An enzyme immunoassay for detection of Japanese encephalitis virus-induced chemotactic cytokine

Japanese encephalitis virus (JEV) induces human peripheral blood monocytes to secrete a chemotactic cytokine [human macrophage-derived factor (hMDF)] which causes chemotaxis of neutrophils. The only known assay for hMDF cannot quantify its level in samples, so an enzyme immunoassay has been standardized for detection of hMDF and hMDF-specific antibodies in test samples. The reported enzyme linked immunosorbent assay (ELISA) was found to be sensitive (89%), specific (91%), accurate (92 2%) and reproducible and was able to detect a minimum concentration of 23 ng hMDF/ml in test samples. The chemotactic factor could be detected in JEV inoculated mouse sera and JEV infected culture fluids. Significant finding of the test was the detection of hMDF in sera of human cases of JE.

A clinical study of the patients with dengue hemorrhagic fever during the epidemic of 1996 at Lucknow, India

This paper describes the clinical findings in 206 patients with dengue fever (DF) or with dengue hemorrhagic fever (DHF) during the epidemic of 1996 at Lucknow. The age group affected most was 11 to 30 years and 21% of the patients were less than 10 years old. The male:female ratio was 1.9:1. The onset was abrupt in all the patients, severe frontal headache was observed in 97%, myalgia in 90%, skin rash in 40%, vomiting in 29% and arthralgia in knee and hip joints in 9%. Anuria was seen in two patients. Lymphadenopathy was noted in 14%, hepatomegaly in 4%, being associated with mild jaundice in one patient, and splenomegaly in 2% of the patients. Involvement of the heart and lungs was seen in one patient each and no case with encephalitis was recorded. Hemorrhages from various sites were observed in 54% patients and 17 patients had profound shock. The commonest bleeding site was gums. Profound shock was preceded by various warning signs, the commonest being sudden hypotension. Among the patients with profound shock the mortality was 47% while the overall fatality rate was 3.8%. A number of the risk factors existed for a long time in this part of the world, but what precipitated the present epidemic at this time, is not known.

Effects of a 99mTc-labeled murine immunoglobulin M antibody to CD15 antigens on human granulocyte membranes in healthy volunteers

An injectible, 99mTc-labeled, murine immunoglobulin M antibody to stage-specific embryonic antigen-1 has been developed that can localize infections by binding to CD15 glycoproteins expressed on the cell membranes of human granulocytes in vivo after systemic administration. The purpose of this study was to measure its clinical effects on healthy people.

METHODS

Multiple blood samples were aspirated before and after the intravenous administration of about 125 microg antibody labeled with approximately 370 MBq (10.0 mCi) 99mTc in 10 healthy human volunteers. Complete blood cell counts were performed at each time point. Whole-body scans were acquired contemporaneously with a dual-head gamma camera. The fraction of the administered dose at each time point was quantified in 18 regions of interest. Statistical analyses included paired t tests.

RESULTS

Administration was associated with a transient decrease in the concentration of red and white blood cells in the whole blood. The effect always began within 3 min of administration. Its nadir was always reached 15-20 min after administration. There was full recovery with mild overcompensation in about an hour. The hematocrit dropped by a mean of 3.8% (P<0.002), whereas the total white blood cell count fell 44.0%+/-3.1% (P<0.001). The effect was most pronounced on the number of circulating granulocytes, which fell from 5.7+/-2.1 to 3.2+/-1.3x10(3)/microL blood. The drop paralleled a decrease in the percentage of whole blood radioactivity bound to the white blood cell membranes, which peaked at 50.4%+/-7.6% at 3 min after injection and then fell to 26.1%+/-9.3% over the next 30+/-13.4 min before recovering to 40.7%+/-8.2% at 2 h. Image analysis showed that the effect was temporally associated with an increase in the amount of radioactivity within the liver and the spleen. Recovery was associated with a decrease in hepatosplenic radioactivity. No evidence of cell destruction or agglutination could be detected.

