Randomized clinical trial of mesh fixation with glue or sutures for Lichtenstein hernia repair

BACKGROUND

Pain is the most likely reason for delay in resuming normal activities after groin hernia repair. The primary aim of this study was to determine whether the use of glue to fix the mesh instead of sutures reduced acute postoperative pain after inguinal hernia repair. Secondary objectives were to compare postoperative complications, chronic pain and early recurrence rates during 1-year follow-up.

METHODS

Some 370 patients who underwent Lichtenstein hernia repair were randomized to receive either glue (Histoacryl®) or non-absorbable polypropylene sutures for fixation of lightweight polypropylene mesh. Postoperative complications, pain and recurrence were evaluated by an independent blinded observer.

RESULTS

Postoperative pain at 8 h, 24 h, 7 days and 30 days was less when glue was used instead of sutures for all measures (P < 0·001). The operation was significantly quicker using glue (mean(s.d.) 35·3(8·7) min versus 39·9(11·1) min for sutures; P < 0·001). There were no significant differences between the groups in terms of postoperative complications, chronic pain and early recurrence at 1-year follow-up.

CONCLUSION

Atraumatic mesh fixation with glue was quicker and resulted in less acute postoperative pain than sutures for Lichtenstein hernia repair. Registration number: NCT02632097 (http://www.clinicaltrials.gov).

[Development of external quality control protocol for CyberKnife beams dosimetry: preliminary tests multicentre]

PURPOSE

To develop an external quality control procedure for CyberKnife(®) beams. This work conducted in Nancy, has included a test protocol initially drawn by the medical physicist of Nancy and Lille in collaboration with Equal-Estro Laboratory.

MATERIALS AND METHODS

A head and neck anthropomorphic phantom and a water-equivalent homogeneous cubic plastic test-object, so-called "MiniCube", have been used. Powder and solid thermoluminescent dosimeters as well as radiochromic films have been used to perform absolute and relative dose studies, respectively. The comparison between doses calculated by Multiplan treatment planning system and measured doses have been studied in absolute dose. The dose distributions measured with films and treatment planning system calculations have been compared via the gamma function, configured with different tolerance criteria.

RESULTS

This work allowed, via solid thermoluminescent dosimeter measurements, verifying the beam reliability with a reproducibility of 1.7 %. The absolute dose measured in the phantom irradiated by the seven participating centres has shown an error inferior to the standard tolerance limits (± 5 %), for most of participating centres. The relative dose measurements performed at Nancy and by the Equal-Estro laboratory allowed defining the most adequate parameters for gamma index (5 %/2mm--with at least 95 % of pixels satisfying acceptability criteria: γ<1). These parameters should be independent of the film analysis software.

CONCLUSION

This work allowed defining a dosimetric external quality control for CyberKnife(®) systems, based on a reproducible irradiation plan through measurements performed with thermoluminescent dosimeters and radiochromic films. This protocol should be validated by a new series of measurement and taking into account the lessons of this work.

Assessment of morphological and molecular similarity of Hungarian white grape varieties

The aim of this paper was to find possible link between molecular and morphological similarities of 38 Hungarian white grape varieties. Three aspects of morphological and molecular similarity were assessed in the study: comparison of the ordered variety pairs, assessment of molecular and morphological mean similarity differences and separation of varieties into similar groups by divisive cluster analysis to define (DIANA). Molecular similarity was calculated from binary data based on allele sizes obtained in DNA analysis. DNA fingerprints were determined at 9 SSR loci recommended by the European GrapeGen06 project. Morphological similarity was calculated on the basis of quantitative morphological descriptors. Morphological and molecular similarity values were ordered and categorized after pairwise comparison. Overall correlation was found to be weak but case by case assessment of the variety pairs confirmed some coincidence of molecular and morphological similarity. General similarity position of each variety was characterized by Mean Similarity Index (MSI). It was calculated as the mean of n-1 pair similarity values of the variety concerned. Varieties were ordered and compared by the difference of the index. Five varieties had low morphological and high molecular MSI meaning that they share several SSR marker alleles with the others but seems relatively distinct according to the expression of their morphological traits. Divisive cluster analysis was carried out to find similar groups. Eight and twelve cluster solutions proved to be sufficient to distinct varieties. Morphological and molecular similarity groups partly coincided according to the results. Several clusters reflected parent offspring relations but molecular clustering gave more realistic results concerning pedigree.

