Atypical presentation of Behçet's disease with central nervous system involvement successfully treated with infliximab.

Central nervous system involvement is a rare and serious complication of Behçet's disease (BD). Herein, we describe a patient with an atypical central lesion, who experienced progressive hypesthesia of the right arm and sensory loss of the trigeminal nerve together with intense headache. A repeated biopsy was necessary to conclusively establish the diagnosis of BD. Therapy with infusions of infliximab led to a remarkable full remission. TNFα-blocking therapy was successfully replaced by azathioprine. The present well-illustrated case demonstrates the difficulty of establishing the diagnosis of BD with central nervous system involvement, the dramatic benefit of short given TNF-α-blocking agent, and the long-term remission with azathioprin.

Retention and adaptiveness of photoperiodic EGG diapause in Florida populations of invasive Aedes albopictus.

Female Aedes albopictus, F2-F3 descendents from individuals collected as immatures at 6 geographic sites in the USA during 2008, exposed to short daylengths (10 h of light and 14 h of darkness at 21 degrees C) laid eggs in diapause, whose frequency depended upon population origin. Diapause responses in northern Florida and Illinois were strong, as had been reported approximately 10 years earlier for Ae. albopictus from these regions. For southern Florida, the diapause response was polymorphic, and its mean incidence decreased at 2 of 3 collection sites compared to 10 years earlier. Exposure in the field for 2- to 4-wk intervals in Vero Beach (lat 27 degrees 35'N) during January 2009 revealed that eggs laid by short-day females had significantly higher survivorship, even though <50% were estimated, from laboratory results, to be in diapause. Enhanced desiccation resistance may select for retention of diapause in southern Florida.

Differential Survivorship of Invasive Mosquito Species in South Florida Cemeteries: Do Site-Specific Microclimates Explain Patterns of Coexistence and Exclusion?

Within 2 yr of the arrival of the invasive container mosquito Aedes albopictus (Skuse), the previously dominant invasive mosquito Aedes aegypti (L.) disappeared from many Florida cemeteries. At some cemeteries, however, Ae. aegypti populations seem stable despite Ae. albopictus invasion. We sought to understand this variation in the outcome (exclusion, coexistence) of this invasion, given that previous experiments show that Ae. albopictus is the superior larval competitor. We tested experimentally the hypothesis that climate-dependent egg survivorship differs between exclusion and coexistence cemeteries and that differences in invasion outcome are associated with microclimate. Viability of eggs oviposited in the laboratory and suspended in vases at six cemeteries was significantly greater for Ae. aegypti than for Ae. albopictus, and greater in 2001 than in 2006. Cemeteries differed significantly in egg survivorship of Ae. albopictus, but not of Ae. aegypti, which is consistent with the hypothesis that Ae. albopictus suffers site-specific, climate-driven egg mortality that mitigates the competitive superiority of larval Ae. albopictus. Principal component (PC) analysis of microclimate records from vases during the experiments yielded three PCs accounting for >96% of the variance in both years of experiments. Multivariate analysis of variance of the three PCs revealed significant microclimate differences among the six cemeteries and between exclusion versus coexistence cemeteries. Stepwise logistic regression of egg survivorship versus microclimate PCs yielded significant fits for both species, and twice as much variance explained for Ae. albopictus as for Ae. aegypti in both years. Higher mortalities in 2006 were associated with high average daily maximum temperatures in vases, with lethal thresholds for both species at ≈40°C. From 1990 to 2007, vase occupancy by Ae. albopictus increased and that by Ae. aegypti decreased, with increasing seasonal precipitation at one well-sampled cemetery. Results support the hypothesis that locally variable climate-driven mortality of Ae. albopictus eggs contributes to patterns of exclusion of, or coexistence with, Ae. aegypti.

Endocarditis due to Tropheryma whipplei: rapid detection, limited genetic diversity, and long-term clinical outcome in a local experience.

The characteristic features of Whipple's disease include abdominal pain, diarrhoea, wasting, and arthralgias, with the causative agent, Tropheryma whipplei, being detected mainly in intestinal biopsies. PCR technology has led to the identification of T. whipplei in specimens from various other locations, including the central nervous system and the heart. T. whipplei is now recognized as one of the causes of culture-negative endocarditis, and endocarditis can be the only manifestation of the infection with T. whipplei. Although it is considered a rare disease, the true incidence of endocarditis due to T. whipplei is not clearly established. With the increasing use of molecular methods, it is likely that T. whipplei will be more frequently identified. Questions also remain about the genetic variability of T. whipplei strains, optimal diagnostic procedures and therapeutic options. In the present study, we provide clinical data on four new patients with documented endocarditis due to T. whipplei in the context of the available published literature. There was no clinical involvement of the gastrointestinal tract. Genetic analysis of the T. whipplei strains with DNA isolated from the excised heart valves revealed little to no genetic variability. In a selected case, we describe acridine orange staining for early detection of the disease, prompting early adaptation of the antibiotic therapy. We provide long-term follow-up data on the patients. In our hands, an initial 2-week course of intravenous antibiotics followed by cotrimoxazole for at least 1 year was a suitable treatment option for T. whipplei endocarditis.