CONCLUSION

This study confirmed that administration of this radiolabeled antibody is associated with a transient decrease in the number of circulating granulocytes. However, there also seems to be a secondary hemodilutionlike effect on all blood components that has not been reported previously. The effect appears to be clinically silent and very short-lived.

Parkinsonism due to predominant involvement of substantia nigra in Japanese encephalitis

OBJECTIVE

To study the clinical correlates of lesions seen predominantly in the substantia nigra in some patients with Japanese encephalitis (JE).

BACKGROUND

JE typically involves thalamus, brainstem, spinal cord, and cerebral cortex. Rarely, basal ganglia and cerebellum may be affected. Lesions are often widespread and discrete. Predominant involvement of substantia nigra in JE has not been previously reported.

METHODS

Of 52 patients with JE seen in an endemic zone, five were selected on the basis of isolated lesions in the substantia nigra on MRI; all were subjected to detailed clinical and laboratory evaluation.

RESULTS

Presenting symptoms were fever, alteration of consciousness, neck stiffness, and decreased body movements. Examination during acute illness revealed restricted eye movements, opsoclonus, upbeating nystagmus, and cogwheel rigidity. There was early and complete recovery of consciousness and eye signs. Parkinsonian features such as positive glabellar tap sign, masklike face, bradykinesia, tremors, and postural instability became apparent as these patients started walking. Reversible mutism was observed in three patients during the acute phase. Response to levodopa, amantadine, and trihexiphenedyl was partial. Three patients were followed for more than 1 year, during which time their parkinsonian features recovered completely. Substantial recovery was also observed in the two other patients 2 months after regaining consciousness.

CONCLUSIONS

Some patients with Japanese encephalitis may have lesions predominantly in the substantia nigra. After recovery from acute encephalitic illness, they manifest clinically with typical parkinsonian features. Although several viruses are known to cause parkinsonism, this is the first demonstration of a virus producing lesions predominantly in the substantia nigra and causing parkinsonism.

Effects of age on dopamine transporters in healthy humans

99mTc-TRODAT-1 is a new radiopharmaceutical that selectively binds the dopamine transporters. This study characterized the effects of aging on its regional cerebral distribution in healthy human volunteers.

METHODS

The sample consisted of 27 men and 28 women with a mean age of 41.1 +/- 17.1 y (age range 18.7-73.8 y). Dynamic SPECT scans of the brain were obtained with a standardized acquisition and processing protocol on a triple-head camera. Mean counts per pixel were measured in multiple regions of interest within each basal ganglia. Regression analyses were used to relate the specific uptake values at 3-4 h after administration to age. Both linear and nonlinear models of aging were tested.

RESULTS

The relative concentration of radioactivity in most subregions of the basal ganglia decreased significantly with age (all P values < 0.0001). Nonlinear models of aging fit the data significantly better than a straight line. The rate of decline was significantly faster in young adults than in older volunteers (P < 0.001). The break-point age at which the rate of change slowed down and became more stable was 36 y old for the whole striatum and ranged from 32 to 44 y old depending on subregion.

CONCLUSION

The effects of aging on central nervous system dopamine transporters do not appear to be linear. Most effects seem to occur during young adulthood before people reach their 40s. The distribution then appears to remain relatively stable until late in life. The findings suggest that the adult life cycle is better characterized as a series of phases than as a continuum.

Design and characterization of orally active Arg-Gly-Asp peptidomimetic vitronectin receptor antagonist SB 265123 for prevention of bone loss in osteoporosis