Imaging lid-parallel conjunctival folds with OCT and comparing its grading with the slit lamp classification in dry eye patients and normal subjects

PURPOSE

To visualize and describe the morphologic appearance of lid-parallel conjunctival folds (LIPCOFs) by using optical coherence tomography (OCT) and to relate it to dry eye signs and symptoms.

METHODS

The LIPCOF grade, noninvasive tear film breakup time (NIBUT), lipid layer interference pattern, and dry eye symptoms were recorded in 17 normal subjects and 33 patients with dry eye. LIPCOFs were evaluated with a slit lamp and visualized by OCT. Three different algorithms for OCT were developed to grade LIPCOFs according to tear meniscus height or the covering tear film on the folds.

RESULTS

The three OCT methods showed significant correlation with the slit lamp method (r = 0.470-0.473, P < 0.01). The OCT LIPCOF imaging methods were independent of NIBUT. The Dry Eye Questionnaire (DEQ) scores correlated with the height of the folds and the absence of tear film coverage of the folds (r = 0.574, P < 0.001 and r = -0.527, P < 0.001, respectively). The OCT LIPCOF grades correlated with the DEQ scores (r = 0.494, P < 0.001 and r = 0.310, P = 0.029, respectively). The slit lamp grade did not correlate with the DEQ scores in the whole population, but did in the normal group (r = 0.458, P = 0.024). The OCT LIPCOF grades showed inverse correlation with lipid pattern in the normal group (r = -0.422-0.481, P = 0.05); however, this association disappeared in the dry eye group.

CONCLUSIONS

OCT enabled a noninvasive, high-resolution method of imaging, evaluating, and classifying LIPCOFs. These new classifications correlated well with the slit lamp grade and the DEQ scores, promising a new, more objective evaluation of dry eye.

Kinetic analysis of topographical parameters and interference pattern of tear lipid layer in normal subjects

PURPOSE

To investigate the post-blink changes of the topographical regularity indices, the corneal wavefront aberrations and the tear lipid layer's interference pattern, and analyze the relationship between these parameters' changes.

METHODS

Sequential topographical measurements were recorded on 23 normal participants. The surface regularity index (SRI), surface asymmetry index (SAI), corneal total higher order aberrations (HOA) root mean square (RMS), Coma RMS and Spherical RMS were calculated from the topographical measurement. The incidence of the type 1 (with an initial decrease after blink) alteration trend, and the times to the initial minimum were determined in every parameter. The movement of the tear lipid layer's interference pattern was recorded, and the spreading time of the lipid layer was measured subjectively by three independent observers.

RESULTS

The incidence of the type 1 SRI trend (82%) was the most common among those measured. The average time to the type 1 SRI trends' minimum was 4.05 ± 1.46 s. There was no correlation between the time to the minimum of type 1 trends of the topographical indices, the HOA, Coma and Spherical RMS. The mean lipid layer spreading time was 5.09 ± 1.90 s. We found weak but significant correlation between the times to the minimum of type 1 SRI trends and the lipid spreading time (r = 0.540, p = 0.021).The minimum of the SRI index occurred before the stoppage of superficial lipid layer's motion.

CONCLUSION

Relatively long lipid layer spreading time was observed suggesting that the tear film build-up process did not finish completely at the end of the initial rapid tear film alteration phase. The detected initial decrease of the SRI after blink related to the post-blink tear film motion. This initial pattern is characteristic of the majority of the normal population in spite of the post-blink alteration pattern of the topographical SAI or corneal aberrations. The SRI seems to be the most useful indirect topographical parameter of the tear film dynamics.

