Histopathological and immunophenotypic features of ipilimumab-associated colitis compared to ulcerative colitis.

BACKGROUND: Use of the immune checkpoint inhibitor ipilimumab is sometimes complicated by ipilimumab-associated colitis (Ipi-AC), an immune-mediated colitis that mimics inflammatory bowel disease. OBJECTIVE: We sought to characterize the histopathologic and immunophenotypic features of Ipi-AC and to directly compare these features to ulcerative colitis (UC). METHODS: This is a retrospective cohort study of 22 patients with Ipi-AC, 12 patients with treatment-naïve UC and five controls with diarrhoea but normal endoscopic findings. Immunohistopathologic features were described, and quantitative immunohistochemistry (IHC) was performed for CD4, CD8, CD20, CD138 and FOXP3. RESULTS: Endoscopic findings in both the Ipi-AC and UC groups included ulcerated, oedematous and erythematous mucosa. Involvement of the GI tract was more diffuse in Ipi-AC. As compared to UC, a smaller proportion of Ipi-AC biopsies had basal plasmacytosis (14% for Ipi-AC vs. 92% for UC, P < 0.0001) and crypt distortion (23% for Ipi-AC vs. 75% for UC, P = 0.003), whereas Ipi-AC biopsies had more apoptotic bodies in the left colon (17.6 ± 15.3 for Ipi-AC vs. 8.2 ± 4.2 for UC, P = 0.011). Cryptitis, ulcerations and crypt abscesses were common in both groups. Biopsy specimens from Ipi-AC had a lower density of CD20-positive lymphocytes than UC (275.8 ± 253.3 cells mm-2 for Ipi-AC vs. 1173.3 ± 1158.2 cells mm-2 for UC, P = 0.022) but had a similar density of CD4, CD8, CD138 and FOXP3-positive cells. CONCLUSIONS: Ipi-AC is a distinct pathologic entity with notable clinical and histopathological differences compared to UC. These findings provide insights into the pathophysiology of immune-related adverse events (iAEs) from ipilimumab therapy.

Recent advances on lactose intolerance: Tolerance thresholds and currently available answers.

The genetically programmed reduction in lactase activity during adulthood affects 70% of the world adult population and can cause severe digestive disorders, which are the sign of lactose intolerance. Lactose intolerance symptoms vary depending on the residual lactase activity, the small bowel transit time, and especially the amount of ingested lactose. To formulate dairy products suitable for the vast majority of lactose intolerants, it is essential to define lactose intolerance threshold. A recent meta-analysis permitted to show that almost all lactose intolerants tolerate 12 g of lactose in one intake and approximately 18 g of lactose spread over the day. The prevalence and severity of lactose intolerance are probably overestimated by the general public. This misconception usually leads to an unnecessary reduction of dairy foodstuff consumption. Nevertheless, dairy products are essential for health mainly due to their calcium content and the positive influence of probiotic bacteria. The formulation of dairy products suitable for most intolerant and suspicious subjects seems necessary. The use of exogenous enzyme preparations, as well as the consumption of lactose-free products or products rich in probiotic bacteria are proposed as symptom-reducing strategies.

ZnO nanowires-C microfiber hybrid nanosensor for liquefied petroleum gas detection.

Zinc oxide nanowires are integrated onto carbon microfibers using a two-step approach which includes electrochemical deposition of zinc and its thermal oxidation. Such nano-on-micro hybrid architecture is then used as resistive gas sensor. Some properties like mechanical flexibility, low cost and large-area fabrication make this design appealing for different applications. The huge surface-to-volume ratio of such structure comes from being structured at both microscale and nanoscale (ZnO nanowires and C microfiber) and leads to a strong and rapid response/recovery times when it is used as a gas sensor. The fabrication process of the ZnO-microC device is very simple and doesn't involve any expensive lithographic step. The sensors show excellent liquefied petroleum gas sensing properties, with very fast response on gas exposure (about 3 s) and very good reversibility (less than 2%). In addition, the carbon microfiber substrate allows the use of the ZnO-microC sensor also in applications where flexibility is required (for example integrated in fabric).

The upper extremity regional anaesthesia trifecta: three upper extremity nerve blocks for awake upper-limb surgery in a patient with a history of contralateral pneumonectomy.

