Remote Mesoscopic Signatures of Induced Magnetic Texture in Graphene.

Mesoscopic conductance fluctuations are a ubiquitous signature of phase-coherent transport in small conductors, exhibiting universal character independent of system details. In this Letter, however, we demonstrate a pronounced breakdown of this universality, due to the interplay of local and remote phenomena in transport. Our experiments are performed in a graphene-based interaction-detection geometry, in which an artificial magnetic texture is induced in the graphene layer by covering a portion of it with a micromagnet. When probing conduction at some distance from this region, the strong influence of remote factors is manifested through the appearance of giant conductance fluctuations, with amplitude much larger than e^{2}/h. This violation of one of the fundamental tenets of mesoscopic physics dramatically demonstrates how local considerations can be overwhelmed by remote signatures in phase-coherent conductors.

Evaluation of clinical coding data to determine causes of critical bleeding in patients receiving massive transfusion: a bi-national, multicentre, cross-sectional study.

OBJECTIVES: To evaluate the use of routinely collected data to determine the cause(s) of critical bleeding in patients who receive massive transfusion (MT). BACKGROUND: Routinely collected data are increasingly being used to describe and evaluate transfusion practice. MATERIALS/METHODS: Chart reviews were undertaken on 10 randomly selected MT patients at 48 hospitals across Australia and New Zealand to determine the cause(s) of critical bleeding. Diagnosis-related group (DRG) and International Classification of Diseases (ICD) codes were extracted separately and used to assign each patient a cause of critical bleeding. These were compared against chart review using percentage agreement and kappa statistics. RESULTS: A total of 427 MT patients were included with complete ICD and DRG data for 427 (100%) and 396 (93%), respectively. Good overall agreement was found between chart review and ICD codes (78·3%; κ = 0·74, 95% CI 0·70-0·79) and only fair overall agreement with DRG (51%; κ = 0·45, 95% CI 0·40-0·50). Both ICD and DRG were sensitive and accurate for classifying obstetric haemorrhage patients (98% sensitivity and κ > 0·94). However, compared with the ICD algorithm, DRGs were less sensitive and accurate in classifying bleeding as a result of gastrointestinal haemorrhage (74% vs 8%; κ = 0·75 vs 0·1), trauma (92% vs 62%; κ = 0·78 vs 0·67), cardiac (80% vs 57%; κ = 0·79 vs 0·60) and vascular surgery (64% vs 56%; κ = 0·69 vs 0·65). CONCLUSION: Algorithms using ICD codes can determine the cause of critical bleeding in patients requiring MT with good to excellent agreement with clinical history. DRG are less suitable to determine critical bleeding causes.

Thermally Assisted Nonvolatile Memory in Monolayer MoS2 Transistors.

We demonstrate a novel form of thermally-assisted hysteresis in the transfer curves of monolayer MoS2 FETs, characterized by the appearance of a large gate-voltage window and distinct current levels that differ by a factor of ∼102. The hysteresis emerges for temperatures in excess of 400 K and, from studies in which the gate-voltage sweep parameters are varied, appears to be related to charge injection into the SiO2 gate dielectric. The thermally-assisted memory is strongly suppressed in equivalent measurements performed on bilayer transistors, suggesting that weak screening in the monolayer system plays a vital role in generating its strongly sensitive response to the charge-injection process. By exploiting the full features of the hysteretic transfer curves, programmable memory operation is demonstrated. The essential principles demonstrated here point the way to a new class of thermally assisted memories based on atomically thin two-dimensional semiconductors.

Probing weak localization in chemical vapor deposition graphene wide constriction using scanning gate microscopy.

Low-temperature scanning gate microscopy (LT-SGM) studies of graphene allow one to obtain important spatial information regarding coherent transport such as weak localization (WL) and universal conductance fluctuations. Although fascinating LT-SGM results on pristine graphene prepared by mechanical exfoliation have been reported in the literature, there appears to be a dearth of LT-SGM results on chemical vapor deposition (CVD)-grown graphene whose large scale and flexible substrate transferability make it an ideal candidate for coherent electronic applications. To this end, we have performed LT-SGM studies on CVD-grown graphene wide constriction (0.8 µm), which can be readily prepared by cost-effective optical lithography fully compatible with those in wafer foundry, in the WL regime. We find that the movable local gate can sensitively modulate the total conductance of the CVD graphene constriction possibly due to the intrinsic grain boundaries and merged domains, a great advantage for applications in coherent electronics. Moreover, such a conductance modulation by LT-SGM provides an additional, approximately magnetic-field-independent probe for studying coherent transport such as WL in graphene and spatial conductance variation.

