Hyperacute thrombolysis with IV rtPA of acute ischemic stroke: Efficacy and safety profile of 54 patients at a tertiary referral center in a developing country

BACKGROUND

Given the constraints of resources, thrombolysis for acute ischemic stroke (AIS) is under evaluation in developing countries. Prothrombin time (PT), platelet count and activated partial thromboplastin time (aPTT) may not be feasible within the time window.

AIM

To evaluate the safety and efficacy of thrombolysis in selected patients without the coagulation profile.

DESIGN

Open, nonrandomized, observational study.

MATERIALS AND METHODS

Fifty-four stroke patients were classified using TOAST criteria (large artery atherosclerotic = 13; cardioembolic = 12; small vessel occlusion = 22; other determined etiology =three; undetermined etiology = four). The mean time to reach emergency was 2.4h (1.15-3.4), the mean door to CT, 24 min (10-47) and the door to recombinant tissue plasminogen activator (r-tPA) injection, 26.8 min (25-67). The NIHSS scores ranged from 11 to 22 (mean = 15.5 +/- 2.7). Patients with history of liver or renal disease or those on anticoagulants were excluded. The PT, aPTT and platelet count were not done. Recombinant tissue plasminogen activator was administered at a dosage of 0.9 mg/Kg.

RESULTS

Thirty-five patients (65%) significantly improved on NIHSS at 48 h (> or =4 points) (mean change = 10; range= 4-17). At one month, 43 (79%) improved on Barthel Index (mean change = 45%). One each developed small frontal lobe hemorrhage and recurrent stroke; one died of aspiration; and eight showed no improvement.

CONCLUSIONS

Hyperacute thrombolysis was found useful and safe in selected patients with AIS even without the coagulation studies.

Pathology of non-infective gastritis

The discovery of Helicobacter pylori and its intimate role in the development of the most common form of chronic gastritis has elicited a much-needed interest in non-neoplastic gastric pathology. This has been paralleled by an increase in upper endoscopic examinations, which allow recognition of novel patterns and distribution of mucosal injury. Numerous attempts at classification have been made, most based on the acuteness or chronicity of gastric mucosal injury. In this review, we will not offer a new classification but present a detailed description of the major clinicopathological entities, based either on the salient morphological features or the underlying aetiologies, i.e. iatrogenic, autoimmune, vascular or idiopathic.

Nephron sparing surgery: A single institution experience

Objective:

To report our experience in managing various benign and malignant renal tumors with nephron-sparing surgery.

Materials and Methods:

Records of patients who underwent nephron-sparing surgery (NSS) either through open or laparoscopic approach between May 1997 and June 2006 at our institution were reviewed. Patient and tumor-related characteristics, treatment modality and complications were noted.

Results:

There were 26 patients (29 renal units), including three with bilateral lesions who underwent nephron-sparing surgery. Mean age at surgery was 47.0 years (range 16-67 years). Mean tumor size was 4.7 cm (range 2-7.5 cm). Mean warm ischemia time was 41 min and 32.5 min, operative time 158 min and 186 min and blood loss 200ml and 85 ml in open (n=24) and laparoscopic approach (n=2) respectively. Complications were seen in five (19.2%) patients of whom two had postoperative bleeding requiring nephrectomy in one and angioembolization in another. One patient with persistent urinary leak required intervention. Local wound infection in one patient and incisional hernia in another were surgically managed. Histopathological profile revealed 13 (44.8%) benign lesions which included angiomyolipoma (eight), simple cyst (two), cortical adenoma (one), metanephric adenoma (one) and myelolipoma (one). The remaining 16 (55.2%) malignant lesions included renal cell carcinoma (15) and metastatic adenocarcinoma (one). At a mean follow-up of 38.6 months (range 1-91) no patient had local recurrence or distant metastasis. Cancer-specific survival was 100% and overall survival was 92.3%.

Conclusions:

Nephron-sparing surgery is a safe and effective alternative to nephrectomy in both benign and malignant lesions of the kidney.