The Arg-Gly-Asp (RGD)-binding integrin alpha(V)beta(3) is highly expressed on osteoclasts and has been proposed to mediate cell-matrix adhesion required for osteoclast-mediated bone resorption. Antagonism of this receptor should prevent stable osteoclast adhesion and thereby inhibit bone resorption. We have generated an orally bioavailable, nonpeptide RGD mimetic alpha(v)beta(3) antagonist, SB 265123, which prevents bone loss in vivo when dosed by oral administration. SB 265123 binds alpha(v)beta(3) and the closely related integrin alpha(v)beta(5) with high affinity (K(i) = 3.5 and 1.3 nM, respectively), but binds only weakly to the related RGD-binding integrins alpha(IIb)beta(3) (K(i) >1 microM) and alpha(5)beta(1) (K(i) >1 microM). The compound inhibits alpha(v)beta(3)-mediated cell adhesion with an IC(50) = 60 nM and more importantly, inhibits human osteoclast-mediated bone resorption in vitro with an IC(50) = 48 nM. In vivo, SB 265123 completely blocks bone resorption in a thyroparathyroidectomized rat model of acute bone resorption when dosed at 2.5 mg/kg/h by continuous i.v. infusion. When dosed orally with 3 to 30 mg/kg b.i.d. , in the ovariectomy-induced rat model of osteoporosis, SB 265123 prevents bone resorption in a dose-dependent fashion. This is the first report of an orally active alpha(v)beta(3) antagonist that is effective at inhibiting bone resorption when dosed in a pharmaceutically acceptable fashion. Such a molecule may provide a novel therapeutic agent for the treatment of postmenopausal osteoporosis.

Angioplasty of pedicled right gastroepiploic artery graft through a six French diagnostic catheter

Pedicled right gastroepiploic artery is increasingly being used as a conduit for coronary artery bypass surgery. We describe an interesting case in which balloon angioplasty for stenosis in such a graft was performed through a 6 French diagnostic catheter.

Extracranial vertebral artery stent placement: in-hospital and follow-up results

OBJECT

The authors summarize their experience with stent deployment in the treatment of vertebrobasilar artery (VBA) insufficiency. This is an underdiagnosed condition, and the incidence of significant vertebral artery (VA) stenosis has been underappreciated. Medical therapy has been the mainstay of treatment because of the high rate of morbidity associated with surgical correction of VA stenosis. Recently, some authors have reported acceptable results with the use of percutaneous transluminal angioplasty, but this technique has significant weaknesses such as elastic recoil and problems in achieving safe treatment of dissections.

METHODS

The authors investigated the feasibility, safety, and outcome of VA stent placement in 50 patients in whom 55 vessels were treated using stents. Technical success was achieved in 54 (98%) of 55 vessels, with no procedure-related complications. However, one patient (2%) died of nonneurological causes, and one (2%) suffered a stroke that occurred within the 30-day postprocedural period and was related to a complicated coronary intervention. Clinical follow-up review performed at a mean of 25 +/- 10 months revealed two patients (4%) with recurrence of VBA symptoms. Six-month angiographic follow up was completed in 90% of eligible patients, with a 10% incidence of restenosis as defined by greater than 50% luminal narrowing.

CONCLUSIONS

Vertebral artery stent placement is feasible in patients who have significant VA stenosis, with predictably good angiographically demonstrated and clinical results. The 6-month angiographically confirmed restenosis rate appears to be low, as does the clinical recurrence rate. This technique solves the problems of elastic recoil and the treatment of angioplasty-induced dissections. Further prospective comparison with medical preventive strategies is warranted.

Endogenous mediators and thrombophilia

Platelets are one of the most important components of primary haemostasis. Since they lack a nucleus, their functional characteristics are determined at the time of production. The role of platelets in thrombosis is further modified by the interaction with vascular mediators that are endogenously produced in response to a variety of stimuli. This chapter discusses the factors that influence platelet production, the interaction with endogenous mediators, and the potential therapeutic benefits achieved by modifying this interaction in the clinical setting.

Pulmonary autograft: should it be used in young patients with rheumatic disease?

BACKGROUND

Although pulmonary autograft is being increasingly used to replace the diseased aortic valve with excellent long-term results, its use in the population with rheumatic disease still needs careful evaluation.

