubMed2005

Inkjet printing of viable mammalian cells.

The purpose of this study was to explore the use of a commercial thermal printer to deposit Chinese Hamster Ovary (CHO) and embryonic motoneuron cells into pre-defined patterns. These experiments were undertaken to verify the biocompatibility of thermal inkjet printing of mammalian cells and the ability to assemble them into viable constructs. Using a modified Hewlett Packard (HP) 550C computer printer and an HP 51626a ink cartridge, CHO cells and rat embryonic motoneurons were suspended separately in a concentrated phosphate buffered saline solution (3 x). The cells were subsequently printed as a kind of "ink" onto several "bio-papers" made from soy agar and collagen gel. The appearance of the CHO cells and motoneurons on the bio-papers indicated an healthy cell morphology. Furthermore, the analyses of the CHO cell viability showed that less than 8% of the cells were lysed during printing. These data indicate that mammalian cells can be effectively delivered by a modified thermal inkjet printer onto biological substrates and that they retain their ability to function. The computer-aided inkjet printing of viable mammalian cells holds potential for creating living tissue analogs, and may eventually lead to the construction of engineered human organs.

Animals↗
PubMed2005

An amperometric glucose biosensor prototype fabricated by thermal inkjet printing.

The prototype of an amperometric glucose biosensor was realized by thermal inkjet printing using biological and electronic water-based inks, containing a glucose oxidase (GOD) from Aspergillus niger and the conducting polymer blend poly(3,4-ethylenedioxythiophene/polystyrene sulfonic acid) (PEDOT/PSS), respectively. The biosensor was fabricated microdepositing PEDOT/PSS and GOD, in sequence, on ITO-glass, by a commercial inkjet printer, with the help of a commercial software. High density microdots matrices were so-realized, with a calculated resolution of about 221 x 221 dpi (dot per inch). By means of a rapid and easy assay it was demonstrated that no activity loss occurred upon the printing of GOD, despite of the use of a thermal printhead. The device was encapsulated in a semipermeable membrane of cellulose acetate, applied by dip-coating, in order to prevent dissolution of the enzyme and/or PEDOT/PSS in water. The preliminary response of the electrode was measured in an aqueous glucose solution in the presence of ferrocenemethanol (FeMeOH) as a mediator, and resulted linear up to 60 mM in glucose. The best sensitivity value achieved was 6.43 microAM(-1) cm(-2) (447 nAM(-1) U(-1) cm(-2)). The characteristics of the device, and the possible performance improvements have been analyzed and discussed. The reported findings indicate that inkjet printing could be a viable instrument for the easy construction of a working biosensor via direct digital design using biological and conductive polymer based inks. Such an approach may be seen as an example of "biopolytronics".

Aspergillus niger↗
PubMed2005

Anatomy of the proximal cutaneous perforator vessels of the gracilis muscle.

An anatomic study was performed to analyse the proximal perforator vessels of the gracilis musculocutaneous flap. Twenty-three cadaver legs preserved by the method of Thiel were carefully dissected 24h after the proximal vascular pedicle was injected with a red silicone mass. Nine additional cadaver legs were injected with ink, to visualise the skin area supplied by the proximal perforators, respectively, clarified by a modified Spalteholz technique to demonstrate the anatomic course of the perforators. A considerable variation in numbers and localisation of proximal cutaneous perforators was found. One to four perforators were seen within an area of 6 x 6 cm(2) at the entrance of the main pedicle into the proximal gracilis muscle. Their external diameter ranged from 0.5 to 1.0 mm. The ink-injections showed an oval shaped angiosome with a mean surface of 88 cm(2) at the level of the proximal gracilis pedicle. We conclude from this anatomic study, that a cutaneous flap based on the medial circumflex femoral gracilis perforators can be harvested by experienced hands bearing in mind the unpredictable perforator-anatomy.

Arteries↗
PubMedDate not supplied

Laser treatment of tattoos.

