A cellulose-based photoacoustic sensor to measure heparin concentration and activity in human blood samples.

Heparin is an indispensable drug in anticoagulation therapy but with a narrow therapeutic window, which dictates regular testing and dose adjustment. However, current monitoring tools have a long turnaround time or are operator intensive. In this work, we describe a cellulose-based photoacoustic sensor for heparin. The sensors have a turnaround time of 6 min for whole blood samples and 3 min for plasma samples regardless of heparin concentration. These sensors have a limit of detection of 0.28 U/ml heparin in human plasma and 0.29 U/ml in whole blood with a linear response (Pearson's r = 0.99) from 0 to 2 U/ml heparin in plasma and blood samples. The relative standard deviation was < 12.5% in plasma and < 17.5% in whole blood. This approach was validated with heparin-spiked whole human blood and had a linear correlation with the activated partial thromboplastin time (aPTT) (r = 0.99). We then studied 16 sets of clinical samples-these had a linear correlation with the activated clotting time (ACT) (Pearson's r = 0.86, P < 0.0001). The photoacoustic signal was also validated against the cumulative heparin dose (Pearson's r = 0.71, P < 0.0001). This approach could have applications in bed-side heparin assays for continuous heparin monitoring.

Flow cytometric detection of altered signaling in myelodysplastic syndrome and cytopenia.

Multiparameter flow cytometric analysis allows for precise evaluation of growth factor stimulated intracellular signaling in distinct immunophenotype defined hematopoetic populations. Our analysis of intracellular phosphoprotein in response to major hematopoietic growth factors or cytokines showed several interesting findings. Although there was no characteristic signaling abnormality that was diagnostic for MDS, MDS cases were often associated with more signaling aberrancies involving more cellular populations. Higher than average response in the CD34(+)CD117(+) progenitor cells to Flt3 ligand and stem cell factor stimulation was frequently associated with high risk features or disease progression in MDS. Although preliminary results hint an adverse prognostic role of dysregulated FLT3 pathway in MDS cases, whether this observation adds independent prognostic value to the existing prognostic system needs to be further explored in future prospective studies.

Acquired and Heritable Thrombophilia in Indian Patients With Pediatric Deep Venous Thrombosis (DVT).

Deep venous thrombosis (DVT) in children is more often associated with underlying pathological conditions than with hereditary thrombophilia. The present study is a retrospective analysis of thrombophilia in 285 pediatric patients with venous thrombosis at different sites. Four common thrombophilia markers, that is protein C, protein S, antithrombin III, and factor V Leiden (FVL) mutation, were analyzed. Thrombosis in hepatic and portal veins was more common in pediatric patients (73%) when compared to other sites (27%). Overall, hereditary thrombophilia accounted for 15.5% of the patients with venous thrombosis. The FVL mutation, which was the major causative factor in Budd-Chiari syndrome and portal vein thrombosis cases in the adult group, was not a major contributing factor in pediatric group, that is, 1.8% of the patients. In conclusion, the risk factors for venous thrombosis vary in different age groups.

Hereditary thrombophilia in cerebral venous thrombosis: a study from India.

A systematic study of thrombophilia markers in a large series of patients with cerebral venous thrombosis (CVT) from India is scarce. The present study was undertaken to know the prevalence of common hereditary thrombophilia in a large series of CVT patients from India. Six hundred and twelve (354 men, 219 women and 39 children) consecutive patients with CVT admitted to various hospitals in Mumbai between 2001 and 2010 were investigated for the common thrombophilia markers, that is, protein C (PC), protein S, antithrombin (AT), and factor V Leiden (FVL) mutation. The main presenting clinical manifestations included papilledema (62%), headache (62%), hemiparesis (48%), seizures (31%), and cranial nerve palsy (7%). All the patients were managed with heparin followed by warfarin during the succeeding 6 months. Superior sagittal sinus thrombosis was the commonest site (74%) followed by cortical venous thrombosis (15%). Associated clinical pathologies were dehydration, sepsis, pregnancy and puerperium, malaria, and tuberculosis; but in the majority of patients, there was no obvious cause. Eighteen percent of the patients had any of the thrombophilia markers studied; PC deficiency was the commonest thrombophilia marker followed by deficiency of protein S, FVL mutation and AT deficiency. The men below 45 years with PC deficiency (P=0.03) and women with protein S deficiency were significantly higher (P=0.04). In conclusion, CVT is not an uncommon cause of neurological deficit as was presented in earlier reports. Pregnancy and puerperium-related CVT was much less common. Thrombophilia markers accounted for approximately one-fifth of the patients. Death due to CVT has shown remarkable reduction (13%) because of early diagnosis and appropriate anticoagulation.

Hereditary protein C deficiency in Indian patients with venous thrombosis.