PATIENTS AND METHODS

From October 1993 through March 1998, 102 patients underwent aortic valve replacement with a pulmonary autograft (Ross procedure). The mean age was 27.9 +/- 4.2 years (range, 0.8-56 years). The cause was rheumatic disease in 75 patients (73%), bicuspid aortic valve in 26 patients (26%), and myxomatous aortoarteritis in 1 patient (1%). The root replacement technique was used in all. In addition, 31 patients had 33 associated procedures: mitral valve repair (n = 15 patients), open mitral commissurotomy (n = 15 patients), tricuspid repair (n = 2 patients), and homograft mitral valve replacement (n = 1 patient).

RESULTS

Operative mortality was 6.9% (7 patients). Late mortality was 7.8% (8 patients). Follow-up ranged from 1 to 60 months (mean, 25.3 +/- 15.4 months) and was 98% complete. Two patients required reoperation for failed mitral valve repair, and 2 other patients underwent reoperation for failure of both the autograft and mitral valve repair. Echocardiographic assessment showed moderate to severe aortic regurgitation in 13 patients, along with thickening of the autograft. All of these patients had rheumatic disease and were young (<30 years). Ten of these patients had undergone associated mitral valve procedure. Morphologic and histopathologic examination of explanted autografts showed features compatible with rheumatic valvulitis.

CONCLUSION

Pulmonary autograft is susceptible to rheumatic involvement. Young age (<30 years) and associated mitral valve disease are significant risk factors for autograft failure in patients with rheumatic disease. Use of pulmonary autograft in this subgroup of patients requires a cautious approach.

Use of reverse geometry rigid gas permeable contact lenses in the management of the postradial keratotomy patient: review and case report

Radial keratotomy (RK) is a well-known procedure for reducing myopia. However, the complications associated with the procedure and the development of newer technologies, such as photorefractive keratectomy and laser-assisted in situ keratomileusis, has resulted in the technique of RK falling out of favor. A number of patients who received RK during the 1980s are now experiencing a shift in their prescription and are presenting to primary care practitioners for contact lens fitting. These patients pose a significant challenge to the contact lens practitioner, and novel methods frequently are required to fit corneas that exhibit such abnormal topography. This article reviews the potential problems associated with fitting patients who have received RK and describes a case in which a novel lens design was used to achieve a successful lens fit.

Repair of total anomalous pulmonary venous connection in infancy: experience from a developing country

BACKGROUND

Corrective surgery for total anomalous pulmonary venous connection in infancy still carries high morbidity and mortality rates in developing countries. The present study evaluates the factors responsible for it.

METHODS

Seventy-three infants were operated on for total anomalous pulmonary venous connection from January 1987 through October 1997. Age ranged from 5 days to 12 months (mean, 3.9+/-0.24 months), with 10 (13.7%) patients younger than 1 month old. Patient weight varied from 2.0 to 5.2 kg (mean, 3.7+/-0.27 kg). Most (90.5%) patients were small for their ages (< 50th percentile). Anomalous connection was supracardiac in 42 (57.5%), cardiac in 18 (24.7%), infracardiac in 4 (5.5%), and mixed in 9 (12.3%) patients. Thirty-five patients had obstructed drainage. Preoperatively, 30 patients received antibiotic therapy for respiratory tract infection, 3 patients had balloon atrial septostomy, and 4 patients required mechanical ventilation. Fifteen patients (20.5%) were operated on as an emergency procedure. For supracardiac and infracardiac connections, a posterior approach was used for anastomosis. In cardiac type, coronary sinus was unroofed and the resultant defect along with atrial septal defect was closed with a single patch.

RESULTS

The operative mortality rate was 23.3% (17 of 73). Pulmonary hypertensive crisis was the cause of death in 10 patients. Emergency operation and weight less than the 25th percentile were the important risk factors for operative mortality. Young age (< 1 month) and type of drainage did not affect the mortality. Follow-up ranged from 1 to 108 months (mean, 56.4+/-26.0 months). There were two late deaths. The actuarial survival (Kaplan Meier) at 9 years was 72.87%+/-5.39%.

CONCLUSION

Failure of early recognition, and thus delayed referral, accounted for onset of cardiac cachexia, respiratory tract infection, and severe pulmonary hypertension, which had a major effect on unfavorable outcome.