Adeno-associated virus 2-mediated gene transfer: role of a cellular serine/threonine protein phosphatase in augmenting transduction efficiency

We have documented that a cellular chaperone protein, FKBP52, when phosphorylated at tyrosine and/or serine/threonine (Ser/Thr) residues, interacts with the D-sequence in the inverted terminal repeats of the adeno-associated virus 2 (AAV) genome, inhibits the viral second-strand DNA synthesis, and leads to inefficient transgene expression from recombinant AAV vectors in certain cell types. We have also demonstrated that FKBP52 is dephosphorylated at tyrosine residues by T-cell protein tyrosine phosphatase (TC-PTP), and that deliberate overexpression of TC-PTP leads to more efficient viral second-strand DNA synthesis, and increased transgene expression. However, the identity of the putative Ser/Thr protein phosphatase that dephosphorylates FKBP52 at Ser/Thr residues has remained elusive. Using known inhibitors of Ser/Thr phosphatases, we have now identified protein phosphatase 5 (PP5) to be a candidate enzyme. Deliberate overexpression of PP5 in 293 cells, which does not influence cellular growth, leads to approximately 5-fold increase in the transduction efficiency of conventional single-stranded AAV vectors, but no significant enhancement in the transduction efficiency of self-complementary AAV vectors, suggesting that PP5 plays a role in AAV second-strand DNA synthesis. Electrophoretic mobility-shift assays show that in cells overexpressing PP5, the extent of the complex formation between FKBP52 and the AAV D-sequence is significantly reduced. These studies suggest that PP5-mediated dephosphorylation of FKBP52 at Ser/Thr residues augments viral second-strand DNA synthesis and enhances AAV transduction efficiency, which has implications in the optimal use of these vectors in human gene therapy.

Identification of factor VIII gene mutations in 101 patients with haemophilia A: mutation analysis by inversion screening and multiplex PCR and CSGE and molecular modelling of 10 novel missense substitutions

Haemophilia A (HA) is an X-linked bleeding disorder caused by diverse mutations in the human coagulation factor VIII (FVIII) gene. We have analysed DNA from 109 unrelated Indian patients with HA for their FVIII gene defects. Among these patients 89 (82%) had severe (FVIII:C <1%) HA, 11 (10%) had moderate (FVIII:C 1-5%) HA and nine (8%) had mild (FVIII:C 5-30%) HA. These patients were first screened for the common intron 22 and intron 1 inversions. Inversion negative samples were screened for point mutations by a multiplex PCR and conformation sensitive gel electrophoresis strategy. Mutations were identified in 101 of the 109 patients. These included two (2%) intron 1 and 51 (51%) intron 22 inversions, four (4%) gross deletions and 44 (43%) point mutations. Twenty-nine novel causative mutations, including 11 missense, seven frameshift, five nonsense mutations, three splice site defects and three gross deletions were detected. Ten of the novel missense mutations were studied by molecular modelling. Two different (Thr2253Pro and Pro1392fs) mutations were seen in four unrelated families and FVIII gene haplotyping suggested a common founder effect. Seven of these 109 patients had inhibitors. Among them, four had intron 22 inversions, one had a novel gross deletion (delexon 2-9) and one a nonsense mutation (Trp1535Stop). In one of these patients, no mutation could be identified in the FVIII gene. A Thr2253Pro novel mutation and an intron 22 inversion were identified in two female haemophiliacs. The data from this study suggests that the spectrum of gene defects in Indian patients with HA is as heterogeneous as reported in other populations.

A study of diagnostic yield, technical ease and patient discomfort of low rate repetitive nerve stimulation test in patients with myasthenia gravis

AIM

The diagnostic yield of repetitive nerve stimulation (RNS) study in different muscles has been evaluated in myasthenia gravis (MG) but there is paucity of comprehensive study on technical ease and patient comfort. In this study we evaluate diagnostic yield of RNS test, technical ease and patient discomfort in 8 different muscles in patients with MG.

METHODS

Consecutive patients with MG diagnosed on the basis of clinical evaluation, neostigmine test and/or acetylcholine receptor antibody (AchRAb) assay were subjected to 3 Hz RNS study in abductor digiti minimi (ADM), flexor carpi ulnaris (FCU), anconeus, deltoid, trapezius, serratus anterior (SA), nasalis and tibialis anterior (TA) at rest and 3 min after 30 s exercise. Decrement exceeding 10% was considered abnormal. Patient's discomfort was assessed on a 0-5 scale and technical difficulty by the number of repetitions needed to complete the test or abandonment of test.