[Positron emission tomography using 18-FDG-PET in radiologically indeterminate pulmonary lesions]

OBJECTIVE

Fluorine-18 deoxyglucose Positron Emission Tomography (FDG-PET) is a non-invasive technique that offers the possibility to define if the radiologically indetermined pulmonary lesions are benign or malignant with high positive and negative predictive values. Considering the indexed literature we can observe that there are few original studies performed with the diagnostic possibilities of our means. For this reason, our main objective is to evaluate the diagnostic accuracy of positron emission tomography in sixty-seven radiologically indetermined pulmonary nodular lesions.

MATERIAL AND METHOD

Retrospectively, we evaluated the diagnostic ability of FDG-PET globally (by means of visual and semiquantitative analysis) and partially (only considering the Standardized Uptake Value (SUV)), in sixty-seven patients confirmed by pathology or clinical and radiological monitoring, in a time interval superior to one year.

RESULTS

Globally, FDG-PET had a sensitivity (S) of 92%, specificity (SP) of 86.6%, positive predictive value (PPV) of 89.4%, negative predictive value (NPV) of 89.6% and diagnostic accuracy (DA) of 89%. The best results were obtained for an SUV equal or superior to 2.5. With this value, the clinical efficacy parameters were: S 0.92, SP 0.90, PPV 0.92, NPV 0.90 and DA 0.91.

CONCLUSIONS

We can characterize most of the radiologically indetermined pulmonary lesions by FDG-PET. The additional use of SUV facilitates an increase in the positive predictive value and specificity of FDG-PET.

Elevated antibody levels against Chlamydia pneumoniae, human HSP60 and mycobacterial HSP65 are independent risk factors in myocardial infarction and ischaemic heart disease

The relative significance of traditional risk factors, chronic infections and autoimmune processes in the development of acute myocardial infarction (AMI) has not been fully elucidated. We compared serum IgG antibody titres to various pathogens, i.e. Chlamydia pneumoniae (Cpn), cytomegalovirus (CMV) and herpes simplex virus type 1 (HSV-1), and to the potential autoantigens human heat shock protein 60 (hHSP60) and mycobacterial heat shock protein 65 (mHSP65), in serum samples obtained from patients 3-48 h after AMI (n = 40) or stable effort angina (SEA, n = 43), and from controls (n = 46). The strongest association was observed between AMI and the elevated level of hHSP60 antibodies. The association between AMI and the level of Cpn antibodies was also significant. High levels of hHSP60 and Cpn antibodies represented independent risk factors for the development of AMI, but the simultaneous presence of high levels of antibodies to Cpn and hHSP60 suggested a joint effect on the relative risk of AMI (OR = 12.0-21.1). The antibody titres to mHSP65 were higher in the SEA group than in the controls, and the simultaneous presence of high levels of Cpn and mHSP65 antibodies meant an increased risk among the SEA patients. The antibody titres to CMV or HSV-1 were similar in the three groups. In conclusion, these results demonstrate associations of AMI with high levels of anti-hHSP60 and anti-Cpn antibodies, and of SEA with the level of anti-mHSP65 antibodies, these being independent risk factors.

Epistatic effects of genes encoding immunoglobulin GM allotypes and interleukin-6 on the production of autoantibodies to 60- and 65-kDa heat-shock proteins

Immunoglobulin GM and KM genes have been associated with antibody responses to a variety of antigens. A promoter-region polymorphism of interleukin-6 (IL-6) gene (-174 G/C) has been shown to be associated with antibody responses to heat-shock proteins (hsp) 60 and hsp65. To examine the possible epistatic effects of these unlinked genetic systems on the autoimmune responses to hsp60 and hsp65, 176 healthy Caucasian subjects from Finland were genotyped for several allelic determinants of GM, KM, and IL-6 genes by PCR-RFLP methods. IgG antibodies to hsp60 and hsp65 were measured by an ELISA. Significant interactive effects of GM f,z and IL-6-174 genotypes were noted for both anti-hsp60 (P=0.002) and anti-hsp65 (P=0.038) antibody levels. Since these autoantibodies have been implicated in susceptibility to coronary heart disease and carotid atherosclerosis, the associations reported here might be relevant to the etiology of these diseases.