Protease and EGF1 domains of factor IXa play distinct roles in binding to factor VIIIa. Importance of helix 330 (helix 162 in chymotrypsin) of protease domain of factor IXa in its interaction with factor VIIIa

Previous studies revealed that cleavage at Arg-318-Ser-319 in the protease domain autolysis loop of factor IXa results in its diminished binding to factor VIIIa. Now, we have investigated the importance of adjacent surface-exposed helix 330-338 (162-170 in chymotrypsin numbering) of IXa in its interaction with VIIIa. IXWT, eight point mutants mostly based on hemophilia B patients, and a replacement mutant (IXhelixVII in which helix 330-338 is replaced by that of factor VII) were expressed, purified, and characterized. Each mutant was activated normally by VIIa-tissue factor-Ca2+ or XIa-Ca2+. However, in both the presence and absence of phospholipid, interaction of each activated mutant with VIIIa was impaired. The role of IXa EGF1 domain in binding to VIIIa was also examined. Two mutants (IXQ50P and IXPCEGF1, in which EGF1 domain is replaced by that of protein C) were used. Strikingly, interactions of the activated EGF1 mutants with VIIIa were impaired only in the presence of phospholipid. We conclude that helix 330 in IXa provides a critical binding site for VIIIa and that the EGF1 domain in this context primarily serves to correctly position the protease domain above the phospholipid surface for optimal interaction with VIIIa.

Comparison of qualitative and quantitative in vitro ginsenoside production in callus cultures of three Panax species

The qualitative and quantitative difference in the various ginsenoside constituents of the crude butanol-soluble saponin fractions of callus cultures of two Indian species of Panax namely P. sikkimensis and P. pseudoginseng have been compared with that of P. quinquefolium (American ginseng). The 45-50 days old calli of the two Indian species, though found to accumulate crude ginsenoside at levels (0.9% and 1.1%, respectively) comparable to that in P. quinquefolium (1.2%), P. pseudoginseng callus showed high productivity of ginsenosides Rf (40.57%) and Ro (19.60%). P. quinquefolium calli on the other hand accumulated more of Rb and Rg group of ginsenosides but while the former appeared to be a Rg (2) accumulator the callus of the later was rich in the Rg (1) fraction.

Expression of a functional N-methyl-D-aspartate-type glutamate receptor by bone marrow megakaryocytes

Better understanding of hemostasis will be possible by the identification of new lineage-specific stimuli that regulate platelet formation. We describe a novel functional megakaryocyte receptor that belongs to a family of ionotropic glutamate receptors of the N-methyl-D-aspartate (NMDA) subtype responsible for synaptic neurotransmission in the central nervous system (CNS). Northern blotting and reverse-transcriptase polymerase chain reaction (RT-PCR) studies identified expression of NMDAR1 and NMDAR2D type subunit mRNA in rat marrow, human megakaryocytes, and MEG-01 clonal megakaryoblastic cells. Immunohistochemistry and in vivo autoradiographic binding of the NMDA receptor-specific antagonist MK-801 confirmed that megakaryocytes expressed open channel-forming NMDA receptors in vivo. Western blots indicated that megakaryocyte NMDAR1 was either unglycosylated or only glycosylated to low levels, and of identical size to CNS-type NMDAR1 after deglycosylation with endoglycosidase F/peptide-N-glycosidase F. In functional studies, we demonstrated that NMDA receptor activity was necessary for phorbol myristate acetate (PMA)-induced differentiation of megakaryoblastic cells; NMDA receptor blockade by specific antagonists significantly inhibited PMA-mediated increases in cell size, CD41 expression, and adhesion of MEG-01 cells. These results provide evidence for a novel pathway by which megakaryocytopoiesis and platelet production may be regulated.

Radiation dosimetry of a 99mTc-labeled IgM murine antibody to CD15 antigens on human granulocytes

99mTc-labeled anti-stage specific embryonic antigen-1 (anti-SSEA-1) is an injectable IgM antibody derived from mice. It binds to CD15 antigens on some granulocytic subpopulations of human white blood cells in vivo after systemic administration. The purpose of this study was to measure biodistribution of 99mTc-labeled anti-SSEA-1 and perform radiation dosimetry in 10 healthy human volunteers.