While regional anaesthesia plays a pivotal role in the perioperative management of patients undergoing upper extremity surgery, its utility can be limited by the risk of hemi-diaphragmatic paresis. Furthermore, each approach to blocking the brachial plexus has associated limitations that may result in incomplete upper extremity anaesthesia. We describe the combination of three upper extremity nerve blocks to achieve surgical anaesthesia of the whole arm for a patient who had previously undergone a contralateral pneumonectomy. On this occasion, she required upper arm lipectomy and arteriovenous fistula formation. Adequate blockade was achieved with no significant perioperative complications. This case demonstrates the potential of this approach for patients with respiratory compromise undergoing upper limb procedures.

Prognostic factors for surgical outcomes among patients with multilevel cervical spondylotic myelopathy.

OBJECTIVE: Many clinical and imaging characteristics can influence the prognosis of multilevel cervical spondylotic myelopathy (M-CSM). This study investigated the factors that influence surgical outcomes among patients with M-CSM. PATIENTS AND METHODS: This prospective study included 30 patients who underwent surgical treatment for M-CSM from June 2019 to June 2021. RESULTS: The average age was 62.29 years, and the average follow-up time was 13.13 months. Preoperative, postoperative, and follow-up Modified Japanese Orthopaedic Association (mJOA) scores were 10.17, 13.53, and 16.17, respectively. The average postoperative and follow-up recovery rates were 45.46% and 76.69%, respectively. Patients older than 60 years (p = 0.04), male patients (p = 0.023), and smokers (p = 0.027) had lower preoperative mJOA scores than other groups. Patients with symptoms duration longer than 6 months had lower recovery rates (p = 0.021) than those with shorter symptom duration. Patients with intramedullary hyperintensity in ≤ 2 vertebra (p = 0.041) or anterior surgery (p = 0.022) had better postoperative recovery rates than their counterparts. A shorter period of hyperintensity in the intramedullary region on sagittal T2-weighted magnetic resonance imaging (T2W MRI) was significantly associated with faster discharge (p = 0.044). Patients with type 3 (discrete focal) hyperintensity in the intramedullary region on axial T2W MRI had a 6.75-fold increase in experiencing less than 50% postoperative recovery compared with other groups (odds ratio: 6.75, 95% confidence interval: 2.73-16.67). CONCLUSIONS: Good prognostic factors for a shorter recovery included hyperintensity in the intramedullary region for ≤ 2 levels, shorter period of hyperintensity in the intramedullary region on sagittal T2W MRI, and an anterior surgical approach. A duration of symptoms longer than 6 months and discrete hyperintensity in the intramedullary region on axial T2W MRI were poor prognostic indicators associated with a longer recovery period.

Examining the link between thoracic rotation and scapular dyskinesis and shoulder pain amongst college swimmers.

OBJECTIVES: In National Collegiate Athletic Association Division I swimmers, we examined the differences in thoracic spine rotation in swimmers with and without scapular dyskinesis and the relationship between thoracic spine rotation and shoulder pain/dysfunction according to the Kerlan-Jobe Orthopaedic Clinic (KJOC) score. DESIGN: Cross-sectional. SETTING: Laboratory-based. PARTICIPANTS: 34 NCAA Division I swimmers (13 males, 21 females). MAIN OUTCOME MEASURES: Self-reported upper extremity function and pain assessed with the KJOC questionnaire, thoracic spine range of motion, presence of scapular dyskinesis. RESULTS: Dyskinesis was present in 15 of 34 (44%) subjects. Thoracic rotation averaged 136.7° and KJOC averaged 87.7 with no differences between swimmers with or without dyskinesis. We observed no correlation between KJOC-identified shoulder pain/dysfunction and thoracic rotation. CONCLUSIONS: In our cohort of NCAA Division 1 swimmers, no differences were found between swimmers with or without scapular dyskinesis and extent of thoracic rotation. We found no correlation between thoracic rotation and the amount of self-reported pain and dysfunction experienced in the upper extremity. The presence of scapular dyskinesis in nearly half of our subjects indicates that swimmers need to be assessed for this abnormality. If observed, rehabilitation should address the dyskinesis and improve thoracic rotation in an attempt to alleviate further upper extremity pain and dysfunction.

The hypercoagulable state in sleep apnea is related to comorbid hypertension.