RESULTS

Thirty-three patients with MG whose age ranged between 16-81 y were evaluated. At the time of RNS study the predominant weakness was ocular in 3, oculobulbar in 13 and limb in 17 patients. The highest diagnostic yield of RNS test was with deltoid and nasalis (78.8% each), followed by trapezius (65.5%). The highest mean patient discomfort score was with deltoid (2.4), followed by nasalis (1.3). The technical difficulty was maximal in deltoid needing 36.4% repetitions followed by SA (33.3%). In oculobulbar group the best yield was in nasalis (92.3%) followed by deltoid (84.6%), and in limb variety deltoid (82.4%) followed by SA (80%) and trapezius (75%). Combining the diagnostic yield, patient comfort and technical ease; the choice of muscle for RNS should be ADM followed by trapezius for patient with predominant limb weakness, nasalis and trapezius in oculobulbar and nasalis in ocular.

Second echelon node predicts metastatic involvement of additional axillary nodes following sentinel node biopsy in early breast cancer

BACKGROUND

In many patients with early breast cancer, the sentinel lymph node (SLN) is the sole site of regional nodal metastasis. This subgroup of patients may not benefit from completion axillary lymph node dissection (CALND).

AIMS

This pilot study evaluates the status of 2nd echelon (station) lymph nodes in the axilla as a predictor of additional positive nodes in the axilla in the presence of sentinel node metastasis.

SETTINGS AND DESIGN

Cross-sectional study of 40 breast cancer patients.

MATERIALS AND METHODS

Forty patients with invasive breast cancer underwent SLN biopsy followed by 2nd echelon lymph node biopsy in the same sitting. SLN mapping was performed using a combined technique of isosulfan blue and 99 mTc-sulfur colloid. SLNs (Station I) were defined as blue and/or hot nodes. These nodes were then injected with 0.1 ml of blue dye using a fine needle and their efferent lymphatic was traced to identify the Station II nodes. Then a complete ALND was performed. All the specimens were sent separately for histopathological evaluation.

RESULTS

SLNs (Station I nodes) were successfully identified in 98% (39/40) patients. Of the 17 patients with a positive SLN, 8 (47%) patients had no further positive nodes in the axilla, 9 (53%) patients had additional metastasis in nonsentinel lymph nodes upon CALND. Station II nodes were identified in 76% (13/17) patients with a positive SLN. Station II nodes accurately predicted the status of the remaining axilla in 92% patients (12/13).

STATISTICAL ANALYSIS

We calculated the Sensitivity, Negative predictive value, Positive predictive value, False negative rate and Identification rate.

CONCLUSION

Station II nodes may predict metastatic involvement of additional nodes in the axilla.

Hemorrhagic symptoms and bleeding risk in obligatory carriers of type 3 von Willebrand disease: an international, multicenter study

OBJECTIVES

We undertook an international, multicenter study to describe the clinical picture and to estimate the bleeding risk in a group of obligatory carriers of type 3 von Willebrand disease (VWD).

PATIENTS AND METHODS

Obligatory carriers (OC) of type 3 VWD were identified by the presence of offspring with type 3 VWD or by being an offspring of a type 3 patient. Normal controls were age- and sex-matched with the obligatory carriers. A physician-administered standardized questionnaire was used to evaluate hemorrhagic symptoms at presentation. A score system ranging from 0 (no symptom) to 3 (hospitalization, replacement therapy, blood transfusion) was used to quantitate bleeding manifestations. Odds ratios were computed for each symptom.

RESULTS

Ten centers participated to the study, enrolling a total of 35 type 3 VWD families, with 70 OC. A total of 215 normal controls and 42 OC for type 1 VWD were also included. About 40% of type 3 OC had at least one bleeding symptom compared to 23% of normal controls and 81.8% of type 1 OC (P < 0.0001 by chi-squared test), showing that type 3 OC clearly represent a distinct population from type 1 OC. The clinical situations associated with an increase of bleeding risk in type 3 OC were epistaxis [odds ratio 3.6; 90% confidence intervals (CI) 1.84-21.5], cutaneous bleeding (odds ratio 5.5; 90% CI 2.5-14.1) and postsurgical bleeding (odds ratio 16.3; 90% CI 4.5-59). The severity of bleeding score correlated with the degree of factor (F) VIII reduction in plasma.

CONCLUSIONS

OC for type 3 VWD represent a distinctive population from type 1 OC. These patients, however, present with more frequent bleeding symptoms in comparison to normal controls, especially in case of significantly low FVIII. Desmopressin and/or tranexamic acid might be useful to prevent or treat bleeding in these cases.

