Efficacy and safety of tixagevimab-cilgavimab (Evusheld®) in people with Multiple Sclerosis on Ocrelizumab: preliminary evidence

BACKGROUND

Evusheld (EVS) was authorized by FDA and EMA as pre-exposure prophylaxis (PrEP) in people at high risk of severe Covid-19 outcomes, including people with Multiple Sclerosis (pwMS) on B-cell depleting (BCD) therapies-such as Ocrelizumab (OCR). In this population, no data on possible adverse drug reactions (ADRs) to EVS, B-lymphocytes (CD20 +) counts pre- and post-EVS injection, and comparison of percentage increase of IgG antibodies directed against SARS-CoV-2 trimeric spike protein (anti-TSP IgG) post-EVS and Covid-19 vaccine was available. The aim of this study was to better characterize the efficacy and safety profile of EVS in pwMS on BCD agents.

METHODS

17 pwMS on OCR agreed to receive EVS as PrEP for Covid-19. Sera samples were collected before the first dose of Covid-19 vaccine (T0), 4 weeks after the second dose (T1), 4 weeks after third dose (T2), immediately before (T3) and 4 weeks after (T4) EVS.

RESULTS

Covid-19 vaccine ADRs were mild-to-moderate, whereas no ADRs were reported after EVS injection. A significant increase of anti-TSP IgG was found only at T0-T1 (Z = -3.059, p = .002) and T3-T4 (Z = -3.621, p < .001) time-points. The median percentage increase between T3-T4 was significantly higher with respect to the T0-T1(Z = -3.296, p = .001) and T1-T2 (Z = -3.059, p = .002) time-points.

CONCLUSIONS

These results further support EVS safety and efficacy in boosting anti-TSP IgG titers in pwMS on OCR, with a statistically greater increase than that observed after completion of a full Covid-19 vaccine cycle, plus a booster dose.

Non-contrast MR dacryocystography for the evaluation of epiphora and recurrent dacryocystitis: A preliminary study

INTRODUCTION

Obstruction of the lacrimal drainage represents a common ophthalmologic issue. The blockage may interest any level of the lacrimal drainage pathway, and it is important to find the site of obstruction to plan the most appropriate treatment. In this study, findings from magnetic resonance (MR) dacryocystography were compared with findings from endoscopic and surgical procedures to evaluate the accuracy of MR dacryocystography in localizing the site of nasolacrimal duct obstruction.

METHODS

We enrolled twenty-one patients with clinical suspicion of nasolacrimal duct obstruction who underwent dacryoendoscopy and surgery. MR dacryocystography was performed with a heavily T2-weighted fast spin echo sequence in the coronal planes. Before the MRI was performed, a sterile 0.9% NaCl solution was administered into both conjunctival sacs. For each examination, two independent readers (with 8 and 10 years of experience in head and neck imaging) evaluated both heavily 3D space T2-weighted and STIR sequences.

RESULTS

Stenosis/obstruction of nasolacrimal duct or lacrimal sac was diagnosed in all 21 patients who underwent MRI dacryocystography. In particular, the site of the obstruction was classified as lacrimal sac in 12 (57%) patients, nasolacrimal duct in 6 (29%) patients, and canaliculi in 3 (14%) patients by both readers. By comparison with the evidence resulting from the endoscopy, there were differences between MRI dacryocystography and dacryoendoscopy in the evaluation of the obstruction's site in three patients, with an overall accuracy of 85.7%.

CONCLUSION

MR dacryocystography allows a non-invasive evaluation of the lacrimal drainage pathway, valid for the planning of the most appropriate treatment.

Prevalence and Distribution of High- and Low- Risk HPV Genotypes in Women Living in the Metropolitan Area of Naples: A Recent Update

INTRODUCTION

Human papillomavirus (HPV) can infect both male and female genitals, skin, and mucous membranes, causing benign or malignant lesions. HPV is a common sexually transmitted infection and it is the main cause of cervical cancer. The present retrospective study updated the previously published data on HPV genotypes distribution among women living in Naples.

MATERIALS AND METHODS

In this study, 502 cervical scrape specimens were collected from women with abnormal cytological indication and analyzed for HPV DNA identification by Linear Array HPV genotyping test.