Tuning surface grafting density of CeO2 nanocrystals with near- and supercritical solvent characteristics.

In this work, the solvent effect on the synthesis of CeO2 nanocrystals synthesized in near- and supercritical alcohols is discussed. The materials prepared displayed a unique morphology of small nanocrystals (<10 nm) aggregated into larger nanospheres (∼100-200 nm). In such syntheses, alcohol molecules directly interact with the nanocrystal surface through alkoxide and carboxylate bondings. The grafting density was quantified from the weight loss measured using thermogravimetric analysis. A direct correlation between the grafting density and the alcohol chain length can be established. It was demonstrated that the shorter the alcohol chain length (i.e. methanol), the higher the surface coverage is. This trend is independent of the synthesis mode (batch or continuous). Additionally, an influence of the grafting density on the resulting nanocrystal size was established. It is suggested that the surface coverage has a high influence on the early stages of the nucleation and growth. Indeed, when high surface coverages are reached, all surface active sites are blocked, limiting the growth step and therefore leading to smaller particles. This effect was noticed with the materials prepared in the continuous mode where shorter reaction time was performed.

Conduction Mechanisms in CVD-Grown Monolayer MoS2 Transistors: From Variable-Range Hopping to Velocity Saturation.

We fabricate transistors from chemical vapor deposition-grown monolayer MoS2 crystals and demonstrate excellent current saturation at large drain voltages (Vd). The low-field characteristics of these devices indicate that the electron mobility is likely limited by scattering from charged impurities. The current-voltage characteristics exhibit variable range hopping at low Vd and evidence of velocity saturation at higher Vd. This work confirms the excellent potential of MoS2 as a possible channel-replacement material and highlights the role of multiple transport phenomena in governing its transistor action.

Tuning the Fano resonance with an intruder continuum.

Through a combination of experiment and theory we establish the possibility of achieving strong tuning of Fano resonances (FRs), by allowing their usual two-path geometry to interfere with an additional, "intruder", continuum. As the coupling strength to this intruder is varied, we predict strong modulations of the resonance line shape that, in principle at least, may exceed the amplitude of the original FR itself. For a proof-of-concept demonstration of this phenomenon, we construct a nanoscale interferometer from nonlocally coupled quantum point contacts and utilize the unique features of their density of states to realize the intruder. External control of the intruder coupling is enabled by means of an applied magnetic field, in the presence of which we demonstrate the predicted distortions of the FR. This general scheme for resonant control should be broadly applicable to a variety of wave-based systems, opening up the possibility of new applications in areas such as chemical and biological sensing and secure communications.

Fast energy relaxation of hot carriers near the Dirac point of graphene.

We investigate energy relaxation of hot carriers in monolayer and bilayer graphene devices, demonstrating that the relaxation rate increases significantly as the Dirac point is approached from either the conduction or valence band. This counterintuitive behavior appears consistent with ideas of charge puddling under disorder, suggesting that it becomes very difficult to excite carriers out of these localized regions. These results therefore demonstrate how the peculiar properties of graphene extend also to the behavior of its nonequilibrium carriers.

EGFR inhibitors augment antitumour helper T-cell responses of HER family-specific immunotherapy.