Antiaggregatory and proangiogenic effects of a novel recombinant human dual specificity anti-integrin antibody.

BACKGROUND: beta(3)-Integrins are involved in platelet aggregation via alpha(IIb)beta(3) [glycoprotein (GP)IIb-GPIIIa], and in angiogenesis via endothelial alpha(V)beta(3). Cross-reactive ligands with antiaggregatory and proangiogenic effects, both desirable in peripheral vasculopathies, have not yet been described. OBJECTIVES: In vitro and in vivo characterization of antiaggregatory and proangiogenic effects of two recombinant human Fab fragments, with emphasis on beta(3)-integrins. METHODS: Recombinant Fab fragments were obtained by phage display technology. Specificity, affinity and IC(50) were determined by immunodot assays, enzyme-linked immunosorbent assay (ELISA), and Scatchard plot analysis, and by means of human umbilical vein endothelial cells (HUVECs). Functional analyses included ELISA for interaction with fibrinogen binding to GPIIb-GPIIIa, flow cytometry for measurement of activation parameters and competitive inhibition experiments, human platelet aggregometry, and proliferation, tube formation and the chorioallantoic membrane (CAM) assay for measurement of angiogenic effects. RESULTS: We observed specific and high-affinity binding to an intact GPIIb-GPIIIa receptor complex of two human Fab autoantibody fragments, with no platelet activation. Dose-dependent fibrinogen binding to GPIIb-GPIIIa and platelet aggregation were completely inhibited. One Fab fragment was competitively inhibited by abciximab and its murine analog monoclonal antibody (mAb) 7E3, whereas the other Fab fragment bound to cultured HUVECs, suggesting cross-reactivity with alpha(V)beta(3), and also demonstrated proangiogenic effects in tube formation and CAM assays. CONCLUSIONS: These Fab fragments are the first entirely human anti-GPIIb-GPIIIa Fab fragments with full antiaggregatory properties; furthermore, they do not activate platelets. The unique dual-specificity anti-beta(3)-integrin Fab fragment may represent a new tool for the study and management of peripheral arterial vasculopathies.

Advanced Lemierre syndrome requiring surgery.

A 38-year-old homeless man was admitted with a 2-week history of a sore throat, increasing shortness of breath, and high fever. Clinical examination showed enlarged and tender submandibular and anterior cervical lymph nodes and a pronounced enlargement of the left peritonsillar region (Figure 1a). CT scan of the throat and the chest showed left peritonsillar abscess formation, occlusion of the left internal jugular vein with inflammatory wall thickening and perijugular soft tissue infiltration, pulmonary abscesses, and bilateral pleural effusions (Figures 1b-e, arrowed). Anaerobe blood cultures grew Fusobacterium necrophorum, leading to the diagnosis of Lemierre's syndrome. Treatment with high-dose amoxicillin and clavulanic acid improved the oropharyngeal condition, but the patient's general status declined further, marked by dyspnea and tachypnea. Repeated CT scans showed progressive lung abscesses and bilateral pleural empyema. Bilateral tonsillectomy, ligation of the left internal jugular vein, and staged decortication of bilateral empyema were performed. Total antibiotic therapy duration was 9 weeks, including a change to peroral clindamycin. Clinical and laboratory findings had returned to normal 12 weeks after surgery.The patient's history and the clinical and radiological findings are characteristic for Lemierre's syndrome. CT scans of the neck and the chest are the diagnostic methods of choice. F. necrophorum is found in over 80% of cases of Lemierre's syndrome and confirms the diagnosis. Prolonged antibiotic therapy is usually sufficient, but in selected patients, a surgical intervention may be necessary. Reported mortality rates are high, but in surviving patients, the recovery of pulmonary function is usually good.

Does temperature affect the outcome of larval competition between Aedes aegypti and Aedes albopictus?