METHODS

Transmission scans and whole-body images were acquired sequentially on a dual-head camera for 32 h after the intravenous administration of about 370 MBq (10.0 mCi) of the radiopharmaceutical. Renal excretion fractions were measured from 10 to 14 discrete urine specimens voided over 27.9 +/- 2.0 h. Multiexponential functions were fit iteratively to the time-activity curves for 17 regions of interest using a nonlinear least squares regression algorithm. The curves were integrated numerically to yield source organ residence times. Gender-specific radiation doses were then estimated individually for each subject, using the MIRD technique, before any results were averaged.

RESULTS

Quantification showed that the kidneys excreted 39.5% +/- 6.5% of the administered dose during the first 24 h after administration. Image analysis showed that 10%-14% of the radioactivity went to the spleen, while more than 40% went to the liver. Residence times were longest in the liver (3.37 h), followed by the bone marrow (1.09 h), kidneys (0.84 h) and the spleen (0.65 h). The dose-limiting organ in both men and women was the spleen, which received an average of 0.062 mGy/MBq (0.23 rad/mCi, range 0.08-0.30 rad/mCi), followed by the kidneys (0.051 mGy/MBq), liver (0.048 mGy/MBq) and urinary bladder (0.032 mGy/MBq). The effective dose equivalent was 0.018 mSv/MBq (0.068 rem/mCi).

CONCLUSION

The findings suggest that the radiation dosimetry profile for this new infection imaging agent is highly favorable.

Does platelet glycoprotein IIb/IIIa receptor antibody improve in-hospital outcome of coronary stenting in high-risk thrombus containing lesions?

Coronary stenting in acute coronary syndromes probably increases the risk of acute stent thrombosis. Recently, use of platelet glycoprotein IIb/IIIa receptor antibody has been shown to improve percutaneous transluminal coronary angioplasty (PTCA) outcomes in high risk lesions. The purpose of this analysis was to determine safety and efficacy of platelet glycoprotein IIb/IIIa receptor antibody administration in patients receiving coronary stents in high-risk lesions. Between October 1995 and November 1996, 282 patients with acute ischemic syndromes received coronary stents at our center: 73 had thrombus containing lesions--40 presented with AMI and 33 with unstable angina and make up the study population. The mean age of these patients was 61+/-13 years, 56 were male, 35 had a history of myocardial infarctions (MI), 21 had prior coronary artery bypass graft (CABG), and 21 had prior PTCA. Coronary stenting was used for suboptimal result in 46 patients (63%), threatened closure in 25 patients (34%), and acute closure in 2 patients (3%). Platelet glycoprotein IIb/IIIa receptor antibody was administered during the procedure in 74% and after the procedure in 26%. A total of 115 stents were deployed (Gianturco-Roubin 80, Palmaz-Schatz 29, and Wallstent 6) in 24 LAD, 21 RCA, 15 LCX, and 13 saphenous vein graft (SVG) lesions. Procedural success was 100%. The mean diameter stenosis before and after intervention was 60%+/-31% and 4%+/-14%, respectively. In-hospital events included 1 Q-wave MI (1.4%), 13 non-Q-wave MI (18%), and 1 death (1.4%). There was no subacute stent thrombosis, emergency CABG, or repeat PTCA. Significant in-hospital bleeding complications were noted in seven (10%) patients, with five patients (6.8%) requiring blood transfusions. In this series of patients with acute ischemic syndromes associated with angiographic evidence of thrombus, combined use of platelet glycoprotein IIb/IIIa receptor antibody and stenting resulted in a very low incidence of subacute stent thrombosis and emergency target lesion revascularization. However, bleeding complications were higher than expected with conventional antiplatelet therapy following routine stenting.