Changes in tear protein pattern after photorefractive keratectomy

PURPOSE

Changes in tear protein composition of patients who underwent photorefractive keratectomy (PRK) were analyzed.

METHODS

Tear samples were obtained from 23 eyes of 23 patients immediately before PRK and on the fourth postoperative day with glass capillaries. Tear proteins were separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Digital image analysis and evaluation of the densitometric data of the electrophoretic separations were done with BioDoc-Analyze.

RESULTS

Analysis of discriminance found a significant difference in the protein patterns (p < 0.001). This type of analysis of the electrophoretic densitographs uses all peak information simultaneously. A significant decrease (p < 0.005) in three of the main protein peaks--lactoferrin, immunoglobulin A heavy chain, and lysozyme--was also found after PRK.

CONCLUSIONS

Excimer laser ablation of the cornea has an acute effect on lacrimal gland protein secretion. Changes in tear composition may lead to feelings of dryness and to a decrease in tear film stability postoperatively.

Relationship of anti-60 kDa heat shock protein and anti-cholesterol antibodies to cardiovascular events

BACKGROUND

Several recent studies have indicated an association between key inflammatory mediators and atherosclerotic diseases. We evaluated whether high levels of antibodies against heat shock proteins and cholesterol (ACHA) predicted cardiovascular (CV) events.

METHODS AND RESULTS

We used blood samples from the Heart Outcomes Prevention Evaluation (HOPE) study to conduct a nested case-control study of 386 cases with CV events and 386 age- and sex-matched HOPE study controls without events. We explored the relationship between anti-hsp antibodies, ACHA, and subsequent outcomes (incident myocardial infarction, stroke, or CV death) during a mean follow-up of 4.5 years using conditional logistic regression. High levels of anti-hsp65 antibodies (> or =90th percentile) predicted CV events (OR, 2.1; 95% CI, 1.2 to 3.9, P=0.01). Anti-hsp60 antibodies did not predict any event type, whereas incident stroke developed significantly less frequently in patients with high ACHA levels. Anti-hsp antibodies and ACHA did not correlate with inflammatory (fibrinogen, C-reactive protein, interleukin-6, intracellular adhesion molecule-1) or infectious markers (C pneumoniae or cytomegalovirus antibodies). Anti-hsp65 antibodies (> or =90th percentile) and fibrinogen (highest tertile) had a strong joint effect: patients with high concentrations of both had more CV events (OR, 5.5; 95% CI, 1.8 to 17.5, P=0.004) than patients with low levels of both. A similar joint effect (OR, 2.7; 95% CI, 1.3 to 5.7, P=0.01) was found for high levels of anti-hsp65 and presence of cytomegalovirus antibodies.

CONCLUSIONS

Serum antibodies to hsp65 were associated with subsequent CV events in this study of high-risk patients, independent of conventional cardiovascular risk factors and other inflammatory markers.

Helicobacter pylori infection in connective tissue disorders is associated with high levels of antibodies to mycobacterial hsp65 but not to human hsp60

BACKGROUND

To investigate whether the Helicobacter pylori status influences levels of antibodies against mycobacterial heat shock protein (hsp) 65 and human hsp60 in systemic autoimmune diseases and to study the concentration of anti-H. pylori antibodies in autoimmune patients and healthy controls.

MATERIALS AND METHODS

Antibodies against human heat-shock protein hsp60, mycobacterial heat-shock protein hsp65 were analyzed by ELISA. Anti-Helicobacter antibodies were determined by enzyme immunoassay.