BACKGROUND: Head and neck squamous cell carcinoma (HNSCC) is a major cause of cancer-related morbidity and mortality worldwide. Epidermal growth factor receptor (EGFR)-targeted therapy is an attractive strategy alternative to conventional cancer treatments for HNSCC, but its efficacy remains controversial. T-cell-based immunotherapy has been proposed as a novel therapeutic approach to improve the clinical outcome for HNSCC. In this study, we report human epidermal receptor (HER) family epitopes that induced CD4 T-cell responses to HNSCC. The results provide support for a novel strategy to treat HNSCC by combining EGFR-targeted therapy with T-cell-based immunotherapy. METHODS: We evaluated the capacity of predicted CD4 T-cell peptide epitopes from EGFR to induce antitumour immune responses in vitro. In addition, EGFR inhibitors were evaluated for their ability to augment tumour MHC class II expression in HNSCC cell lines and subsequently increase T-cell recognition. RESULTS: Among several predicted peptide epitopes, EGFR875-889 elicited CD4 T-cell responses that were restricted by HLA-DR4, DR15, or DR53 molecules, indicating that the peptide functions as a promiscuous T-cell epitope. The peptide-reactive T cells responded to autologous dendritic cells loaded with EGFR-expressing tumour cell lysates, indicating that these epitopes are naturally processed. In addition, the CD4 T cells were capable of directly recognising and killing HNSCC cells expressing EGFR and the appropriate HLA class II molecule. T cells reactive with the EGFR875-889 epitope could be detected in the blood of HNSCC patients. EGFR875-889-reactive CD4 T cells were also able to recognise several peptide analogues derived from homologous regions of EGFR family members, HER-2, HER-3 and c-MET. Finally, we examined the effects of EGFR tyrosine kinase inhibition or EGFR-blocking antibodies on CD4 T-cell tumour reactivity. Treatment of tumour cells with the EGFR inhibitors enhanced tumour recognition by EGFR875-889-reactive T cells presumably due to the upregulation of HLA-DR expression in the HNSCC cells. CONCLUSION: We identified novel CD4 T-cell EGFR epitopes and amongst these, EGFR875-889 functions as a promiscuous helper T-cell epitope that can elicit effective antitumour T-cell responses against tumours expressing HER family members and c-MET. These observations should facilitate the translation of T-cell-based immunotherapy into the clinic for the treatment of HNSCC and provide a rational basis for EGFR inhibition, immune-targeted combination therapy.

Biological clock dysfunction exacerbates contact hypersensitivity in mice.

BACKGROUND: Immediate-type skin allergic reactions, such as passive cutaneous anaphylactic reaction, are associated with circadian rhythm, but the role of circadian mechanisms on delayed-type skin allergic reactions, such as contact hypersensitivity (CHS), remains uncertain. In mice, CHS, a T-cell-mediated immune response, is a classic model of human allergic contact dermatitis. OBJECTIVES: We investigated whether biological clock dysfunction affects CHS pathogenesis in CLOCK mutant mice compared with wild-type (WT) mice. METHODS: Mice were treated with 2,4,6-trinitro-1-chlorobenzene (TNCB) on the abdominal skin on day 0 (sensitization) and then treated with TNCB on the ears on day 5 (challenge). RESULTS: We found that biological clock dysfunction resulted in severe inflammation. Ear swelling, serum immunoglobulin E level and mast cell number were significantly increased in CLOCK mutant mice compared with WT mice. These results provide evidence that CLOCK mutation promotes the T-helper type 2 immune response and exacerbates CHS. Corticosterone has a protective effect on CHS. The serum corticosterone level lost rhythmicity and showed a decreased daily level in CLOCK mutant mice compared with WT mice, supporting the exacerbating effect of CLOCK mutation on CHS. Adrenalectomy markedly worsened TNCB-induced CHS in WT mice but not in CLOCK mutant mice. In addition, dramatic dexamethasone-induced protection of CHS was observed in CLOCK mutant mice compared with WT mice. CONCLUSIONS: The present results suggest that circadian rhythm might be an important factor in the regulation of CHS via corticosterone rhythmicity and/or level.

Direct imaging of electron states in open quantum dots.

We use scanning gate microscopy to probe the ballistic motion of electrons within an open GaAs/AlGaAs quantum dot. Conductance maps are recorded by scanning a biased tip over the open quantum dot while a magnetic field is applied. We show that, for specific magnetic fields, the measured conductance images resemble the classical transmitted and backscattered trajectories and their quantum mechanical analogue. In addition, we prove experimentally, with this direct measurement technique, the existence of pointer states. The demonstrated direct imaging technique is essential for the fundamental understanding of wave function scarring and quantum decoherence theory.

Supplementation of the diet of dairy cows with trehalose results in milk with low lipid peroxide and high antioxidant content.