Molecular heterogeneity in very-long-chain acyl-CoA dehydrogenase deficiency causing pediatric cardiomyopathy and sudden death

BACKGROUND

Genetic defects are being increasingly recognized in the etiology of primary cardiomyopathy (CM). Very-long-chain acyl-CoA dehydrogenase (VLCAD) catalyzes the first step in the beta-oxidation spiral of fatty acid metabolism, the crucial pathway for cardiac energy production.

METHODS AND RESULTS

We studied 37 patients with CM, nonketotic hypoglycemia and hepatic dysfunction, skeletal myopathy, or sudden death in infancy with hepatic steatosis, features suggestive of fatty acid oxidation disorders. Single-stranded conformational variance was used to screen genomic DNA. DNA sequencing and mutational analysis revealed 21 different mutations on the VLCAD gene in 18 patients. Of the mutations, 80% were associated with CM. Severe CM in infancy was recognized in most patients (67%) at presentation. Hepatic dysfunction was common (33%). RNA blot analysis and VLCAD enzyme assays showed a severe reduction in VLCAD mRNA in patients with frame-shift or splice-site mutations and absent or severe reduction in enzyme activity in all.

CONCLUSIONS

Infantile CM is the most common clinical phenotype of VLCAD deficiency. Mutations in the human VLCAD gene are heterogeneous. Although mortality at presentation is high, both the metabolic disorder and cardiomyopathy are reversible.

Revascularization of a thrombosed, previously stented aorto-renal graft using combined directional atherectomy and AngioJet thrombectomy

We report an interesting case with bilateral PTFE aorto-renal grafts of which one graft underwent balloon angioplasty and stenting for proximal stenosis. Combined debulking by AngioJet thrombectomy and Simpsons directional atherectomy was performed within the stent following reocclusion of the graft 9 months later.

Degradation of Japanese encephalitis virus by neutrophils

The ability of neutrophils to degrade the phagocytosed Japanese encephalitis (JE) virion, via triggering of the respiratory burst and generation of toxic radicals has been investigated. JEV or JEV-induced macrophage derived factor (MDF) induces increase in intracellular oxidative signals with generation of superoxide anion (O2-), via activation of cytosolic NADPH and subsequent formation of hydrogen peroxide, with maximum activity on day 7 post infection. The response was sensitive to anti-MDF antibody treatment. Further, the study revealed rapid degradation of phagocytosed JE viral protein and nucleic acid. The viral protein degradation was partially dependent on the generation of toxic oxygen species as it could be abrogated by pretreatment of the cells with staurosporine.

Biphenylsulfonamide endothelin antagonists: structure-activity relationships of a series of mono- and disubstituted analogues and pharmacology of the orally active endothelin antagonist 2'-amino-N- (3,4-dimethyl-5-isoxazolyl)-4'-(2-methylpropyl)[1, 1'-biphenyl]-2-sulfonamide (BMS-187308)

Substitution at the ortho position of N-(3,4-dimethyl-5-isoxazolyl) benzenesulfonamide led to the identification of the biphenylsulfonamides as a novel series of endothelin-A (ETA) selective antagonists. Appropriate substitutions on the pendant phenyl ring led to improved binding as well as functional activity. A hydrophobic group such as isobutyl or isopropoxyl was found to be optimal at the 4'-position. Introduction of an amino group at the 2'-position also led to improved analogues. Combination of the optimal 4'-isobutyl substituent with the 2'-amino function afforded an analogue (20, BMS-187308) with improved ETA binding affinity and functional activity. Compound 20 also has good oral activity in inhibiting the pressor effect caused by an ET-1 infusion in rats. Doses of 10 and 30 micromol/kg iv 20 attenuated the pressor responses due to the administration of exogenous ET-1 to conscious monkeys, indicating that the compound inhibits the in vivo activity of endothelin-1 in nonhuman primates.

s-IgA and cytokine levels in whole saliva of Sjögren's syndrome patients before and after oral pilocarpine hydrochloride administration: a pilot study