RESULTS

The HPV infection rate was 24.1%. HPV-16 (14.6%) was the most representative HR-HPV genotypes, followed by HPV-31 (13.8%), -18 (9.2%), and HPV-51 (8.5%). In addition, HPV-42 (16.4%) was the most prevalent genotype among LR-HPV  genotypes (low-risk human papillomavirus). It was also found that women at the age group of 23-29 years (42.5%) were at the highest risk of HPV infection. It was found that the HPV-16 frequency decreased, but HPV-31 and -18 frequency increased a little. The LR HPV-53 frequency decreased, leaving the first place for abundance to the LR HPV-42. HPV-6 frequency did not change. LR HPV -11 was no more present. Merging <23 and 23-29 age classes into one class followed the same result.

CONCLUSION

HPV prevalence declined in comparison to the previous data. A frequency variation was recorded for several genotypes in this study.  Data can be useful to implement the preventative strategies and to promote HPV vaccination.

Humoral response and safety of the third booster dose of BNT162b2 mRNA COVID-19 vaccine in patients with multiple sclerosis treated with ocrelizumab or fingolimod

BACKGROUND

The assessment of the safety and the humoral response to a third booster dose of the BNT162b2 mRNA COVID-19 vaccine is relevant in patients with Multiple Sclerosis (pwMS) treated with Ocrelizumab (OCR) or Fingolimod (FNG).

METHODS

Serum samples were collected from Healthy controls (HCs) and pwMS treated with OCR or FNG at the following time-points: before the first of two vaccine doses (T0); 8 (T1), 16 (T2), 24 (T3) weeks after the first dose; within 8 weeks before (T0b) and after (T1b) the booster dose. IgG antibodies to SARS-CoV-2 trimeric spike protein (Anti-TSP IgG) were quantified and expressed as binding antibody units (BAU)/mL.

RESULTS

40 HCs, 28 pwMS on OCR and 19 on FNG were included. At T0b 12 (42.9%) pwMS on OCR and 6 (31.6%) on FNG were still positive while, at T1b 16 (57.14%) pwMS on OCR and 16 (84.2%) on FNG, passed the threshold of positivity. The increase of Anti-TSP IgG levels at T1b was higher for: (i) HCs with respect to OCR (p < 0.001) and FNG (p = 0.032) groups; (ii) pwMS on FNG compared with pwMS on OCR (p < 0.001). No socio-demographic, clinical or laboratory variables were able to predict the anti-TSP IgG increase between T0b and T1b. Neither clinical relapses nor severe adverse events were reported in pwMS after each dose of vaccine.

CONCLUSIONS

The third booster dose of BNT162b2 mRNA vaccine to OCR- and FNG-treated pwMS revives the humoral response, independently of any clinical variable, and manifests a good safety and tolerability profile.

Six-month humoral response to BNT162b2 mRNA COVID-19 vaccine in people with multiple sclerosis treated with natalizumab

BACKGROUND

Few studies investigated the immune response to SARS-CoV-2 vaccine in patients with multiple sclerosis (pwMS) treated with natalizumab (NTZ) and found a short-term efficient humoral response; however, there are no studies assessing the levels of SARS-CoV-2 IgG antibodies in pwMS treated with NTZ over time.

METHODS

Humoral immune response to BNT162b2 mRNA COVID-19 vaccine was assessed in a group of 26 pwMS on NTZ up to 6 months after a full COVID-19 vaccination cycle and compared it with 43 age- and sex-matched group of HC. Serum samples were collected before the first dose (T0), and 4 weeks (T1) and 6 months (T2) after the first dose of BNT162b2 mRNA COVID-19 vaccine. The LIAISON® SARS-CoV-2 TrimericS-IgG assay (DiaSorin-S.p.A.) was employed for the detection of IgG antibodies to SARS-CoV-2 spike protein (cutoff for positive IgG antibodies: 33.8 BAU/mL).

RESULTS

At T1 and T2, both groups showed an efficient humoral response to BNT162b2 mRNA COVID-19 vaccine. A significant reduction of IgG antibodies to SARS-CoV-2 spike protein was detected at T2 both in pwMS and in HC, but SARS-CoV-2 IgG antibodies were still above the cutoff limit in all participants.

CONCLUSIONS

pwMS on NTZ develop and maintain a long-term humoral response after a full COVID-19 vaccination cycle comparable to their healthy peers, and these findings are relevant for clinicians called to counsel about COVID-19 mRNA vaccine timing and booster doses in pwMS treated with NTZ.