Tattooing has been around since the early beginnings of modern civilization. Modern tattoo artists use a myriad of colors to produce striking designs, resulting in permanent works of body art; however, we humans have been changing our minds since the beginning of time. Our fickle nature results in the desire to change what has been placed as a permanent reminder of a friend, spouse, or work of art. Removing tattoos began with abrasive and destructive measures to destroy the tattoo, and unfortunately, the skin it was contained in. The discovery of selective photothermolysis, the ability to selectively remove target structures without disrupting the surrounding skin, made it at least possible to remove tattoos without destroying the surrounding skin leaving a scar. Theory predicted that pulse durations in the nanosecond domain would be optimal for tattoo removal, and the Q-switched neodymium:yttrium-aluminum-garnet, alexandrite, and ruby lasers fulfilled this need. Too often, older lasers or intense pulsed light sources are used to treat tattoos, often with significant scarring. Since the advent of the Q-switched lasers more than a decade ago, improvement in tattoo-removal lasers has been incremental. Developments leading to new tattoo inks, feedback systems to detect the absorbance characteristics of tattoo inks, dermal clearing agents, and perhaps even shorter pulse-duration lasers should result in improved results for the future.

Humans↗
PubMed2005

Correcting spatial distortion in histological images.

We described an interactive method for correcting spatial distortion in histology samples, applied them to a large set of image data, and quantitatively evaluated the quality of the corrections. We demonstrated registration of histology samples to photographs of macroscopic tissue samples and to MR images. We first described methods for obtaining corresponding fiducial and anatomical points, including a new technique for determining boundary correspondence points. We then describe experimental methods for tissue preparation, including a technique for adding color-coded internal and boundary ink marks that are used to validate the method by measuring the registration error. We applied four different transformations with internal and boundary correspondence points, and measured the distance error between other internal ink fiducials. A large number of boundary points, typically 20-30, and at least two internal points were required for accurate warping registration. Interior errors with the transformation methods were ordered: thin plate spline (TPS) approximately non-warping<<triangle warping<polynomial warping. Although non-warping surprisingly gave the lowest interior distance error (0.5+/-0.3mm), TPS was more robust, gave an insignificantly greater error (0.6+/-0.3mm) and much better results near boundaries where distortion was more evident, and allowed us to correct torn histology samples, a common problem. Using the method to evaluate RF thermal ablation, we found good zonal correlation between MR images and corrected histology samples. The method can be practically applied to this and other emerging applications such as in vivo molecular imaging.

Algorithms↗
PubMed2004

Intraoperative margin assessment and re-excision rate in breast conserving surgery.

AIM: The aim of this study was to assess the efficacy of intraoperative margin assessment in obtaining clear margins in conserving surgery for breast cancer. METHODS: Two hundred and twenty patients undergoing wide local excision (WLE) for core biopsy proven primary invasive breast cancer, during a 30 months period, were included in the study. Following surgical excision the breast specimen was orientated with sutures, inked using India ink and coloured pigments and incised to identify the tumour, maintaining orientation. The distance to the individual radial margins were estimated macroscopically by the pathologist and conveyed intraoperatively to the surgeon. A macroscopic tumour-margin distance of less than 10 mm was considered compromised and the margin(s) in question was then excised if feasible. RESULTS: Eighty-one patients (37%) were judged to have compromised margins following intraoperative macroscopic evaluation and had at least one margin re-excised. Sixteen of the 81 patients (20%) in this subgroup had compromised margins on microscopy and required a second operation. One hundred and thirty-nine patients (63%) were deemed to have clear margins intraoperatively, subsequently confirmed on microscopic examination in 135 patients (97%). Intraoperative macroscopic assessment of margin status was associated with 9.1% of patients requiring a second operation. In the absence of intraoperative assessment of margin status a further 47 patients (21.4%) would have required a second operation. CONCLUSION: Intraoperative macroscopic margin assessment is an effective technique in reducing the number of second operative procedures in patients undergoing conserving surgery for primary invasive breast cancer.

Breast Neoplasms↗