Biomedical subjects

Y Fujino

Publications and source records attributed to Y Fujino.

At least 55 records · Page 3Linked to original sources

PubMed2000

Enhanced phospholipase C activity in the cultured skin fibroblast obtained from patients with coronary spastic angina: possible role for enhanced vasoconstrictor response.

OBJECTIVES: We measured phospholipase C (PLC) activity in the cultured skin fibroblasts obtained from patients with and without coronary spasm and examined its correlation with coronary artery vasomotility. BACKGROUND: Coronary artery vasomotility is enhanced in coronary spastic angina (CSA), but no information is available for the intracellular signaling. In spontaneously hypertensive rats, PLC activity in the skin fibroblasts has been shown to be enhanced. METHODS: Skin fibroblasts obtained from 24 patients with CSA-14 with organic coronary artery disease (CAD) and 12 control subjects--were cultured by the explant method. Activity of PLC was determined by incubating the membrane fraction with 3H-phosphatidyl inositol bisphosphate and by quantifying 3H-inositol trisphosphate. In patients with CSA and control subjects, the relations between PLC activity and coronary artery basal tone and constrictor response to intracoronary acetylcholine (ACh) were examined. RESULTS: Activity of PLC (pmol/protein [mg] per min) was 1.74+/-0.19 in patients with CSA; 0.90+/-0.12 in patients with CAD; and 0.65+/-0.07 in control subjects (p<0.001, patients with CSA vs. patients with CAD and control subjects; p = NS, patients with CAD vs. control subjects). According to the Lineweaver-Burk plot, Michaelis constant (micromol/liter) of PLC was 28+/-4 in patients with CSA; 49+/-14 in patients with CAD; and 56+/-10 in control subjects (p<0.05, patients with CSA vs. control subjects), whereas the maximal velocity was not different between the three groups. There were significant positive correlations between PLC activity and both basal tone (p = 0.0108) and response to ACh (p = 0.0053). Western blot analysis using membrane fraction demonstrated that 89% of PLC isoenzymes detected was of the delta1 isoform. CONCLUSIONS: Because the PLC activity measured was genetically defined and was positively correlated with coronary artery vasomotility, enhanced PLC activity may be involved in the pathogenesis of coronary spasm.

Angina Pectoris, Variant↗

PubMed2000

Evolution, structure, and expression of GNPI/Oscillin orthologous genes.

Oscillin was identified from hamster sperm as a factor responsible for oocyte calcium oscillations. However, its high level of homology with the bacterial glucosamine-6-phosphate isomerase suggests that it may play more fundamental roles. In the current study, we identified Oscillin orthologs from Caenorhabditis elegans, Drosophila melanogaster, mouse, and human. Their amino acid identities with hamster oscillin were 67.0, 72.3, 97.6, and 95.5%, respectively. No Oscillin orthologs were found in Saccharomyces cerevisiae. The human Oscillin gene (HGMW-approved symbol GNPI) spans 12.4 kb and consists of eight exons. The position of the fourth intron was conserved in other species. The human Oscillin promoter has features characteristic of housekeeping genes, including a GC-rich content, multiple SP1 binding sites, and the absence of a TATA motif. Human and mouse Oscillin genes were ubiquitously expressed in all tissues examined. These data showed that Oscillin is a housekeeping gene conserved throughout evolution and do not support the notion that Oscillin is the sperm-specific factor responsible for calcium oscillations.

Aldose-Ketose Isomerases↗

PubMed2000

Different expression of calreticulin and immunoglobulin binding protein in Alzheimer's disease brain.