Six-month humoral response to mRNA SARS-CoV-2 vaccination in patients with multiple sclerosis treated with ocrelizumab and fingolimod

INTRODUCTION

Real-world clinical data suggest an attenuated short-term humoral response to SARS-CoV-2 vaccines in patients with multiple sclerosis (pwMS) receiving high efficacy (HE) disease modifying therapies (DMTs) such as Ocrelizumab (OCR) and Fingolimod (FNG). Long-term humoral response in pwMS treated with these HE-DMTs has been poorly investigated. The aim of our study was to explore: i) the humoral response up to six months after a full cycle of the BNT162b2 mRNA Covid-19 vaccine in pwMS treated with OCR and FNG and to compare it to age- and sex-matched healthy controls (HCs); ii) the relationship between humoral response and clinical and immunological characteristics of the studied population.

METHODS

Serum samples were collected from HCs and pwMS treated with OCR or FNG at the following time points: before BNT162b2 mRNA Covid-19 vaccine (T0), and 4 (T1), 8 (T2), 16 (T3) and 24 (T4) weeks after the first dose. Sera were stored at -20 °C and tested for the quantitative detection of IgG antibodies to SARS-CoV-2 trimeric spike protein (Anti-TSP IgG) expressed in binding antibody units (BAU). At T1 neutralizing antibodies (NAbs) titres were assessed. The relationship between Anti-TSP IgG at each time-point and clinical and laboratoristic analyses were analysed by the Spearman correlation coefficient.

RESULTS

47 HCs and 50 pwMS (28 on OCR and 22 on FNG) were included in the study. All HCs mounted a positive humoral response at T1 and preserved it up to six months. At T1 only 57.1% pwMS on OCR (p < 0.001 compared with HCs) and 40.9% on FNG (p < 0.001) had a positive humoral response at T1, with only 39.3% and 27.3% maintaining a positive response at sixth months (T4), respectively. A strong positive correlation was observed between Nabs titres and Anti-TSP IgG at T1 (rho 0.87, p < 0.0001) with NAbs titres significantly higher in HCs compared with pwMS on OCR and FNG (p<0.0001). We also found a strong positive correlation between time-window since last OCR infusion and anti-TSP IgG titres at all time-points (T1 rho=0.58, p = 0.001; T2 rho=0.59, p = 0.001; T3 rho=0.53, p = 0.004; T4 rho=0.47, p = 0.01). In the FNG group we observed a significant correlation between the humoral response measured from T1 to T4 and: i) treatment duration (T1: rho -0.65, p = 0.001; T2: rho -0.8 p< 0.001; T3: rho -0.72, p=<0.001; T4: rho -0.67, p<0.001), ii) disease duration (T1: rho -0.5, p = 0.017; T2: rho -0.6, p = 0.003; T3: rho -0.58, p = 0.005; T4: rho -0.57, p = 0.006), and iii) baseline total lymphocyte count (T1: rho 0.37, p = 0.08; T2: rho 0.45, p = 0.03; T3: rho 0.43, p = 0.04; T4: rho 0.45, p = 0.03).

CONCLUSIONS

Our long-term data show a weakened and short-lasting humoral response to SARS-CoV-2 mRNA vaccine in pwMS treated with OCR and FNG when compared with HCs. MS neurologists should take into account the time elapsed since the last infusion for pwMS on OCR, and the lymphocyte count as well as the disease and treatment duration for those on FNG when called to counsel such pwMS regarding the vaccination with the SARS-CoV-2 mRNA vaccine.

Varicocele embolization with sclerosing agents leads to lower radiation exposure and procedural costs than coils: Data from a real-life before and after study

Objectives

To investigate clinical outcomes, radiation exposure and procedural costs associated with percutaneous varicocoele embolization using coils and sclerosing agents (SAs) in a cohort of young‐adult men.

Materials and methods

Data from consecutive men treated with percutaneous varicocoele embolization using coils and SA between 2017 and 2021 were analyzed. The allocation was based on a change of policy occurred in June 2020 with the substitution of coils with SA (before and after study). Semen analysis values were based on 2010 WHO reference criteria. Anatomic variants of gonadal veins were categorized according to Jargiello et al. Intraoperative radiation dose and procedural costs were collected for each patient. Descriptive statistics and linear regression models were used to describe the association between clinical parameters with procedural costs and radiation exposure.