The objective of this study was to investigate the effect of dietary supplementation with the disaccharides trehalose and cellobiose on antioxidant activity in rumen fluid, blood, and milk of dairy cows. Nine Holstein dairy cows housed in a free-stall barn were divided into 3 groups, with each group receiving a different dietary treatment (a control diet, a 1% trehalose-supplemented diet, or a 1% cellobiose-supplemented diet) following a 3x3 Latin square design. Feed intake and milk production increased in cows receiving the trehalose-supplemented diet compared with those receiving the control and cellobiose-supplemented diets. The total protozoa numbers in the rumen fluid of cows fed trehalose- or cellobiose-supplemented diets were greater than those of the control group. The C18:0 and C18:1 fatty acid content was increased in the milk of cows fed the trehalose-supplemented diet compared with that of the control group, and the C18:3n-3 fatty acid content in the milk of cows fed the cellobiose-supplemented diet was less than that of the control group. Plasma biochemical parameters were unchanged among the different treatments. In rumen fluid, 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity and superoxide dismutase activity were increased 2h after feeding in cows receiving the cellobiose-supplemented diet compared with the control group, and the concentration of thiobarbituric acid reactive substances in the rumen fluid of cows fed the cellobiose-supplemented diet was decreased. In contrast, the values of these parameters measured in the milk of cows fed the cellobiose-supplemented diet were no different from those of control cows. Dietary supplementation with trehalose did, however, bring about an improvement of the oxidative status of milk and blood in these animals compared with controls. These results provide the first evidence supporting the use of dietary disaccharides to decrease lipid peroxide levels and increase the antioxidant content of dairy cow milk. The findings suggest that disaccharides, particularly trehalose, might be useful as supplements for reducing oxidative stress and improving the quality of milk for human consumption, as well as possibly impairing the processes that give rise to lipid oxidation odor in dairy cow milk.

Serum and monoclonal immunoglobulin E antibodies from NC/Nga mice with severe atopic-like dermatitis recognize an auto-antigen, histone H3.

BACKGROUND: NC/Nga mice are known to show a spontaneous outbreak of atopic-like dermatitis accompanied by a marked elevation in serum IgE levels when reared in a conventional environment. The specific effects of such a strong serum IgE response on the development of the dermatitis and specific antigens recognized by the IgE antibodies are still uncertain. OBJECTIVE AND METHODS: To characterize the IgE of NC/Nga mice, we established IgE-secreting hybridoma clones from spleen cells of NC/Nga mice spontaneously developing dermatitis and identified variable-region genes and specific antigens of the IgE monoclonal antibodies (mAbs). Serum polyclonal IgE, as well as IgG1 and IgG2a, specific for the identified antigen were also analysed. RESULTS: Four IgE-producing hybridoma clones were established. Variable-region nucleotide sequences of the IgE mAbs showed that these clones did not necessarily share common germline gene segments (V, D or J) for each variable region, and several somatic mutations had occurred in the V gene segments. Through antigen screening, histone H3 was identified to be an auto-antigen recognized by three of the four IgE mAbs. Serum IgE as well as IgG1 specific for histone H3 were almost undetectable in 6-week-old mice, but rapidly increased by 10-12 weeks of age. This age-dependent increase in the serum anti-histone H3 IgE was roughly in parallel with the onset of dermatitis, and slightly preceding total IgE elevation. The serum-specific IgE level correlated well with a dermatitis-severity score of each mouse at 12-16 weeks of age, and weakly with the severity of ear erosion of each mouse over 28 weeks of age. Furthermore, immunologically detectable histone-H3 antigens were observed in skin tissue sections from the dermatitis sites. CONCLUSION: In NC/Nga mice, anti-histone H3 auto-antibodies may contribute, at least in part, to the considerably elevated serum IgE and might play some roles in the development and exacerbation of dermatitis.

Mediation of cardioprotection by transforming growth factor-beta.

Myocardial ischemia causes heart injury that is characterized by an increase in circulating tumor necrosis factor (TNF), the local production of superoxide anions, the loss of coronary vasodilation (relaxation) in response to agents that release endothelial cell relaxation factor, and cardiac tissue damage. Ischemic injury can be mimicked by TNF. When given before or immediately after ischemic injury, transforming growth factor-beta (TGF-beta) reduced the amount of superoxide anions in the coronary circulation, maintained endothelial-dependent coronary relaxation, and reduced injury mediated by exogenous TNF. Thus, TGF-beta prevented severe cardiac injury, perhaps by alleviating damage mediated by increases in circulating TNF.

DUSP22/LMW-DSP2 regulates estrogen receptor-alpha-mediated signaling through dephosphorylation of Ser-118.