Both calreticulin (CRT) and immunoglobulin binding protein (Bip) have a role in the folding and assembly of oligomeric membrane proteins in the endoplasmic reticulum (ER). Recent studies have demonstrated the generation of beta-amyloid protein (Abeta) 1-42, a key peptide for amyloid deposits, in the ER. We, therefore, examined the localization and expression of CRT, Bip and their mRNA by immunohistochemistry, Western blot, in situ hybridization and semiquantitative reverse transcription polymerase chain reaction (RT-PCR) in both neurologically normal and Alzheimer's disease (AD) brains. Two polyclonal anti-CRT antibodies gave similar positive staining of CRT in neurons and glia. In neuronal cells, the cytoplasm, nucleoli and their processes were positive for CRT. In glial cells, perinuclear staining was frequently seen and the processes of some glial cells were also stained. In AD, these antibodies stained clearly damaged neurons but the number and the intensity of positive cells were decreased compared to controls. Processes of microglial cells were markedly positive in the AD white matter. Western blots using an anti-CRT antibody showed significantly lower immunoreactive bands in AD than control brains. By in situ hybridization, the number of neurons which express the CRT mRNA was less in AD than in controls. Using RT-PCR, the relative levels of the CRT mRNA in AD brains were also found to be significantly lower than those in controls. On the other hand, the number of Bip-positive cell, the production of Bip and the expression of mRNA for Bip did not differ between control and AD brains. These results suggest that CRT may be a multifunctional protein in human brain, and that the weak expression of CRT and the positive staining of microglial processes in AD brain may be part of the pathological processes in AD.

Aged↗

PubMed2000

Intussusception due to vanishing colon cancer with metastasis of the regional lymph nodes: report of a case.

We present herein a case report of vanishing colon cancer with intussusception. A 70-year-old man with hematochezia was admitted to our hospital. Preoperative images showed ileus due to a colonic tumor. At operation, normograde intussusception without any tumor was recognized at the sigmoid colon. Interestingly, the regional lymph nodes were found to be invaded by tubular adenocarcinoma cells, thus suggesting that the colon cancer existed before the necrosis of the wall took place.

Adenocarcinoma↗

PubMed2000

Bilateral choroidal metastases secondary to uterocervical carcinoma of the squamous cell type.

PURPOSE: To report a patient with bilateral choroidal metastases secondary to uterocervical carcinoma of the squamous cell type. METHODS: Case report. RESULTS: A 55-year-old woman complained of visual field loss and decreasing vision. Seven months earlier, uterocervical carcinoma of the squamous cell type was diagnosed and treated with chemotherapy and irradiation. Serous retinal detachment and choroidal masses were present in both eyes. Retinal detachment was lessened in both eyes after radiotherapy. The patient died of respiratory insufficiency 3 months after the appearance of choroidal metastases. At autopsy, there was no second cancer to cause the choroidal metastases. Tumor embolization was present in the choriocapillaries. CONCLUSION: Choroidal metastasis may develop from hematogenous spread of uterocervical squamous cell carcinoma.

Carcinoma, Squamous Cell↗

PubMed2000

Chairpersons' opinions regarding quality control of surgical faculty performance in Japanese academic surgery departments.

BACKGROUND: The governance and power structure of the department of surgery depends to a large extent on the chairperson's decisions in Japanese medical schools. This paper reports the current collective opinions of surgery department chairpersons regarding the quality assessment of surgical faculty performance. METHODS: Surveyed were 78 chairpersons of general surgery departments from 72 Japanese medical schools. Chairpersons were questioned about administrative and organizational decision making: rank order requirements for full-time surgical faculties, coordination of staff for surgical operations, and performance outcome measures. RESULTS: In all, 68 (87%) chairpersons responded. When selecting surgical faculties, publishing competence (45%) and collaborative personality (44%) were the two foremost concerns of chairpersons. Teaching experience (0%) and board certification (2%) showed the lowest rate for the first priority among the 6 elements listed. The operator was mainly decided by the chairperson (63%) whereas the rest of the operative team members were decided by either the chairperson (28%), a specialty team (38%), or attending surgeons (32%). Thirty-three chairpersons (49%) of 68 respondents used the morbidity and mortality conference as the only available approach for assessing surgical performance on a regular basis, whereas the remaining half did not have routine outcome measures. CONCLUSIONS: The results of this study indicate that surgery department chairpersons deemed collaborative personality and publishing competence the two major requirements for candidates of surgical faculties. Although the morbidity and mortality conference is currently the only available approach for assessing surgical performance, the majority of chairpersons felt that outcome measures should be based on more objective and structured criteria.

Academic Medical Centers↗

PubMed2000

Analysis of liquid accumulated in the distended capsular bag in early postoperative capsular block syndrome.