RESULTS

There was a markedly higher prevalence of H. pylori infection in undifferentiated connective tissue disease (82%) (n = 33) and systemic sclerosis (78%) (n = 55) but not in systemic lupus erythematosus (n = 49), polymyositis/dermatomyositis (n = 14), rheumatoid arthritis (n = 21) or primary Raynaud's syndrome (n = 26) compared with controls (59%) (n = 349). In autoimmune diseases H. pylori infection was associated with elevated levels of antihsp65 (p =.008) but not of antihsp60. Anti-hsp65 levels were significantly higher in H. pylori-infected (n = 129) than in uninfected patients (n = 69) (p =.0007).

CONCLUSIONS

These findings indicate that in autoimmune diseases the infection with the H. pylori bacterium is associated with increased concentration of antimycobacterial hsp65.

Antibodies against the human heat shock protein hsp70 in patients with severe coronary artery disease

Heat shock proteins (hsps) play complex role in the function of the immune system, they can activate both humoral and cellular immune response, as well the complement system. Although autoimmunity to hsp70 was implicated in certain autoimmune diseases and other conditions, the exact role of anti-hsp70 antibodies is not known. It was demonstrated by our previous work and other's findings that antibodies against the 60 kDa hsps are strongly associated with coronary atherosclerosis and carotis disease. It is also known that there is increased hsp70 expression at different sites of atherosclerosis. Therefore our aim was to study whether level of anti-hsp70 antibodies correlate with the presence of severe coronary artery disease (CAD). We measured and compared anti-hsp70 IgG antibody levels in CAD patients (n = 99) and healthy subjects (n = 99) with ELISA. The frequency of these antibodies was high in both groups and there was no significant difference in the median level of anti-hsp70 antibodies between patients with severe CAD and controls (653 (400-1141) vs. 630 (326-1152) AU/mL, P = 0.337). Adjustment for age, sex, BMI and lipid parameters did not change this result. Furthermore we did not find a correlation between anti-hsp70 antibody levels and certain risk factors of CAD (age, lipid parameters, body mass index, C-reactive protein, gender, smoking, diabetes and anti-hsp60 antibodies). By contrast, in accordance with our previous findings, anti-hsp60 and anti-hsp65 antibody levels were significantly higher in CAD patients, compared to this control group (p < 0.0001 for both variables). We did not find any correlation between the levels of anti-hsp70 and anti-hsp60 or anti-hsp65 antibodies either in the patients or the controls. The exact role of hsp70 in atherosclerosis is controversial, but we suggest that humoral immunity against human hsp70 does not contribute to coronary atherosclerosis in contrast to antibodies against 60kDa hsps.

Impaired humoral immune response against mycobacterial 65-kDa heat shock protein (HSP65) in patients with inflammatory bowel disease

Since only scarce data are available on the immune response against heat shock proteins (HSP) in inflammatory bowel disease (IBD), we have measured with an ELISA method serum levels of IgG, IgA, and IgM antibodies to mycobacterial HSP65 and human HSP60 in 66 patients with Crohn's disease (CD), 42 patients with ulceratiVe colitis (UC), and 126 age-and gender-matched healthy controls. Serum concentration [median (25th-75th percentiles) of IgG anti-HSP65 antibodies was substantially lower in patients with either CD (P < 0.01) or UC (P < 0.001) than in healthy controls, while no difference was found in the levels of anti-HSP60 antibodies. Low anti-HSP65 antibody levels were measured in patients with active CD and in both active and inactive UC, and only in IBD patients with no extraintestinal manifestations. In conclusion, our present findings indicate that an abnormal immune response to bacterial HSP65 or some epitopes of the protein may contribute to the dysregulation of host defenses against certain intestinal bacteria.

Complement activating antibodies against the human 60 kDa heat shock protein as a new independent family risk factor of coronary heart disease

BACKGROUND

Several groups have reported high levels of antibodies against 60 kDa heat shock proteins (hsp) associated with coronary heart disease.