Update on the pathophysiology and classification of von Willebrand disease: a report of the Subcommittee on von Willebrand Factor

von Willebrand disease (VWD) is a bleeding disorder caused by inherited defects in the concentration, structure, or function of von Willebrand factor (VWF). VWD is classified into three primary categories. Type 1 includes partial quantitative deficiency, type 2 includes qualitative defects, and type 3 includes virtually complete deficiency of VWF. VWD type 2 is divided into four secondary categories. Type 2A includes variants with decreased platelet adhesion caused by selective deficiency of high-molecular-weight VWF multimers. Type 2B includes variants with increased affinity for platelet glycoprotein Ib. Type 2M includes variants with markedly defective platelet adhesion despite a relatively normal size distribution of VWF multimers. Type 2N includes variants with markedly decreased affinity for factor VIII. These six categories of VWD correlate with important clinical features and therapeutic requirements. Some VWF gene mutations, alone or in combination, have complex effects and give rise to mixed VWD phenotypes. Certain VWD types, especially type 1 and type 2A, encompass several pathophysiologic mechanisms that sometimes can be distinguished by appropriate laboratory studies. The clinical significance of this heterogeneity is under investigation, which may support further subdivision of VWD type 1 or type 2A in the future.

Quantitative Determination of Reserpine, Ajmaline, and Ajmalicine in Rauvolfia serpentina by Reversed- Phase High-Performance Liquid Chromatography

A sensitive and reproducible reversed-phase high-performance liquid chromatography (HPLC) method using photodiode array detection is established for the simultaneous quantitation of important root alkaloids of Rauvolfia serpentina, namely, reserpine, ajmaline, and ajmalicine. A Chromolith Performance RP-18e column (100 x 4.6-mm i.d.) and a binary gradient mobile phase composed of 0.01 M (pH 3.5) phosphate buffer (NaH(2)PO(4)) containing 0.5% glacial acetic acid and acetonitrile are used. Analysis is run at a flow rate of 1.0 mL/min with the detector operated at a wavelength of 254 nm. The calibration curves are linear over a concentration range of 1-20 microg/mL (r = 1.000) for all the alkaloids. The various other aspects of analysis (i.e., peak purity, similarity, recovery, and repeatability) are also validated. For the three components, the recoveries are found to be 98.27%, 97.03%, and 98.38%, respectively. The limits of detection are 6, 4, and 8 microg/mL for ajmaline, ajmalicine, and reserpine, respectively, and the limits of quantitation are 19, 12, and 23 microg/mL for ajmaline, ajmalicine, and reserpine, respectively. The developed method is simple, reproducible, and easy to operate. It is useful for the evaluation of R. serpentina.

Adenosine diphosphate ribosylation of dinitrogenase reductase and adenylylation of glutamine synthetase control ammonia excretion in ethylenediamine-resistant mutants of Azospirillum brasilense Sp7

Azospirillum brasilense is a nitrogen-fixing, root-colonizing bacterium that brings about plant-growth-promoting effects mainly because of its ability to produce phytohormones. Ethylenediamine (EDA)-resistant mutants of A. brasilense were isolated and screened for their higher ability to decrease acetylene and release ammonia in the medium. One of the mutants showed considerably higher levels of acetylene decrease and ammonia excretion. Nitrogenase activity of this mutant was relatively resistant to inhibition by NH(4)Cl. Adenosine triphosphate ribosylation of dinitrogenase reductase in the mutant did not increase even in presence of 10 mM NH(4)Cl. Although the mutant showed decreased glutamine synthetase (GS) activity, neither the levels of GS synthesized by the mutant nor the NH (4) (+) -binding site in the GS differed from those of the parent. The main reason for the release of ammonia by the mutant seems to be the fixation of higher levels of nitrogen than its GS can assimilate, as well as higher levels of adenylylation of GS, which may decrease ammonia assimilation.

The nutrient intakes of mothers of low birth weight babies - a comparison of ethnic groups in East London, UK