PURPOSE: To analyze the transparent liquid between the posterior lens capsule and the posterior chamber intraocular lens (PC IOL) in early postoperative capsular block syndrome and discuss the mechanism of posterior capsule distention. SETTING: Department of Ophthalmology, Tokyo University School of Medicine, and Tokyo Research Institute, Seikagaku Corporation, Tokyo, Japan. METHODS: This study evaluated 3 cases of capsular block syndrome presenting with transparent liquid in the distended capsular bag 1 day after cataract surgery. The transparent liquid material between the posterior capsule and PC IOL was aspirated and analyzed using high-performance liquid chromatography (HPLC). Also, sodium hyaluronate was diluted using a dialyzer to determine whether the aqueous humor was drawn into the capsular bag by an osmotic gradient across the capsule. RESULTS: The elution time of the samples was almost the same as that of sodium hyaluronate 1.0% (Healon) The concentration of the samples ranged from 3.29 to 9. 01 mg/mL by HPLC analysis. The sodium hyaluronate absorbed the physiological salt solutions through the dialyzer and expanded to 1. 9 times its original volume. CONCLUSIONS: These results indicate that the main ingredient of the transparent liquid in capsular bags is sodium hyaluronate and that the distention is caused by aqueous humor being drawn into the capsular bag by an osmotic gradient across the capsule when the capsulorhexis diameter is smaller than that of the PC IOL and by viscoelastic material retained and trapped in the bag intraoperatively.

Aged↗

PubMed2000

Localization of a novel type trypsin-like serine protease, neurosin, in brain tissues of Alzheimer's disease and Parkinson's disease.

Neurosin, a novel type of trypsin-like serine protease, has been shown to be preferentially expressed in human brain by northern blotting. We examined neurosin immunolabeling in the brains of neurologically normal persons and patients with Alzheimer's disease (AD) and with Parkinson's disease. We also identified the expression of the mRNA for neurosin by in situ hybridization histochemistry and reverse transcription-polymerase chain reaction (RT-PCR). The neurosin antibody stained all of the nuclei of various cell types. In neurons, there was also staining of neuronal cytoplasm, nucleoli and their processes. In AD, staining of neurons with processes was rare in the damaged areas. Some senile plaques, extracellular tangles and Lewy bodies were also positive for neurosin. Expression of the mRNA for neurosin was seen in neurons in the gray matter, and in microglial cells in the white matter. In AD, the intensity of the signal for neurosin mRNA in the gray matter was decreased compared with normal control brains. The relative levels of neurosin mRNA in AD brains, measured by RT-PCR, were lower than those in controls. These results suggest that in human brain neurosin plays various physiological roles, and that in AD this molecule, like other serine proteases, may have a role in the degradation of such substances as beta-amyloid protein.

Aged↗

PubMed2000

Sildenafil is a pulmonary vasodilator in awake lambs with acute pulmonary hypertension.

BACKGROUND: Phosphodiesterase type 5 (PDE5) hydrolyzes cyclic guanosine monophosphate in the lung, thereby modulating nitric oxide (NO)/cyclic guanosine monophosphate-mediated pulmonary vasodilation. Inhibitors of PDE5 have been proposed for the treatment of pulmonary hypertension. In this study, we examined the pulmonary and systemic vasodilator properties of sildenafil, a novel selective PDE5 inhibitor, which has been approved for the treatment of erectile dysfunction. METHODS: In an awake lamb model of acute pulmonary hypertension induced by an intravenous infusion of the thromboxane analog U46619, we measured the effects of 12.5, 25, and 50 mg sildenafil administered via a nasogastric tube on pulmonary and systemic hemodynamics (n = 5). We also compared the effects of sildenafil (n = 7) and zaprinast (n = 5), a second PDE5 inhibitor, on the pulmonary vasodilator effects of 2.5, 10, and 40 parts per million inhaled NO. Finally, we examined the effect of infusing intravenous l-NAME (an inhibitor of endogenous NO production) on pulmonary vasodilation induced by 50 mg sildenafil (n = 6). RESULTS: Cumulative doses of sildenafil (12.5, 25, and 50 mg) decreased the pulmonary artery pressure 21%, 28%, and 42%, respectively, and the pulmonary vascular resistance 19%, 23%, and 45%, respectively. Systemic arterial pressure decreased 12% only after the maximum cumulative sildenafil dose. Neither sildenafil nor zaprinast augmented the ability of inhaled NO to dilate the pulmonary vasculature. Zaprinast, but not sildenafil, markedly prolonged the duration of pulmonary vasodilation after NO inhalation was discontinued. Infusion of l-NAME abolished sildenafil-induced pulmonary vasodilation. CONCLUSIONS: Sildenafil is a selective pulmonary vasodilator in an ovine model of acute pulmonary hypertension. Sildenafil induces pulmonary vasodilation via a NO-dependent mechanism. In contrast to zaprinast, sildenafil did not prolong the pulmonary vasodilator action of inhaled NO.