OBJECTIVE: Obstructive sleep apnea (OSA) is associated with increased prevalence of atherosclerotic disease. A hypercoagulable state thought to underly atherosclerosis has been described in both OSA and systemic hypertension. We wondered about the respective contribution of apnea and hypertension to a hypercoagulable state. DESIGN: Eighty-seven subjects with symptoms suggestive of OSA, mean age 47 years (range 32-64 years), underwent polysomnography and blood pressure (BP) screening. OSA was diagnosed when respiratory disturbance index (RDI) > or = 15. Subjects having systolic BP (SBP) > 140 mmHg and/or diastolic BP (DBP) > 90 mmHg were classified as having hypertension. Three hypercoagulability markers were measured: thrombin/antithrombin III complex (TAT), fibrin D-dimer (DD), and von Willebrand factor antigen (vWF:ag). RESULTS: Analysis of variance and multiple linear regression were performed on the following four subject groups: (1) normotensive non-apneics (n = 19), (2) normotensive apneics (n = 38), (3) hypertensive non-apneics (n = 11), and (4) hypertensive apneics (n = 19). OSA (groups 2 and 4) had no significant main effect on hemostasis. Hypertensives (groups 3 and 4) had higher plasma levels of TAT (median/inter-quartile range, 148/59-188 versus 77/53-108 pmol/l; P = 0.009) and of DD (376/265-721 versus 303/190-490 ng/ml; P = 0.040) than normotensives (groups 1 and 2). Across all subjects, SBP was the only significant predictor of TAT (P = 0.001) and of DD (P = 0.004), whereas DBP was the only significant predictor of vWF:ag (P = 0.029). These findings persisted even after controlling for gender, age, body mass index, RDI, mean SaO2, and hematocrit. CONCLUSION: Hypercoagulability in OSA is mediated by comorbid hypertension and might account for high cardiovascular morbidity in OSA in general.

Studies of the mechanism for enhanced cell surface factor VIIa/tissue factor activation of factor X on fibroblast monolayers after their exposure to N-ethylmaleimide.

Fibroblast monolayers constitutively expressing surface membrane tissue factor (TF) were treated with 0.1 mM N-ethylmaleimide (NEM) for 1 min to inhibit aminophospholipid translocase activity without inducing general cell damage. This resulted in increased anionic phospholipid in the outer leaflet of the cell surface membrane as measured by the binding of 125I-annexin V and by the ability of the monolayers to support the generation of prothrombinase. Specific binding of 125I-rVIIa to TF on NEM-treated monolayers was increased 3- to 4-fold over control monolayers after only brief exposure to 125I-rVIIa, but this difference progressively diminished with longer exposure times. A brief exposure of NEM-treated monolayers to rVIIa led to a maximum 3- to 4-fold enhancement of VIIa/TF catalytic activity towards factor X over control monolayers, but, in contrast to the binding studies, this 3- to 4-fold difference persisted despite increasing time of exposure to rVIIa. Adding prothrombin fragment 1 failed to diminish the enhanced VIIa/TF activation of factor X of NEM-treated monolayers. Moreover, adding annexin V, which was shown to abolish the ability of NEM to enhance factor X binding to the fibroblast monolayers, also failed to diminish the enhanced VIIa/TF activation of factor X. These data provide new evidence for a possible mechanism by which availability of anionic phospholipid in the outer layer of the cell membrane limits formation of functional VIIa/TF complexes on cell surfaces.

Reliability of a modified tissue factor-dependent factor V assay for activated protein C resistant factor Va using a calcium-containing thromboplastin.

The original tissue factor-dependent factor V assay for activated protein C resistant factor Va (Blood 1995; 85: 1704-1711) has been modified to use a calcium containing thromboplastin and to express results as an observed to expected ratio (Obs/Exp.). The latter permits establishing a normal range independent of variations due to differences in reagents. Comparing Obs/Exp ratios with DNA analysis in 72 persons revealed that an Obs/Exp ratio of 0.6 distinguished without overlap normals from heterozygotes for FV R506Q. Three homozygotes had a ratio of < 0.1. Application of this Obs/Exp cut-off ratio of 0.6 to a total of 226 plasma samples tested to date discriminated without overlap between normals and heterozygotes. We conclude that this assay-readily adaptable to any dedicated coagulation laboratory and capable of yielding reliable results in all clinical circumstances in which testing is indicated-can distinguish between normals and heterozygotes for the FV R506Q mutation without the need for confirmatory DNA analysis.