METHODS AND RESULTS

Complement activating (CA) antihsp60 autoantibodies were measured by the AtheroRisk kit (CardioPath Ltd, Alloa, UK), in parallel with IgG antibodies to human hsp60 and mycobacterial hsp65 by ELISA in 32 healthy children (18 boys, 14 girls, 11.8 +/- 4.0 years). At least one of the parents of these children had a history of myocardial infarction before 55 years of age (high family risk (HFR) group). The control group consisted of 63 healthy children (31 boys, 32 girls, 9.0 +/- 3.6 years) without known family history of coronary heart disease (CHD), hypertension, and diabetes mellitus. Concentrations of CA antihsp60 antibodies were significantly (P = 0.021) higher in the HFR group than in the control group. Also in the HFR group, significantly (P = 0.004) lower high-density lipoprotein cholesterol (HDL-C)-cholesterol (measured enzymatically) and significantly (P = 0.020) higher low-density lipoprotein cholesterol (LDL-C)-cholesterol levels (calculated by the Friedewald formula) were observed when compared with the controls. The difference in the CA antihsp60 antibody levels between the HFR and control groups remained significant even after adjustments for age, smoking, HDL-cholesterol, LDL-cholesterol levels, and white blood cell count. Children with high (in the highest quartile) CA antihsp60 antibody levels compared with those with normal levels of these antibodies also had adjusted odds ratios (OR) of 9.80 (2.15-44.58, P = 0.003), indicating high family risk. No significant difference in the IgG antihsp antibody levels was observed.

CONCLUSIONS

These findings indicate that high levels of CA autoantibodies against hsp60 can be considered to be a novel family risk factor of CHD, independent of HDL- and LDL-cholesterol levels.

The promoter polymorphism of the IL-6 gene is associated with levels of antibodies to 60-kDa heat-shock proteins

Elevated levels of antibodies to 60 kDa heat shock proteins are associated with severe coronary heart disease and carotid atherosclerosis. The presence of self hsp60-reacting antibodies can only be partially explained by microbial infections and induction by bacterial hsp65 proteins, since important differences (including the epitope specificity and complement activating ability) between hsp60 and hsp65 reacting antibodies have been shown. The aim of this study was to investigate the possible effects of genetic polymorphisms of different genes of proinflammatory cytokines on anti-hsp60 autoantibody levels. One hundred and seventy-six male blood donors were recruited and antibody levels to human hsp60 and Mycobacterium bovis hsp65 were determined by ELISA. Also in these donors, polymorphisms of the promoter of the IL-6 gene at position -174, the biallelic base exchange of the IL-1 beta gene at the -511 position and the IL-1 alpha gene at position -889 were investigated by PCR. A strong association between IL-6 -174 polymorphism and anti-hsp60 antibody levels was seen; the effect on anti-hsp65 antibody was less marked. Carriers of allele C at this position had significantly lower levels of anti-hsp60 and anti-hsp65 antibodies. A lack of associations between IL-1 beta and IL-1 alpha gene polymorphisms and antibody levels was detected. This is the first study in which associations between genetic polymorphisms and autoantibody levels have been described in healthy subjects. Further studies are needed to gain insight into the detailed mechanism of how the IL-6 gene polymorphism at position -174 influences anti-hsp60 autoantibody levels.

C1r-C1s-C1inhibitor (C1rs-C1inh) complex measurements in tears of patients before and after penetrating keratoplasty

PURPOSE

The aim of this pilot study was to determine the presence of complement activation products in tears from pre- and postkeratoplasty eyes and the fellow eyes in order to investigate the activation of the classical and alternative pathways of the complement system in the early postkeratoplasty period.

METHODS

Tear samples from both eyes of 19 prekeratoplasty patients were tested. From 10 patients, samples were taken before operation, one week and 3 weeks after penetrating keratoplasty. Only baseline and 1 weak samples, and baseline and 3 week samples were available from 5 and 2 patients, respectively, while only baseline tear samples were collected from 2 patients. Tear concentration of two complement activation products, C1rs-C1inh and C3bBbP were determined by enzyme-linked immunosorbent assay.