Results

One hundred sixteen men were included, of whom 76 (65.5%) received coils, and 40 (34.5%) received SA. Baseline characteristics of the two study groups did not differ. A type 3 Jargiello anatomic variation of left gonadal vein was found in 45.7% of cases. Radiation dose was lower in the SA group as compared to the coils one (13.2 [7–43] vs. 19.8 [12–57] Gy/cm²; p < 0.001). Similarly, procedural costs were lower for the SA group (169.6 [169–199] € vs. 642.5 [561–775] €; p < 0.001). At follow‐up, pain and sperm variables significantly improved in both groups (p < 0.01), without differences among the embolic materials. Linear regression model revealed that coils use was associated with higher radiation exposure (beta 8.8, p = 0.02) than SA after accounting for anatomic variation of gonadal vein, body mass index, and vascular access.

Conclusions

SA and coils for varicocoele embolization are equally safe and effective. The use of SA was associated with lower radiation exposure and procedural costs than coils. These results should be considered in terms of public health cost and patient's safety.

Preliminary evidence of blunted humoral response to SARS-CoV-2 mRNA vaccine in multiple sclerosis patients treated with ocrelizumab

Objectives

Several concerns regard the immunogenicity of SARS-CoV-2 vaccines in people with multiple sclerosis (pwMS), since the majority of them is treated with immunomodulating/immunosuppressive disease modifying therapies. Here we report the first data on the humoral response to mRNA SARS-CoV-2 vaccine in a case series of 4 pwMS treated with ocrelizumab (OCR) as compared to a group of healthy subjects (HS).

Methods

We collected serum samples at 0, 14, 21 days after the first dose and 7 days after the second dose of BNT162b2-mRNA-Covid-19 vaccine from 55 health-care workers and 4 relapsing pwMS on OCR, with no history of Covid-19 infection. Sera were tested using the LIAISON®SARS-CoV-2 TrimericS-IgG assay (DiaSorin-S.p.A.) for the detection of IgG antibodies to SARS-CoV-2 spike protein. The anti-spike IgGtiters were expressed in Binding Antibody Units (BAU), an international standard unit.

Results

At baseline all subjects were negative for anti-spike IgG. Seven days after the second dose of vaccine all HS mounted a significant humoral response (geometric mean 2010.4 BAU/mL C.I. 95% 1512.7-2672) while the 4 pwMS showed a lower response (range <4.81-175 BAU/mL).

Discussion

Humoral response to BNT162b2-mRNA-vaccine in pwMS treated with OCR was clearly blunted. Further data are urgently needed to confirm and expand these preliminary results and to develop strategies to optimize the response to SARSCoV-2 vaccines in pwMS on OCR.

Tuberculosis Infection Screening in 5468 Italian Healthcare Students: Investigation of a Borderline Zone Value for the QFT-Test

Healthcare workers are at an increased risk of contracting Mycobacterium tuberculosis infection. Tuberculin skin test (TST) and interferon gamma release assay (IGRA) represent the available tests most used for the diagnosis of latent tuberculosis infection (LTBI). Different borderline zones have been proposed for defining conversions and reversions to improve the interpretation of the IGRA test results as part of serial testing. From 2012 to 2017, 5468 health students of an Italian University Hospital were screened for tuberculosis infection through the execution of the TST and, in case of positivity, of the QuantiFERON-TB® Gold In-Tube assay (QFT-GIT). The QFT-GIT is considered "borderline" with values from 0.35 to 0.99 IU/mL. Among the students who performed the QFT-GIT assay, 27 subjects presented a range of values defined as borderline. The QFT-GIT was repeated after 90 days on 19 subjects with borderline values and showed a negativization of the values in 14 students and a positive conversion in three cases, while for two students, a borderline value was also found for the second test, with a 74% regression of the borderline cases. The introduction of QuantiFERON borderline values is a useful assessment tool to bring out LTBI case candidates for chemoprophylaxis.