Approximately, 4-11 % of the patients with idiopathic venous thrombosis (VT) show protein C (PC) deficiency. The molecular pathology of PC deficiency was analyzed in 102 patients; 98 healthy controls were also studied to assess the association of various polymorphisms with reduced PC levels. PROC gene mutations were detected only in 8 (7.8 %) patients with reduced PC levels. PROC promoter region CG polymorphisms showed statistically significant association with reduced PC levels (p < 0.001). PC deficiency in Indian VT patients can, thus, largely be explained by PROC gene promoter CG polymorphisms; only a small fraction of the patients show specific mutations in PROC gene.

Cause of deep venous thrombosis and pulmonary embolism in young patients from India as compared with other ethnic groups.

Venous thromboembolism (VTE), which consists of deep vein thrombosis (DVT) and pulmonary embolism, is a potentially fatal disease. The existing Asian literature has shown a wide variation in the prevalence of VTE, with very limited data from India. In the present study, the risk factors for VTE in Indian patients were compared with Caucasians and Blacks. We used data prospectively collected from total of 1396 Indian patients (716 males, 680 females) enrolled over a decade and compared with White (n = 2002) and Black (n = 395) patients objectively diagnosed with VTE. When compared with females, males had significantly higher episodes of pulmonary embolism and VTE (P = 0.0001). Amongst the known thrombophilia markers, only homocysteine was found to be significantly higher in males as compared with females (P = 0.006). Males had a higher proportion of rheumatic heart disease (RHD) and ischaemic heart disease (IHD) as compared with females. The prevalence of DVT amongst Indians was significantly higher as compared with Whites and Blacks. However, the rate of pulmonary embolism and VTE was lower in Indians as compared with both the races. Amongst the baseline characteristics identified as risk factors for VTE, Indians had a higher prevalence of infection as compared to both Whites and Blacks, but lower HIV infection as compared to Blacks. As compared to Whites, Indians had lower prevalence of idiopathic VTE (but similar to blacks) and had higher prevalence of idiopathic pulmonary embolism (P < 0.0001). This can be explained by different inherited and environment risk factors between these three populations.

JAK2 mutations across a spectrum of venous thrombosis cases.

The JAK2(V617F)mutation is recurrent in polycythemia vera and essential thrombocythemia, which are myeloproliferative neoplasms frequently associated with arterial and venous thromboembolism. It has also been reported as a marker for occult myeloproliferative disorder (MPD) in patients with splanchnic venous thrombosis. Limited data are available regarding the prevalence of the JAK2(V617F) mutation in patients with thrombosis outside the splanchnic region. For the study, 321 cases of venous thrombosis in the splanchnic and nonsplanchnic regions (cerebral venous thrombosis [CVT], 70; deep venous thrombosis [DVT], 36; Budd-Chiari syndrome [BCS], 137; portal venous thrombosis [PVT], 78) were studied for the presence of JAK2 mutations. The prevalence values for the JAK2 mutation were 3% (1/36), 8.8% (12/137), 5% (4/78), and 3% (2/70) in DVT, BCS, PVT, and CVT, respectively; 19 (5.9%) of 321 cases were positive for the JAK2 mutation. Of 111 healthy subjects screened for this mutation, none were found to be carriers. Determination of the JAK2(V617F) mutation may be useful to identify patients who should be carefully observed for the development of overt MPDs. The significance of screening for this mutation in nonsplanchnic thrombosis cases needs to be analyzed in a larger series.

Differences in etiological and clinical manifestations in upper extremity and lower limb deep venous thrombosis patients from India.

We assessed the clinical manifestations in upper and lower limb deep venous thrombosis patients from India and difference in etiological factors. Fifty-three patients with primary upper extremity deep vein thrombosis (UEDVT; males 30, females 23) and 236 patients with lower limb deep vein thrombosis (LLDVT; males 157, females 79) were included in this study. The thrombophilia markers studied were protein C (PC), protein S (PS), antithrombin (AT) III, and factor V Leiden (FVL) mutation. Females had significantly higher prevalence of prothrombotic markers as compared to males (P = .046) in the UEDVT group. No statistically significant differences in the prevalence of prothrombotic markers were observed between the LLDVT and the UEDVT patients. The clinical picture however revealed greater involvement of thrombus of the iliofemoral vein (P = .009) and the proximal tibial vein (P = .005) in males than females, while no differences were observed in the clinical manifestations between the 2 sexes in UEDVT patients. Our study is able to give a broad perspective of the prevalence data of UEDVT and LLDVT in the city of Mumbai of approximately 5 million population served by this hospital. We conclude that the topology of thrombosis in deep vein thrombosis (DVT) patients in India is different from that of the Western countries.