The superior larval competitive ability of Aedes albopictus has been proposed to explain the recent displacement of Aedes aegyptiby the former species inparts of the southeastern U.S. Ae. aegypti persists, however, in sympatry with Ae. albopictus in urban areas of southern Louisiana, Florida, and Texas, and the impact of larval competition between these species has not been investigated at higher temperatures that may be characteristic of these urban environments. We compared growth and survivorship of the two species at controlled temperatures of 24 degrees and 30 degrees C in water-containing tires under conditions of intra- and interspecific competition and with or without leaf litter. When other variables were controlled statistically, the estimated finite rate of increase (lambda') was significantly higher for both species at the higher temperature, and the proportional increases in lambda' did not differ between species. Therefore, our experiment predicts that by itself, temperatures between 24 degrees and 30 degrees C would not alter the outcome of larval competition. Overall, response measures of Ae. albopictus were more sensitive than those of Ae. aegypti to the litter and species/density variables, although the development ofAe. aegypti females was uniquely retarded by a high density of its own species.

Recombinant anti-idiotypic antibodies inhibit human natural anti-glycoprotein (GP)IIb/IIIa autoantibodies.

Anti-idiotypic antibodies (anti-Id) have been described against idiotypes expressed on various autoantibodies. Since an immunoregulatory effect has been postulated for anti-Id, modulation of the anti-Id response in autoimmune disease may be of interest. In chronic immune thrombocytopenic purpura (AITP), autoantibodies directed mainly against platelet membrane glycoprotein (GP) IIb/IIIa cause platelet destruction by Fc-mediated phagocytosis or by complement lysis. We have previously reported on the generation of two recombinant anti-GPIIb/IIIa autoantibody fragments (PDG-X, PDG-B), that are specific for conformationally intact GPIIb/IIIa and inhibit binding of autoantibodies from patients with AITP. In the present study, we show that anti-GPIIb/IIIa specificities are not limited to a single individual by isolating five additional anti-GPIIb/IIIa autoantibody fragments from a second phagemid Fab library of an unrelated healthy donor. Using soluble Fab of PDG-X and PDG-B as antigens for panning Fab phagemid libraries from healthy human individuals, we isolated anti-Id phage clones specific for PDG-X or PDG-B. In addition they inhibited the binding of PDG-X or PDG-B to GPIIb/IIIa. Amino acid sequence comparison between these specific antiId and GPIIb/IIIa was performed. Generation of these anti-Id directed against pathologically relevant anti-GPIIb/IIIa autoantibodies may represent a new suitable and specific therapeutic option for the treatment of antibody-mediated AITP.

Clinical use of intravenous immunoglobulins.

Prophylaxis and treatment with i.v. immunoglobulins must envisage preparations from normal or hyperimmunised human donors, animals (horses and rabbits) as well as monoclonal and genetically and proteomically engineered chimeric or recombinant antibodies. The latter group of antibody sources from the bioreactor source must be seen in the context of traditional antibody therapy, including passive immunization, general antibody substitution and provision of lost immune regulatory capacities such as downregulation of complement activation, attenuation of Fc receptor apparatus as well as anti-idiotypic potential. Beyond summarizing the present evidence based indications the present review is an outlook at the doorstep for future possibilities to improve precision of antibody dependent treatments and avoiding side effects which formerly compromised widespread use.

IL-4 and IL-10 antagonize IL-12-mediated protection against acute vaccinia virus infection with a limited role of IFN-gamma and nitric oxide synthetase 2.

Resistance or susceptibility to most infectious diseases is strongly determined by the balance of type 1 vs type 2 cytokines produced during infection. However, for viruses, this scheme may be applicable only to infections with some cytopathic viruses, where IFN-gamma is considered as mandatory for host defense with little if any participation of type 2 responses. We studied the role of signature Th1 (IL-12, IFN-gamma) and Th2 (IL-4, IL-10) cytokines for immune responses against vaccinia virus (VV). IL-12-/- mice were far more susceptible than IFN-gamma-/- mice, and primary CTL responses against VV were absent in IL-12-/- mice but remained intact in IFN-gamma-/- mice. Both CD4+ and CD8+ T cells from IL-12-/- mice were unimpaired in IFN-gamma production, although CD4+ T cells showed elevated Th2 cytokine responses. Virus replication was impaired in IL-4-/- mice and, even more strikingly, in IL-10-/- mice, which both produced elevated levels of the proinflammatory cytokines IL-1alpha and IL-6. Thus, IL-4 produced by Th2 cells and IL-10 produced by Th2 cells and probably also by macrophages counteract efficient anti-viral host defense. Surprisingly, NO production, which is considered as a major type 1 effector pathway inhibited by type 2 cytokines, appears to play a limited role against VV, because NO sythetase 2-deficient mice did not show increased viral replication. Thus, our results identify a new role for IL-12 in defense beyond the induction of IFN-gamma and show that IL-4 and IL-10 modulate host protective responses to VV.