15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5↗

PubMed2000

Optimal level of pressure support ventilation for recovery from diaphragmatic fatigue in rabbits.

OBJECTIVE: To determine whether there is an optimal level of pressure support ventilation (PSV) for recovery from acute diaphragmatic fatigue. DESIGN: Prospective laboratory trial. SETTING: Experimental laboratory. SUBJECTS: Twenty healthy adult New Zealand White rabbits. INTERVENTIONS: Diaphragmatic fatigue was induced with 50 Hz of phrenic nerve stimulation for 30 mins. Recovery was compared between inspiratory load + PSV of 0 cm H2O (L0), inspiratory load + PSV of 60 cm H2O (L60), inspiratory load + PSV of 80 cm H2O (L80), and PSV of 0 cm H2O without inspiratory load (SB) for 90 mins immediately after the end of the fatigue-inducing procedure. To add inspiratory load during the recovery phase, three pressure threshold valves, each having an opening pressure of -20 cm H2O, were used. MEASUREMENTS AND MAIN RESULTS: After the fatigue-inducing procedure, diaphragmatic electromyogram and transdiaphragmatic pressure remained at baseline in both SB and L60, decreased in L80, and increased in L0. Recovery was assessed by abdominal cavity pressure (Pabd) generated by high-frequency (100 Hz) and low-frequency (20 Hz) stimulation. Pabd at 100 Hz recovered to baseline in L60 and SB but not in L0 and L80 (69.1%, 81.3%, 100.3%, and 100.7% of the baseline at 90 mins for L0, L80, L60, and SB, respectively). Pabd at 20 Hz did not differ among ventilatory settings. CONCLUSION: There is an optimal range of PSV assist level to improve recovery from diaphragmatic fatigue. Recovery was hampered not only by inadequate PSV but also by excessive PSV.

Airway Resistance↗

PubMed2000

Evidence of protein synthesis during resuscitation of ischemically damaged canine pancreas by the two-layer method.

The two-layer method, which supplies sufficient oxygen to the canine pancreas graft and allows adenotriphosphate synthesis within the graft, resuscitates the ischemically damaged pancreas graft during mild hypothermic (20 degrees C) preservation, but the mechanisms are unknown. The purpose of this study was to determine whether protein synthesis was performed on ischemically damaged pancreas graft during preservation by the two-layer method in a canine autotransplantation model. The pancreas grafts subjected to 90 minutes of warm ischemia were preserved by the two-layer method (perfluorochemical/University of Wisconsin solution) at 20 degrees C for 5 hours. Graft viability was judged from graft survival after autotransplantation. DNA, RNA, and protein synthesis was quantitated by determining incorporation of tritiated thymidine, tritiated uridine, and tritiated leucine, respectively, during preservation. Significant increases in RNA and subsequent protein syntheses were observed during preservation by the two-layer method. In contrast, DNA synthesis did not follow RNA and protein synthesis. We conclude that protein is synthesized in the process of postischemic cellular recovery of the pancreas graft during mild hypothermic preservation by the two-layer method.

Animals↗

PubMed2000

Superiority of mild hypothermic (20 degrees C) preservation for pancreatic microvasculature using the two-layer storage method.