RESULTS

There was no difference (p = 0.339) between baseline samples of the eyes waiting for operation (0.93 +/- 0.51 AU/ml, mean +/- SEM) and the fellow eyes (0.33 +/- 0.33 AU/ml) in respect of mean C1rs-C1inh complex concentration. The one-week samples of the operated eyes revealed significantly (p = 0.006) elevated levels of C1rs-C1inh complexes (18.8. +/- 6.37 AU/ml), compared to their baseline samples (1.18 +/- 0.64 AU/ml), whereas the one-week values of the fellow eyes did not differ from the baseline values. Compared to the increased one-week values, the three-week values decreased to the baseline values in the operated eyes. C3bBbP could be detected in 3/68 tear samples.

CONCLUSIONS

In our study we demonstrated the increased concentration of C1rs-C1inh complex in several tear samples taken early after human penetrating keratoplasty. These findings provide direct evidence that the classical pathway of complement may be activated in the early postoperative period after penetrating keratoplasty.

High level of anticholesterol antibodies (ACHA) in HIV patients. Normalization of serum ACHA concentration after introduction of HAART

Anticholesterol antibodies (ACHA) are natural antibodies against the 3beta-OH group of cholesterol. Since lipid disorders are common in HIV infection and HAART may further enhance dislipidaemia, we determined by using an ELISA method serum ACHA concentrations in HIV patients and healthy HIV-seronegative controls. ACHA levels were almost 4 times higher in the sera of 46 patients than in 110 controls. No difference in the specificity of ACHA was found between HIV-seropositive and HIV-seronegative sera. Binding of ACHA to cholesterol-coated plates from a HIV-seropositive serum was dose-dependently inhibited by preincubation with HIV-1(BA-L) preparation. Serum concentration of ACHA was significantly higher in the patients with low serum cholesterol levels than in those with normal cholesterol levels. HAART induced a marked drop of ACHA concentration. We found a significant negative correlation between the length of HAART and the ACHA levels. By contrast, HAART did not significantly influence total IgG concentration and titers of antibodies against 60 kD heat shock protein. Our findings indicate that high levels of ACHA in HIV-infection may contribute to the development of hypocholesterolaemia frequently observed in this disease.

Complement activation in the nasal mucosa following nasal ragweed-allergen challenge

The aim of this study was to explore complement activation in the nasal lavage following a nasal ragweed-allergen challenge. The study was carried out with 15 adolescents who were allergic to ragweed and with six non-allergic healthy volunteers. Following the baseline measurement after the symptoms were registered, subjects were given increasing doses of ragweed allergen. Lavage fluid was collected and tested for a complement-activation product (C3bBbP). The allergic patients responded to allergen provocation with an increase in C3bBbP formation compared to the initial lavage (p = 0.001). The C3bBbP level remained low in the lavage fluids of the non-allergic controls. We found a strong correlation between the threshold dose that induced symptoms and the dose where the maximum complement activation was detected (r = 0.78, p = 0.001). Our findings indicate that in allergic patients nasal challenge with ragweed allergen induces a rise in complement activation in the nasal lavage fluid. These results highlight the role of the complement system in the allergic inflammation on the nasal mucosal surface.

On the propagation of long-range dependence in the Internet

This paper analyzes how TCP congestion control can propagate self-similarity between distant areas of the Internet. This property of TCP is due to its congestion control algorithm, which adapts to self-similar fluctuations on several timescales. The mechanisms and limitations of this propagation are investigated, and it is demonstrated that if a TCP connection shares a bottleneck link with a self-similar background traffic flow, it propagates the correlation structure of the background traffic flow above a characteristic timescale. The cut-off timescale depends on the end-to-end path properties, e.g., round-trip time and average window size. It is also demonstrated that even short TCP connections can propagate long-range correlations effectively. Our analysis reveals that if congestion periods in a connection's hops are long-range dependent, then the end-user perceived end-to-end traffic is also long-range dependent and it is characterized by the largest Hurst exponent. Furthermore, it is shown that self-similarity of one TCP stream can be passed on to other TCP streams that it is multiplexed with. These mechanisms complement the widespread scaling phenomena reported in a number of recent papers. Our arguments are supported with a combination of analytic techniques, simulations and statistical analyses of real Internet traffic measurements.