The objective of this paper was to compare the nutrient intakes of mothers of different ethnic origins after they had given birth to a low birth weight (LBW) baby (< 2.5 kg). A total of 165 participants from East London, UK completed a prospective 7-day diet diary using household measures, between 8 and 12 weeks post-partum. The data were originally collected as baseline data prior to two separate nutrition intervention studies and were combined and re-interrogated for the purpose of this paper. Folate and iron intakes were low in all ethnic groups compared to the Reference Nutrient Intakes (RNI). Half did not meet the RNI for folate and 88% did not meet the RNI for iron. Nearly a quarter of the group did not achieve the Lower Reference Nutrient Intake (LRNI) for iron. The mean vitamin D and calcium intakes were significantly different between the ethnic groups (P = 0.007, P = 0.001, respectively). African women had the highest vitamin D intakes (4.72 microg d(-1)) and Caucasians and Asians the lowest (2.4 microg d(-1)). Caucasians had the highest calcium intakes (780 mg d(-1)) and Africans the lowest (565 mg d(-1)). Over two-thirds of African, Asian and African-Caribbean women did not meet the RNI for calcium. Thirty-one per cent of Africans did not meet the LRNI for calcium. Our data show a high prevalence of inadequate nutrition among women who deliver LBW babies with differences in nutrient intake between ethnic groups. This information can be used to target specific appropriate dietary advice to ethnic minorities for the prevention or repetition of LBW.

Diversity of Glanzmann thrombasthenia in southern India: 10 novel mutations identified among 15 unrelated patients

BACKGROUND

Glanzmann thrombasthenia (GT) is a congenital bleeding disorder caused by either a lack or dysfunction of the platelet integrin alphaIIbbeta3.

OBJECTIVES

To determine the molecular basis of GT in patients from southern India.

PATIENTS

Fifteen unrelated patients whose diagnosis was consistent with GT were evaluated.

RESULTS

Platelet surface expression of alphaIIbbeta3 was < 10%, 10%-50%, and > 50% of controls in five, nine, and one patient(s), respectively. Immunoblotting of the platelet lysates showed no alphaIIb in 14 patients, and no beta3 in 10 patients, although severely reduced in four patients. Platelet fibrinogen was undetectable in 13 patients, and severely reduced in one patient. One patient showed normal surface alphaIIbbeta3 expression, and normal alphaIIb, beta3 and fibrinogen levels in the lysate. Ten novel candidate disease-causing mutations were identified in 11 patients. The missense mutations included Gly128Ser, Ser287Leu, Gly357Ser, Arg520Trp, Leu799Arg in alphaIIb, and Cys575Gly in beta3. We have already shown that Gly128Ser, Ser287Leu, and Gly357Ser mutations variably affect alphaIIbbeta3 surface expression. The Cys575Gly mutation may disrupt the disulphide link with Cys586 to cause the GT phenotype. The molecular pathology of the other missense mutations is not clear. Two nonsense mutations, Trp-16Stop and Glu715Stop in alphaIIb, and a 7-bp deletion (330-336TCCCCAG) in beta3 are predicted to result in truncated proteins. An IVS15(-1)G --> A mutation in alphaIIb induced a cryptic splice site as confirmed by reverse transcription-polymerase chain reaction (RT-PCR) analysis. Thirteen polymorphisms were also identified (five in alphaIIb and eight in beta3), among which five were novel.

CONCLUSIONS

While identifying a significant number of novel mutations causing GT, this study confirms the genetic heterogeneity of the disorder in southern India.

Characterization of the localization and function of NECAP 1 in neurons

NECAPs (adaptin ear-binding clathrin-associated protein) are a new family of clathrin accessory proteins identified through a proteomic analysis of clathrin-coated vesicles (CCVs) from the brain. One member of this family, NECAP 1, is found primarily in tissues from the central nervous system and has been shown to be complexed tightly with a substantial portion of adaptor protein-2 (AP-2) in brain extracts. However, the function and intracellular location of this protein is unknown. In this study, we find that endogenous and epitope-tagged NECAP 1 co-localizes well with clathrin and AP-2 in punctate structures, many of which also contain the presynaptic markers synaptophysin, synaptotagmin or synaptic vesicle protein 2 (SV2). NECAP 1 was also detected by western blot in synaptic vesicle preparations. Overexpression of a truncation mutant of NECAP 1 (BC-NECAP 1) in neurons inhibited transferrin endocytosis but not epidermal growth factor (EGF) endocytosis, and this inhibition was dependent on an AP-2-binding WVQF motif. Moreover, overexpression of BC-NECAP 1 results in inhibition of synaptotagmin endocytosis both in unstimulated neurons and in neurons stimulated with potassium chloride. This inhibition was abrogated by truncation of the WVQF domain. We conclude from these observations that NECAP 1 plays a role in clathrin-mediated neuronal endocytosis, including a role in presynaptic endocytosis.

A Comparative Study of Laparoscopic with Conventional Open Donor Nephrectomy in Renal Transplantation

BACKGROUND

Laparoscopic donor nephrectomy (LDN) has been gaining popularity among kidney donors. There have been concerns about the safety and efficacy of the procedure as compared to open donor nephrectomy (ODN). We compare our results on LDN with ODN.