Hypothermia causes vascular endothelial damage that leads to graft microcirculation disorder and eventually thrombosis after reperfusion. The two-layer cold storage method (TL) was previously demonstrated to supply oxygen to the pancreas graft and maintain high adenosine triphosphate tissue concentration. In this study, we evaluated whether mild hypothermic (20 degrees C) preservation using the TL method could reduce endothelial damage while maintaining parenchymal viability. Graft survival by 20 degrees C preservation was investigated using a dog segmental pancreas autotransplantation model (simple storage in University of Wisconsin solution (UW) for 5 and 8 hours or TL for 5, 8, 12, and 24 hrs. respectively). Subsequently, the grafts were preserved in four different conditions (4 and 20 degrees C UW. 4 and 20 degrees C TL) for 8 hours to evaluate microvascular endothelial damage. Trypan blue uptake of vascular endothelium and pancreatic tissue perfusion were evaluated. No graft preserved by 20 degrees C UW for 5 and 8 hours survived (0/7 and 0/4). In contrast, the graft survival rates by 20 degrees C TL for 5, 8, 12, and 24 hours were 100% (5/5), 80% (4/5), 20% (1/5), and 0% (0/4), respectively. In trypan blue uptake analysis, there were significant differences between 4 and 20 degrees C in both UW and TL (4 degrees C UW, 37% [n = 5) vs. 20 degrees C UW, 13% [n = 4] [p < 0.01]; 4 degrees C TL, 29% [n = 5] vs. 20 degrees C TL, 10% [n = 5] [p < 0.011). The perfusion values in 20 degrees C TL were significantly higher than those in other groups at least for up to 120 minutes after reperfusion (p < 0.01 ). In short-term pancreas preservation, mild hypothermic TL reduced vascular endothelial cell damage and ameliorated graft microcirculation while maintaining parenchymal viability. Mild hypothermic TL may lessen vascular complications in clinical pancreas transplantation when used for several-hour preservation.

Animals↗

PubMed2000

Control of major hemorrhage from the spleno-mesenteric vein junction during pancreaticoduodenectomy: successful use of an occlusion balloon catheter.

BACKGROUND/AIMS: Vascular disruption is sometimes associated with intractable hemorrhage due to either vessel fragility or increased blood flow rates in patients with chronic pancreatitis during surgical operation. This paper describes the successful use of an occlusion catheter for repairing a major laceration at the spleno-mesenteric vein junction. METHODS: A 14-Fr Fogarty occlusion balloon catheter was directly inserted into the splenic vein through the site of venous laceration and inflated to stop blood flow from the splenic vein. RESULTS: This procedure perfectly controlled massive hemorrhage from the spleno-mesenteric vein junction. The injured site was repaired with a continuous suture in 5 min. CONCLUSION: The direct insertion of a balloon catheter to the injured site is simple and expeditious to control major hemorrhage from the spleno-mesenteric vein junction when the situation is otherwise unmanageable.

Catheterization↗

PubMed2000

Partial liquid ventilation ventilates better than gas ventilation.

Partial liquid ventilation (PLV) improves oxygenation in several models of lung injury. However, PLV has only been compared with conventional gas ventilation (GV) with low PEEP. Both PLV and GV can markedly improve oxygenation when PEEP is set above the lower corner pressure (Plc) on the inspiratory pressure-volume (P-V) curve of the total respiratory system. We questioned if the use of PEEP set above the Plc during PLV and GV would result in similar gas exchange. Lung injury was induced in 12 sheep by saline lavage before randomization to PLV (n = 6) or GV (n = 6). Animals in the PLV group were filled with perflubron (22 ml/kg) until a meniscus at the teeth was observed. Both groups were then ventilated with pressure control (FI(O(2)), 1.0; rate, 20/min; I:E, 1:1) and PEEP (1 cm H(2)O above the Plc on the inspiratory P-V curve). Peak inspiratory pressure (PIP) was limited to 35 cm H(2)O. Animals were ventilated for 5 h and then killed for histologic examinations. All 12 animals survived the 5-h ventilation period. After increasing PEEP above Plc, Pa(O(2)) increased significantly (p < 0.01) in both the GV and the PLV groups, but it did not differ significantly between groups (p = 0.86) at any time during the experiment. Pa(CO(2)) and VD/VT in GV increased markedly throughout the experiment after increasing PEEP (p < 0.001), but there was no significant change in Pa(CO(2)) in PLV (p = 0.13). Mean arterial blood pressure, mean pulmonary artery pressure, pulmonary artery occlusion pressure, and central venous pressure, increased and SVR decreased in GV (p < 0.05). The extent and the severity of lung injury in the dependent regions was greater in the GV group (p < 0.05). Both PLV and GV improved oxygenation, but PLV resulted in better ventilation than GV while preserving lung structure when PEEP was set 1 cm H(2)O above the Plc and PIP limited to 35 cm H(2)O.

Animals↗

PubMed2000

Surface active properties of simple cyclic and heterocyclic amines in water.