In the previous study, we demonstrated the involvement of dual specificity phosphatase 22 (DUSP22/LMW-DSP2) in regulating the leukemia inhibitory factor/interleukin-6/signal transducer and activator of transcription 3-mediated signaling pathway. In this study, we show beta-estradiol (E2)-induced DUSP22 mRNA expression in estrogen receptor alpha (ERalpha)-positive breast cancer cells, whereas E2-induced phosphorylation and activation of ERalpha was suppressed by overexpression of DUSP22 but not catalytically inactive mutants. Furthermore, small-interfering RNA-mediated reduction of DUSP22 expression enhanced ERalpha-mediated transcription and endogenous gene expression. In fact, DUSP22 associated with ERalpha in vivo and both endogenous proteins interacted in ERalpha-positive breast cancer T47D cells. These results strongly suggest that DUSP22 acts as a negative regulator of the ERalpha-mediated signaling pathway.

A xylem sap retrieval pathway in rice leaf blades: evidence of a role for endocytosis?

The structure and transport properties of pit membranes at the interface between the metaxylem and xylem parenchyma cells and the possible role of these pit membranes in solute transfer to the phloem were investigated. Electron microscopy revealed a fibrillar, almost tubular matrix within the pit membrane structure between the xylem vessels and xylem parenchyma of leaf blade bundles in rice (Oryza sativa). These pits are involved primarily with regulating water flux to the surrounding xylem parenchyma cells. Vascular parenchyma cells contain large mitochondrial populations, numerous dictyosomes, endomembrane complexes, and vesicles in close proximity to the pit membrane. Taken collectively, this suggests that endocytosis may occur at this interface. A weak solution of 5,6-carboxyfluorescein diacetate (5,6-CFDA) was applied to cut ends of leaves and, after a minimum of 30 min, the distribution of the fluorescent cleavage product, 5,6-carboxyfluorescein (5,6-CF), was observed using confocal microscopy. Cleavage of 5,6-CFDA occurred within the xylem parenchyma cells, and the non-polar 5,6-CF was then symplasmically transported to other parenchyma elements and ultimately, via numerous pore plasmodesmata, to adjacent thick-walled sieve tubes. Application of Lucifer Yellow, and, separately, Texas Red-labelled dextran (10 kDa) to the transpiration stream, confirmed that these membrane-impermeant probes could only have been offloaded from the xylem via the xylem vessel-xylem parenchyma pit membranes, suggesting endocytotic transmembrane transfer of these membrane-impermeant fluorophores. Accumulation within the thick-walled sieve tubes, but not in thin-walled sieve tubes, confirms the presence of a symplasmic phloem loading pathway, via pore plasmodesmata between xylem parenchyma and thick-walled sieve tubes, but not thin-walled sieve tubes.

Randomized controlled trial for an effect of green tea-extract powder supplementation on glucose abnormalities.

OBJECTIVE: We examined whether green tea-extract powder supplementation improves glucose abnormality. METHODS: The study was conducted for volunteers who resided in eastern communities of Shizuoka Prefecture and who had fasting blood glucose levels of >or=6.1 mmol/l or nonfasting blood glucose levels of >or=7.8 mmol/l in a recent health check-up. Sixty subjects aged 32-73 years (49 males and 11 females) participated in the trial. The Early intervention group consumed a packet of green tea-extract powder containing 544 mg polyphenols (456 mg catechins) daily for the first 2 months and then entered the 2-month nonintervention period. The Later intervention group was observed for the first 2 months and then consumed green tea-extract powder as described above for the subsequent 2 months. Using the two-period crossover design, we analyzed the changes in fasting hemoglobin A1c level and other biomarkers in blood samples collected at baseline, 2 months and 4 months. RESULTS: A significant reduction in hemoglobin A1c level and a borderline significant reduction in diastolic blood pressure were associated with the intervention. The intervention caused no significant changes in weight, body mass index, body fat, systolic blood pressure, fasting serum glucose level, homeostasis model assessment index, serum lipid level or hypersensitive C-reactive protein. CONCLUSION: Daily supplementary intake of green tea-extract powder lowered the hemoglobin A1c level in individuals with borderline diabetes.

Routine Referral by Urologists Increase Opportunities for Corneal Donation.