A novel clotting assay for quantitation of plasma prothrombin (factor II) using Echis multisquamatus venom.

Measuring plasma prothrombin activity seems useful for evaluating thrombotic risk and managing oral anticoagulant therapy as an adjunct to the international normalized ratio. Therefore, we designed a new plasma prothrombin assay based on the ability of Echis multisquamatus venom to activate prothrombin with only calcium as a cofactor. In this assay, 1 part of undiluted citrated plasma is added to 5 parts of a venom reagent and the clotting time is measured. The assay's advantages are that dilution of the test plasma is required only when prothrombin activity exceeds 100%, a single standard curve can be used over months for a given batch of stock reagent, and barium-adsorbed plasma is used for dilution of test plasma and construction of the standard curve, thus eliminating the need for prothrombin-deficient plasma. However, one should be aware of the following: (1) test samples must contain at least 200 mg/dL fibrinogen; and (2) when prothrombin concentrations were below 50%, the venom-based assay often gave values up to 10% higher than the thromboplastin-based assay. Values obtained in 262 plasma samples tested with the venom-based assay and with a thromboplastin-based prothrombin assay correlated well (r2 = 0.93).

Decrease in the plasma von Willebrand factor concentration following glucose ingestion: the role of insulin sensitivity.

Elevated plasma von Willebrand factor (vWF) concentration is thought to be associated with increased prevalence of cardiovascular events in the insulin resistance syndrome. We examined the effects of oral glucose challenge and accompanying metabolic and hemodynamic changes on vWF levels with respect to insulin sensitivity. Forty normotensive and hypertensive subjects (mean age +/- SD, 40 +/- 5 years) underwent a standard oral glucose tolerance test (OGTT). Plasma vWF antigen, glucose, insulin, catecholamines, and hemodynamics were measured at rest, and at 30, 60, 90, and 120 minutes after glucose intake. Insulin sensitivity was determined by the insulin sensitivity index (ISI(0,120)). Resting plasma vWF concentration was associated with screening systolic blood pressure (BP) (r =.43, P =.005). There were time effects for all variables of interest. While vWF antigen (P =.044), epinephrine (P =.003), and diastolic BP (P =.001) decreased after glucose challenge, norepinephrine (P =.009), systolic BP (P =.022), and heart rate (P <.001) increased. Decline in vWF (area under the curve) was associated with decrease in epinephrine (r =.46, P =.004) and with screening systolic BP (r =.45, P =.004). However, neither resting plasma vWF levels nor vWF decrease following glucose ingestion were significantly associated with the ISI(0,120.) The plasma vWF concentration decreases following glucose ingestion. While mechanisms underlying this phenomenon may relate to sympathetic nervous system function, they seem not related to insulin sensitivity. Endothelial dysfunction such as caused by hypertension rather than metabolic dysregulation per se may underlie the elevated plasma vWF concentration found with insulin resistance.

A Protac-based screening test for activated protein C-resistant factor Va and other defects of the protein C anticoagulant pathway.

We have standardized a simple screening test for abnormalities of the protein C anticoagulant system. The test is basically a modified prothrombin time in which one aliquot of a test plasma is incubated for 3 min at 37 degrees C with Protac and another is incubated with buffer. During the incubation the Protac activates both protein C and factor V. The plasmas are then clotted with thromboplastin plus Ca2+, and the clotting time difference reflects the ability of the activated protein C (APC) to inactivate factor Va. With the use of Thromboplastin C Plus as the activator, clotting time differences found in 31 normal subjects (10.4 +/- 3.5 s, mean +/- 2SD) were distinct from clotting time differences found in 57 of 58 subjects with established APC-resistant factor Va (3.6 +/- 3.0 s). In addition, the Protac-based test detected six of seven patients with isolated protein C deficiency and 20 of 28 patients with isolated protein S deficiency. Because of the reported high prevalence of heterozygous APC-resistant factor Va in Caucasian populations, it should be particularly useful in determining whether this genetic risk is present in individuals who have experienced or are at increased environmental risk of venous thrombosis.

Severe alveolar proteinosis following chemotherapy for acute myeloid leukemia in a lung allograft recipient.