[A 26-year-old woman with splanchnic vein thrombosis as the initial manifestation of polycythemia vera]. / Eine 26jährige Frau mit splanchnischer Venenthrombose als Initialmanifestation einer Polycythaemia vera.

A 26-year-old woman, after cesarean section in the 33rd week of gestation, developed after delivery thrombosis of the popliteal vein, pulmonary embolism and thrombosis of the portal vein. After completion of a six month period of oral anticoagulation, laboratory investigations revealed diminished levels of plasminogen and free protein S antigen as well as APC-resistance due to heterozygous FV R506Q mutation. After six uneventful years, abdominal sonography and magnetic resonance examination, performed because of abdominal pain, showed liver cirrhosis with Budd-Chiari syndrome. Additional hematological investigations led to the diagnosis of polycythemia vera. Association of myeloproliferative disorders, mainly polycythemia vera, with splanchnic venous thrombosis is well known and should always be looked for.

Recombinant human natural autoantibodies against GPIIb/IIIa inhibit binding of autoantibodies from patients with AITP.

Autoimmune thrombocytopenic purpura (AITP) is caused by autoantibodies predominantly against platelet membrane glycoproteins (GP) IIb/IIIa and GPIb/IX. Naturally occurring autoantibodies have been described against a variety of autoantigens; it has been suggested that perturbation of their regulation may be associated with autoimmune diseases. Using a combinatorial Fab phagemid library from an individual immunized with human RhD+ red blood cells, we evaluated the presence of natural anti-GPIIb/IIIa autoantibodies as well as their relation to AITP-associated anti-GPIIb/IIIa autoantibodies. Selection on native GPIIb/IIIa and characterization of positive clones by inhibition studies against murine monoclonal anti-GPIIb/IIIa antibodies and by DNA analysis revealed the presence of two distinct recombinant anti-GPIIb/IIIa autoantibodies, which partially inhibited binding of affinity-purified platelet-associated autoantibodies from 8/12 AITP patients. Our results demonstrated that GPIIb/IIIa-specific Fab directed against conformational epitopes within the GPIIb/IIIa complex may be cloned from the genome of an individual immunized with RhD+ red blood cells, who was not affected by AITP. The partial inhibition of binding of platelet-associated autoantibodies from AITP patients to GPIIb/IIIa by the recombinant anti-GPIIb/IIIa phage clones suggests recognition of closely related antigenic epitopes. These phage clones may represent down-regulated, potentially pathological autoantibodies and could be used as new tools for investigation of AITP.

Egg maturation in neotropical malaria vectors: one blood meal is usually enough.

The requirement of more than one blood meal to complete a gonotrophic cycle is reported here to be infrequent among field-collected Anopheles (Nyssorhynchus), including Anopheles darlingi, South America's most important malaria vector. The overall frequencies of host-seeking females that did not develop eggs after one blood feeding were low for Anopheles darlingi (6.6%), Anopheles rondoni (5.0%), and Anopheles triannulatus (2.2%); the majority of wild-caught females that did not develop eggs after one blood meal were nulliparous. Laboratory-reared Anopheles albimanus and Anopheles albitarsis, other species of the same subgenus, were grown on enriched and impoverished larval diets to yield a range of adult sizes and to examine relationships between egg maturation, body size, and blood meal intake. 10.7% of nulliparous An. albimanus and 22.9% of An. albitarsis failed to mature eggs after sugar and one blood meal, and shorter wings and smaller blood meals predisposed females to require multiple blood feeds for egg maturation. Unmated An. albitarsis were significantly more likely than mated females not to develop eggs. Multiple blood meals within a single gonotrophic cycle appear to be less important in the life histories of neotropical Nyssorhynchus species compared to afrotropical malaria vectors.

Long-term dynamics of a predator used for biological control and decoupling from mosquito prey in a subtropical treehole ecosystem.