Previous investigations have found elevated levels of s-IgA in the parotid saliva and normal levels in submandibular saliva of patients with Sjögren's syndrome (SS). Fox et al. also found elevated levels of cytokines (i.e., IL-2 and IL-6) in serum, salivary epithelial cells and parotid saliva of patients with SS. The oral administration of pilocarpine hydrochloride stimulates whole and parotid salivary flow. The purpose of this study was to determine the levels of s-IgA and IL-2 and IL-6 in whole saliva before and after administration of pilocarpine hydrochloride in SS subjects. Ten definitively diagnosed SS subjects were enrolled in the study, as were ten controls (C). The mean age was 57.2 years and all subjects were female. Whole unstimulated saliva (WUS) was collected by standard techniques for 5 min, after which the volume and flow rate were determined (mean WUS: SS = 0.047 vs C = 0.480 ml/min). Samples were centrifuged and the immunoglobulin analysis performed on the supernatants by immunoreactivity in a double-sandwich technique as previously described by Rudney et al. Cytokine analysis was performed similarly utilizing commercially available kits from R&D Systems. The results as analyzed by pairwise t-tests revealed comparable levels of s-IgA in the saliva of the SS patients, as compared to controls at baseline (means +/- SEM: SS-IgA = 348.1 +/- 82.0 vs C-IgA = 284.0 +/- 65.1 micrograms/ml; NS). Whole salivary flow was significantly increased (328%) in the SS subject group 60 min after the administration of 5 mg pilocarpine hydrochloride (means +/- SEM: 0.0472 +/- 0.017 vs 0.1546 +/- 0.054 ml/min; P < 0.01). There was no significant change in the concentration of s-IgA in the SS subject group following the pilocarpine dose (means +/- SEM: SS-IgA = 439.9 +/- 121.2 microliters/ml; P = NS). There were elevated levels of IL-2 in the saliva of four out of the ten and IL-6 in two out of the ten SS patients, as compared to controls (means +/- SEM: SS-IL-2 = 127.8 +/- 11.4 vs C-IL-2 = 30.8 +/- 1.6 pg/ml and SS-IL-6 = 41.4 +/- 7.1 vs C-11.6 +/- 2.8 pg/ml). There was also a significant decrease in the concentration of IL-2 in the same four out of ten SS subjects following the pilocarpine dose (means +/- SEM: SS-IL-2 = 32.4 +/- 10.3; P < 0.01). These preliminary results indicate that s-IgA levels do not change with increased salivary flow following the administration of pilocarpine hydrochloride in patients with Sjögren's syndrome. While cytokines are elevated in the whole saliva of some SS patients, a decrease in IL-2 concentration may occur with increased salivary flow.

Elevated levels of IL-8 in dengue hemorrhagic fever

Dengue virus causes dengue fever, a mild febrile illness, and at times dengue hemorrhagic fever (DHF), a severe illness the pathogenesis of which is not fully understood. Given the crucial roles played by interleukin-8 (IL-8) as a chemoattractant cytokine and in inflammatory processes, levels of circulating IL-8 in the sera and IL-8 mRNA in the peripheral blood mononuclear cells (PBMC) were measured in 99 patients of a recent dengue epidemic that occurred in India in 1996 and in 21 normal healthy controls. Twenty-six of the patients had dengue fever (DF) and the remaining 73 were diagnosed as having different grades of DHF. All the control normal sera were negative for IL-8, so were their PBMC for IL-8 mRNA. Increased levels of IL-8 in the sera and IL-8 mRNA in their PBMC were observed in patients with severe illness of DHF grades III and IV. Only two out of 26 patients of DF and one out of 10 DHF grade I patient were positive for IL-8 and all three deteriorated to DHF grade IV within 24 hr. All six patients of DHF grade IV who died had higher serum level of IL-8 above 200 pg/ml, the highest being 5,568 pg/ml in one patient; the presence of mRNA for IL-8 was very high in all patients. A striking correlation was observed between increased levels of IL-8 and severe DHF, with greater levels in patients with increased grade of the disease and death. These results suggest that IL-8 may have an important role and may be an indicator of increasing severity of the disease and death.