A 64-year-old man was diagnosed with acute myeloid leukemia (AML) 5 years following single lung transplantation performed for severe pulmonary hypertension from scleroderma. Chemotherapy for treatment of AML with fludarabine, cytosine arabinoside, G-CSF (FLAG) regimen was initiated. Despite intensive antibiotic treatment for a presumptive diagnosis of bacterial pneumonia, the patient developed acute respiratory failure and died before a complete cycle of chemotherapy could be administered. At autopsy, both native and allograft lungs showed widespread alveolar proteinosis that was determined as the main cause of acute respiratory failure. Alveolar proteinosis, a potentially treatable disease, should be considered in the radiologic differential diagnosis of diffuse lung disease in this clinical setting.

Quantitative effects of nefiracetam on spatial learning of rats after cerebral embolism.

UNLABELLED: Recent studies have shown that nefiracetam ameliorates cognitive dysfunction because of ischemia when behavioral testing occurs during treatment. We sought to determine if there was a persistent effect after treatment, by testing spatial learning of embolized rats after nefiracetam therapy. METHODS: Male Sprague Dawley rats (250 to 300 g) were divided into 3 categories. The control group (n = 5) underwent no surgery or cerebral embolism. The vehicle group (n = 12) was anesthetized with halothane, underwent surgery, injected with intracarotid microspheres, and given orally 5 mL/kg of the vehicle (0.5% aqueous sodium carboxymethyl cellulose) for 21 days. The nefiracetam group (n = 12) was embolized and treated orally with 30 mg/kg nefiracetam (6 mg/mL in vehicle) for 21 days. Outcome was determined with visual spatial learning after the end of treatment. RESULTS: Embolization caused a significant impairment in visual spatial learning, which nefiracetam completely ameliorated (group main effect, F(2,444) = 6.4, P = .002). Mean latency to the escape was 35 +/- 6 seconds for the vehicle group versus 18 +/- 4 seconds for the nefiracetam group, after 4 days of testing. This effect persisted after a further interval of 10 days (retention test). A reversal test (to assess working memory for new information) yielded mean latencies of 26 +/- 6 seconds for the control group, 49 +/- 5 seconds for vehicle, and 25 +/- 4 seconds for nefiracetam (group main effect, F(2,109) = 8.0, P = .0005, Newman-Keuls, P < .05), showing that both the control and nefiracetam groups were different from the vehicle group. CONCLUSION: Nefiracetam therapy improves the learning behavior of embolized rats. The results are not caused by an activating effect of the drug because the animals are tested after the treatment period is over and because the beneficial effect is seen using the delayed retention test. Finally, working memory is markedly preserved by nefiracetam, an effect observed several weeks after treatment.

Purification of labeled cyanogen bromide peptides of the alpha polypeptide from sodium ion and potassium ion activated adenosinetriphosphatase modified with N-[3H]ethylmaleimide.

Sodium ion and potassium ion activated adenosinetriphosphatase, isolated from canine kidney, was reacted with N-[3H]ethylmaleimide while it was poised in three different conformations, ostensibly E2-P, E2, and E1, respectively. These assignments were made from a consideration of the particular concentrations of ligands in the respective alkylation mixtures. After a 30-min reaction, the remaining enzymatic activity was found to vary among these three different samples from 90 to 30% of that of unalkylated controls. In all cases, the alpha polypeptide was purified and subjected to digestion with cyanogen bromide, and in each digest the same two distinct radioactive peptides were identified and purified by gel filtration on a column of Sephadex LH-60. The incorporation of N-[3H]ethylmaleimide into one of these two peptides correlated closely with enzymatic inactivation, while the incorporation into the other was most extensive when the portion of the active site to which ATP binds was unoccupied. Alkylation of the residue within the latter peptide, however, does not result in inactivation of the enzyme. Both peptides were further purified by high-pressure liquid chromatography, and their amino-terminal sequences were determined by manual dansyl Edman or solid-phase techniques. The peptide containing the sulfhydryl protected by ATP has, as its amino terminus, the lysine that reacts exclusively with fluoresceinyl 5'-isothiocyanate [Farley, R. A., Tran, C. M., Carilli, C. T., Hawke, D., & Shively, J. E. (1984) J. Biol. Chem. 259, 9532-9535].