The surface tension of aqueous solutions of simple cyclic, heterocyclic and aromatic amines was measured with a Du Nöuy tensiometer at 25 degrees C and the results discussed in terms of structure-aggregation relationships. The simple compounds used in this study were piperazine, piperidine, morpholine, 3-methylpyridine, cyclohexylamine and benzylamine, with carbon numbers ranging from four to seven. Piperazine, piperidine and morpholine did not form micellar associations but cyclohexylamine, benzylamine and 3-methylpyridine did, indicating that more than six carbons are necessary to form micellar associations, at least for compounds having a six-membered ring.

Amines↗

PubMed2000

Synthesis and potato cell expansion-inducing activity of the stereochemically restricted bicyclic analogue of 7-epi-jasmonic acid.

The stereochemically restricted bicyclic analogue of 7-epi-jasmonic acid was synthesized from a known bicyclo[3.3.0]octane derivative. The enol triflate derived from the bicyclic compound was subjected to palladium-catalyzed coupling with allyltributyltin to give the desired carbon skeleton. Selective catalytic hydrogenation and subsequent acidic hydrolysis gave a new bicyclic analogue of 7-epi-jasmonic acid. The ACC conjugate of the bicyclic analogue was also synthesized. This ACC conjugate exhibited only slightly weaker potato cell expansion-inducing activity than that of the JA standard.

Biochemistry↗

PubMed2000

Clonality analysis of various hematopoietic disorders in cats naturally infected with feline leukemia virus.

The clonality analysis of the bone marrow cells was carried out by detecting the integrated proviruses of feline leukemia virus (FeLV) to understand the pathogenesis of FeLV-associated hematopoietic disorders in cats. Bone marrow cells from 4 cases with acute myeloid leukemia (AML), 9 cases with myelodysplastic syndromes (MDS), 2 cases with pure red cell aplasia (PRCA) and 3 healthy carriers infected with FeLV were subjected to Southern blot analyses using an exogenous FeLV probe. Clonal hematopoiesis was found in all the cases with AML and in 6 of the 9 cases with MDS, but not in the cases with both PRCA and healthy carriers infected with FeLV. In the 2 cases with MDS, it was thought that the same clones of the hematopoietic cells might proliferate before and after the progression of the disease irrespective of the changes of the hematological diagnoses by cytological examination. This study indicates that MDS in cats is a disease manifestation as a result of clonal proliferation of hematopoietic cells and can be recognized as a pre-leukemic state of AML.

Animals↗

PubMed2000

The relationship between gas delivery patterns and the lower inflection point of the pressure-volume curve during partial liquid ventilation.

STUDY QUESTION: To determine whether a positive end-expiratory pressure (PEEP) level equivalent to the lower inflection point (LIP) could be identified by evaluation of the airway pressure, flow (f1. gif" BORDER="0">), and volume vs time waveforms during partial liquid ventilation (PLV). DESIGN: Prospective application of PEEP during PLV in a healthy animal model. SETTING: University hospital animal laboratory. PARTICIPANTS: Five healthy sheep weighing 30 kg each. INTERVENTIONS: The sequential application of 0 to 20 cm H(2)O PEEP in 2.5-cm H(2)O steps during PLV with both pressure and volume ventilation. MEASUREMENTS: Analysis of the pressure, volume, and f1. gif" BORDER="0"> waveforms as PEEP is sequentially increased. RESULTS: At 0 cm H(2)O PEEP, VT was markedly reduced compared with PEEP VT at > or = 7.5 cm H(2)O (p < 0.05) in pressure control ventilation (PCV), and peak inspiratory pressure minus PEEP was markedly increased compared with PEEP at > or = 5.0 cm H(2)O (p < 0.05) in volume control ventilation. At 10 cm H(2)O PEEP, all waveforms began to stabilize, and no significant differences in any variable assessed were measured at > 12.5 cm H(2)O PEEP. CONCLUSIONS: The application of PEEP during PLV markedly alters airway waveforms. Low PEEP decreases VT in PCV and increases airway pressure in VCV. The PEEP level equal to the LIP during PLV can be grossly estimated from airway waveforms. PEEP at > or = 10 cm H(2)O is needed to normalize gas delivery to functional residual capacity in the uninjured lung that is partially filled with perfluorocarbon.

Air Pressure↗