BACKGROUND: The levels of corneal donation are insufficient to meet the demand for corneal transplantation in Japan. To overcome this problem, we started to routinely mention the possibility of corneal donation to the families of patients who died in our hospital's Urology Department in February 2008. In this study, we evaluated the effectiveness of this approach. METHODS: We retrospectively reviewed the medical records of the patients who died in the Department of Urology, St. Marianna University School of Medicine Hospital, and analyzed the patients' characteristics and information about corneal donation. RESULTS: In total, 211 patients died in our department between February 2008 and March 2017, and 155 patients were medically suitable corneal donors. We mentioned the possibility of corneal donation to 129 (83.2%) families, and 29 (18.7%) families agreed. Three families subsequently withdrew their consent. Finally, 26 (16.8%) of the families that were approached about corneal donation by urologists agreed to donate their relatives' corneas. Another 2 families voluntarily offered to donate their relatives' corneas. Thus, 28 (18.1%) of 155 medically suitable donors donated their corneas for transplantation. Twenty-six (92.8%) donors were 60 years or older and all donors were affected with malignant genitourinary tumors. Fifty-four (96.4%) corneas were successfully transplanted into recipients. CONCLUSIONS: Even elderly patients who die of solid carcinoma can be an important source of corneal donors. In this study, we showed that routine referral by urologists increased corneal donation. If this approach were adopted by other departments, it might further increase the number of corneal donations.

Regulation of STAT3-mediated signaling by LMW-DSP2.

Signal transducer and activator of transcription 3 (STAT3), which mediates biological actions in many physiological processes, is activated by cytokines and growth factors, and has been reported to be constitutively activated in numerous cancer cells. In this study, we examined whether low molecular weight-dual specificity phosphatase two (LMW-DSP2) is involved in the regulation of the interleukin 6 (IL-6)/leukemia inhibitory factor (LIF)/STAT3-mediated signaling pathway. IL-6/LIF-induced LMW-DSP2 expression in murine testicular or hepatoma cell lines, while LMW-DSP2 overexpression in 293T cells suppressed IL-6-induced phosphorylation and activation of STAT3. Furthermore, LMW-DSP2 suppressed the expression of IL-6-induced endogenous genes. In contrast, small-interfering RNA-mediated reduction of LMW-DSP2 expression enhanced IL-6-induced STAT3-dependent transcription. In fact, LMW-DSP2 interacted with STAT3 in vivo and endogenous LMW-DSP2 bound to STAT3 in murine testicular GC-1 cells. These results strongly suggest that LMW-DSP2 acts as a negative regulator of the IL-6/LIF/STAT3-mediated signaling pathway.

Significance of cross-linking of alpha 2-plasmin inhibitor to fibrin in inhibition of fibrinolysis and in hemostasis.

When blood is clotted, alpha(2)-plasmin inhibitor (alpha(2)PI) is cross-linked to fibrin by activated fibrin-stabilizing factor (activated coagulation Factor XIII, plasma transglutaminase). The amount of cross-linked alpha(2)-PI is proportional to the amount of alpha(2)PI present at the time of clotting. Plasma from a patient with congenital deficiency of alpha(2)PI was supplemented with various amounts of purified alpha(2)PI. Clots were prepared from these plasmas and were suspended in plasma containing a normal concentration of alpha(2)PI, and spontaneous clot lysis was observed. When the clot was formed in the presence of calcium ions and thereby allowing cross-linking to occur, the rate and extent of fibrinolysis were found to be inversely proportional to the concentrations of alpha(2)PI present in the clot at the time of clotting. When the clot was formed in the absence of calcium ions so that no cross-linking occurred, the clot underwent fibrinolysis at similar rates, regardless of the concentrations of alpha(2)PI in the clot. When the clot formed in the presence of calcium ions was squeezed and washed to remove unbound proteins before being suspended in plasma, the extent of fibrinolysis was also inversely proportional to the amount of alpha(2)PI cross-linked to fibrin. Similar results were obtained when the clot was suspended in buffered saline instead of plasma. These observations suggest that spontaneous fibrinolysis is mainly carried out by plasminogen/plasminogen activator bound to fibrin, and this fibrinolysis caused by fibrin-associated activation of plasminogen was mainly inhibited by alpha(2)PI cross-linked to fibrin. To further support this concept, alpha(2)PI treated with activated fibrin-stabilizing factor and that had lost most of its cross-linking capacity was used in similar experiments. This modified alpha(2)PI had the same inhibitory activity on plasmin as the native inhibitor, but gave significantly less inhibition of fibrinolysis in every experiment, particularly when the clot was compacted by platelet-mediated clot retraction or by squeezing. Thus, it was concluded that alpha(2)PI cross-linked to fibrin plays a significant role in inhibition of physiologically occurring fibrinolysis. It is further suggested that the absence of cross-linked alpha(2)PI contributes to accelerated fibrinolysis and hemorrhagic tendency in patients with congenital deficiency of fibrin-stabilizing factor.