We identified, staged and counted the immature stages of mosquitoes from 1,826 censuses (with replacement) of the aquatic contents of ten treeholes surveyed every 2 weeks between 1978 and 1993. These time series were used to examine the population dynamics and effect on prey of the predatory mosquito Toxorhynchites rutilus. The mean annual frequency of occurrence of T. rutilus ranged from 0.02 to 0.67 among holes, and no fourth instars were recovered during a 30-month dry period. Oviposition and pupation by this species were recorded in all months, but most commonly in the spring. Overwintering larvae of the predator increased in weight during the prolonged fourth instar that preceded pupation in the spring. Time series analyses showed that the presence of a fourth instar T. rutilus significantly reduced the abundances of late-stage Aedes triseriatus mosquitoes. Pupal numbers of this prey species were more negatively affected by T. rutilus than were numbers of fourth instar A. triseriatus. Long-term declines in mean annual abundance of A. triseriatus prey during 16 years of observations on two holes were not correlated with increases in the mean annual frequencies of T. rutilus. Local extinctions of the aquatic stages of A. triseriatus within treeholes were common, but in most holes not significantly associated with the presence of T. rutilus, suggesting that predation does not routinely drive mosquito prey locally extinct in this ecosystem. The decoupling of T. rutilus and A. triseriatus, as revealed through these complete and long-term censuses, is contrasted with other reports of generalist predators causing extinctions of mosquito prey. Discrepancies among reported outcomes probably result from differences in duration of sampling periods and statistical procedures along with real differences in the intensity of predation among systems and sites.

Seasonal abundance, age composition, and body size of salt-marsh Anopheles (Diptera: Culicidae) in south Florida.

Five CO2-baited light traps operated fortnightly between November 1989 and May 1991 near a salt marsh in Vero Beach, FL, caught 1,961 Anopheles crucians Wiedemann (s.l.) and 691 An. atropos Dyar & Knab. Both species were most abundant in winter and least abundant in summer; their numbers correlated inversely with lagged mean ambient temperatures. Annual parous rates were 55% for An. crucians and 58% for An. atropos and varied little seasonally. Wing lengths of female An. crucians measured for eight consecutive months were negatively correlated with ambient temperatures, and parous females of this species had significantly longer wings than nullipars. Parous rates and wing length classes were positively correlated among An. crucians, confirming that larger mosquitoes are longer-lived.

Spin-echo and STIR MR imaging of sports-related muscle injuries at 1.5 T.

Seventy patients with clinically diagnosed athletic muscle injuries of varying severity were studied with MR imaging at 1.5 T. Twenty underwent follow-up MR studies. In all cases, SE T1-weighted and double-echo T2-weighted pulse sequences were used. These were supplemented by short T1 inversion recovery (STIR) sequence in 36 cases. Muscle injuries were more readily seen with STIR images than with SE T2-weighted images. In both initial assessment and follow-up of tears, the use of the STIR technique allowed the greatest lesion/muscle contrast. Short TR, short TE SE images provided anatomic detail and were an adjunct to T2-dependent SE images in the evaluation of organized hematomas (11 cases). Follow-up MR studies in 20 patients at variable time intervals allowed demonstration of regression of the tear in 11 cases, fibrous scar formation in 5 cases, and recurrence of the tear in 4 cases. Evolution of hematomas into scar and into cyst was demonstrated in three and two cases, respectively. Owing to the additive effect of T1 and T2 mechanisms, the STIR sequence is well suited for initial evaluation and can replace T2-weighted images in the follow-up of muscle trauma.

Characteristics of angiotensin converting enzyme and its role in the metabolism of angiotensin I by endothelium.

Angiotensin converting enzyme (ACE) was isolated from rabbit lung tissue by affinity chromatography on an N-(1-carboxy-5-aminopentyl)-L-alanylglycine resin. The molecular weight of the enzyme was determined to be 140,000, and upon isoelectric focusing a set of bands between pH 4.3-4.7 was observed. When the enzyme was treated with endoglycosidase F the molecular weight decreased to 100,000, and a virtually identical molecular weight was found for the in vitro translated form of ACE. The ACE-catalyzed hydrolysis of angiotensin I was followed by high-performance liquid chromatography separation and fluorescence monitoring of substrate and products. The kinetic parameters of the angiotensin I hydrolysis were KM = 17 mumol/L and kcat = 420 min-1 at pH 7.5. By the same analytical method the metabolism of angiotensin I by cultured endothelial cells and by the isolated, perfused rabbit aorta was investigated. Only a small fraction of angiotensin I was converted to angiotensin II; the larger part was directly degraded to small peptides. In the presence of ACE inhibitors no angiotensin II was formed but the rate of the angiotensin I hydrolysis was virtually unchanged. Thus, the action of ACE is critical to the generation of angiotensin II but not to the degradation of angiotensin I, and during ACE inhibition no accumulation of angiotensin I occurs.