Relations between factor VIIa binding and expression of factor VIIa/tissue factor catalytic activity on cell surfaces.

The kinetics of the binding of rVIIa to cell surface tissue factor (TF) and the resultant expression of VIIa/TF activity were studied. Binding of 125I-rVIIa (10 nM) to cell surface TF required 30-60 min for saturation, whereas VIIa/TF activity was fully expressed toward factor X (F X) on intact monolayers after only 1 min of incubation. At the time only 10-20% of the total VIIa TF complexes present at saturation had formed. Freeze-thawing the monolayers before assay increased VIIa/TF activity up to 30-fold, and the time course of its expression was similar to that of TF-specific binding of VIIa to the monolayers. Equilibrium binding revealed a single high affinity binding class of TF sites on intact monolayers for rVIIa with a Kd of 1.6 nM. Experiments with active-site inhibited rVIIa yielded evidence for two populations of VIIa. TF complexes on intact monolayers: (1) a minor population (less than 20%) that formed within 1 min of incubation and accounted for all VIIa/TF activity toward F X present on the intact monolayers, and (2) a major population that was inactive toward F X on intact monolayers but which was fully active after the monolayers were lysed. Tissue factor pathway inhibitor (TFPI).F Xa complexes inhibited the VIIa/TF activity of the first population, i.e. of the complexes active on intact monolayers, half maximally at a concentration of 0.2 nM TFPI. TFPI/Xa also bound to the second population of VIIa.TF complexes on intact monolayers and inhibited their expression of VIIa/TF activity following cell lysis with a half-maximal inhibitory concentration of 2.0 nM. The potential physiologic implications of these findings are discussed.

Non-sense and missense mutations in the structural genes of complement component C1q A and C chains are linked with two different types of complete selective C1q deficiencies.

To shed light on the molecular basis of two different types of complete C1q deficiency, we performed extensive Southern blot analysis and sequenced all exons of the genes coding for the A, B, and C chains of C1q on two groups of deficient patients. In one family with three cases of complete C1q deficiency we found a point mutation in the codon for glutamine (CAG) at position 186 of the A chain that led to a termination codon (TAG). No gene products of any of the three genes were found in the patients' sera, indicating that full length polypeptides of the A, B, and C chains are required to form and secrete functional C1q. A second point mutation was found in a patient with a complete functional C1q defect. The abnormal C1q molecule had been shown to have a low m.w. of approximately 150,000 and a sedimentation coefficient of below 7S. The mutation occurred in the codon for glycine in position 6 of the C chain where a single base exchange (G-->A transition) has led to an arginine residue. In the parents and son of patient G we could demonstrate the heterozygous state of the mutation by the occurrence of both bases in question, G and A. The interruption of the collagen-like triplet motif Gly-X-Y and, even more likely, the introduction of a large positively charged side chain at the N-terminus of the polypeptide may inhibit the assembly of three structural subunits consisting of two A-B dimers and one C-C dimer to form the 11S C1q macromolecule.

Correction of excessive anticoagulation with low-dose oral vitamin K1.

BACKGROUND: Despite earlier acceptance of oral vitamin K1 (phytonadione) for the treatment of excessive anticoagulation, some recent guidelines do not recommend its use. OBJECTIVE: To reevaluate the efficacy of oral vitamin K1 in correcting excessive anticoagulation. DESIGN: Case series. SETTING: Anticoagulation clinics at two university medical centers. PATIENTS: 81 outpatients who had an international normalized ratio (INR) greater than 5.0 but did not have significant bleeding. INTERVENTIONS: Withholding 1 or 2 doses of warfarin, administering 2.5 mg of oral vitamin K1, measuring the INR after 24 to 48 hours, and adjusting the warfarin dose. MEASUREMENTS: INRs were obtained from a portable capillary fingerstick monitor or from an automated photooptical coagulometer. RESULTS: In 68 of 71 patients (96%), oral vitamin K1 lowered the INR from between 5.0 and 10.0 to less than 5.0 without inducing resistance to further anticoagulation. CONCLUSIONS: Withholding 1 or 2 doses of warfarin and administering 2.5 mg of oral vitamin K1 is a reliable, safe, and inexpensive way to rapidly correct excessive anticoagulation (INR > 5.0) in patients who do not have serious bleeding episodes and have an INR of less than 10.0.