METHODS

We retrospectively analysed our data of LDN and ODN. Duration of surgery, blood loss, period of hospitalisation, per oral intake and analgesic requirements.

RESULT

22 LDNs were done, the operation time ranged from 220-300 minutes, and blood loss from 100-150ml. In the first 10 laparoscopic operations four cases required conversion to open surgical dissection. Only one case was converted to open surgery in the subsequent 12 laparoscopic cases. Oral intake was started on the first postoperative day. Analgesic requirement in laparoscopy cases was less. Patients were mobilised on the first day after surgery. Patients were discharged by seventh day. There was no significant difference in the functioning of the graft after revascularisation in the recipient.

CONCLUSION

Laparoscopic donor nephrectomy is a safe and effective technique of donor nephrectomy.

Recent developments in clinimetric instruments

Assessment of impairment and function is essential in order to monitor joint status and evaluate therapeutic interventions in patients with haemophilia. The improvements in the treatment of haemophilia have required the development of more sensitive tools to detect the more minor dysfunctions that may now be apparent. This paper outlines some of the recent developments in this field. The Haemophilia Joint Health Score (HJHS) provides a systematic and robust measure of joint impairment. The MRI Scoring System has been designed to provide a comprehensive scoring system combining both progressive and additive scales. The Functional Independence Score for Haemophilia (FISH) has been developed to assess performance of functional activities and can be used in conjunction with the Haemophilia Activities List (HAL) which provides a self report measure of function. It is recommended that both measures are evaluated as these tools measure different constructs. Further refinement and testing of the psychometric properties of all of these tools is in progress. More widespread use of these tools will enable the sharing of data across the world so promoting best practice and ultimately enhancing patient care.

Laboratory issues in bleeding disorders

The clinical history of the patient and of his/her relatives is the most important tool for making correct diagnosis of inherited or acquired bleeding disorders. Several attempts have been made by clinicians to evaluate the sensitivity and specificity of bleeding symptoms. Specific and detailed questionnaires have been designed to quantify the bleeding tendency of patients with von Willebrand's disease (VWD) and a bleeding score has been calculated. VWD is considered the most frequent inherited bleeding disorder according to population studies: however, due to the complexity of its diagnosis, the number of patients with correct diagnosis of VWD in many developing countries is relatively low and most cases remain still under- or misdiagnosed. Once bleeding history is carefully evaluated by means of a bleeding score, the laboratory workout should be organized to find out the specific defect of haemostasis responsible for bleeding. Since factors involved in haemostasis are many, the correct approach must include first level screening tests with the aim to identify the abnormal phase of haemostasis involved: then, second level tests should be focused on the specific factors within the abnormal step of haemostasis. Among many other acquired bleeding disorders related to clinical conditions or to the use of drugs, the acquired inhibitors of haemostasis are rare but should be immediately characterized by appropriate laboratory tests because they can be often life-threatening for the patients.

Fusogenic peptide as diagnostic marker for detection of flaviviruses

BACKGROUND

Dengue, Japanese encephalitis, West Nile encephalitis, yellow fever are the common flaviviral diseases associated with high morbidity and mortality. The initial symptoms of most of the flaviviral infections are similar to each other as well as to some other viral diseases. Making clinical diagnosis, therefore, becomes a challenging task for the clinician. Several studies have been reported on using detection of serum antibodies against flavivirus for the diagnosis of specific flaviviral disease; no field-based pan-flavi virus detection system is available, which can be used in low-endemicity areas for differentiation of flaviviral disease from other viral diseases.

AIM

To identify a conserved amino acid sequence among all flaviviruses and evaluate the antibody formed against the conserved peptide to develop pan-flavivirus detection system.

MATERIALS AND METHODS

In the present study we have compared amino acid sequences of several flaviviruses and identified a conserved amino acid sequence lying in domain II of envelope protein.

RESULTS

A peptide having the conserved amino acid sequence was used to generate polyclonal antibodies and these antibodies were used to detect several flaviviruses. Anti-peptide polyclonal antibodies selectively recognized flaviviruses and did not detect non-flaviviruses. Anti-peptide antibodies detected presence of virus in serum spiked with pure virus preparations.

CONCLUSION

The study offers a rationale for development of pan-flavivirus capture assay suitable for low endemic areas.