Distribution of Hepatitis C Virus Genotypes and Subtypes in the Metropolitan Area of Naples, Italy, in the Era of Interferon-Free Regimens

AIMS

The objective of this work was to study the distribution of hepatitis C virus (HCV) genotypes and subtypes from 2010 to 2015 in 1,221 anti-HCV/HCV-RNA-positive specimens from patients living in the metropolitan area of Naples, since HCV genotypes and subtypes remain cornerstones in the management of chronic HCV infection even in the directly acting antivirals era.

METHODS

The study was carried out on 1,221 anti-HCV/HCV-RNA-positive plasma samples collected between April 2010 and December 2015.

RESULTS

Of the 1,221 patients enrolled, 633 (51.9%) were males and 588 (48.1%) were females, with a mean age of 60 ± 13 (SD) years. The most frequent HCV genotype observed was genotype 1 (68.1%; 1b in 55.3% and 1a in 9.5%); HCV genotype 2 was found in 289 samples (23.67%), genotype 3 in 6.47%, genotype 4 in only 19 samples, and only 2 samples were classified as genotype 5. The mean age of the patients with genotype 1a or 3 was lower (51 ± 12 and 49 ± 12 years, respectively) than those with genotype 1b (62 ± 11, p < 0.0001 for both) or 2 (62 ± 14, p < 0.0001 for both).

CONCLUSIONS

The data from the present study suggest that HCV genotype 1b remains the most prevalent in this area, followed by genotype 2, 1a, and 3a.

Serum Levels of Granulocyte Macrophage Colony Stimulating Factor (GM-CSF) in a Group of Patients with Systemic Sclerosis

In this report we investigate the behaviour of the serum levels of Granulocyte Macrophage Colony Stimulating Factor (GM-CSF) in the course of Systemic Sclerosis (SS). This cytokine is produced mainly by T and NK cells, and its possible role in the pathogenesis of SS has not been previously described in the literature. Serum GM-CSF levels were assayed in 10 female patients, ageing from 35 to 70, affected by SS. These patients were not suffering from other disorders and were not being treated with steroids or immunosuppressive drug. A solid phase immunoenzymatic method was used to assess the serum levels of GM-CSF. Reference values were previously determined in a control group of 36 healthy women blood donors (19 premenopausal and 17 postmenopausal) (x̄=20.1 ±12.3 pg/ml). All the patients but one showed significantly increased serum levels of GM-CSF (x̄= 120.9 ±125.5 pg/ml). The highest levels were found in the two oldest patients, who also had the longest clinical history of SS, but a clear correlation with age, disease duration or clinical manifestations was not evident, even if the postmenopausal age group patients showed a higher mean value of GM-CSF (x̄= 148.0±144.1 pg/ml) than that found in the premenopausal age group (x̄= 57.7±1.4 pg/ml) (in contrast with the findings in the control group). The absence of other pathogenic conditions in our patients suggests that the increase in serum levels of GM-CSF might be linked to the fibroblast proliferation which is typical of SS. However, our results do not explain the role played by this factor in the fibroblastic proliferation process and an in vitro study is necessary to clarify this aspect.

Spin-torque resonant expulsion of the vortex core for an efficient radiofrequency detection scheme

It has been proposed that high-frequency detectors based on the so-called spin-torque diode effect in spin transfer oscillators could eventually replace conventional Schottky diodes due to their nanoscale size, frequency tunability and large output sensitivity. Although a promising candidate for information and communications technology applications, the output voltage generated from this effect has still to be improved and, more pertinently, reduces drastically with decreasing radiofrequency (RF) current. Here we present a scheme for a new type of spintronics-based high-frequency detector based on the expulsion of the vortex core in a magnetic tunnel junction (MTJ). The resonant expulsion of the core leads to a large and sharp change in resistance associated with the difference in magnetoresistance between the vortex ground state and the final C-state configuration. Interestingly, this reversible effect is independent of the incoming RF current amplitude, offering a fast real-time RF threshold detector.

Understanding of Phase Noise Squeezing Under Fractional Synchronization of a Nonlinear Spin Transfer Vortex Oscillator

We investigate experimentally the synchronization of vortex based spin transfer nano-oscillators to an external rf current whose frequency is at multiple integers, as well as at an integer fraction, of the oscillator frequency. Through a theoretical study of the locking mechanism, we highlight the crucial role of both the symmetries of the spin torques and the nonlinear properties of the oscillator in understanding the phase locking mechanism. In the locking regime, we report a phase noise reduction down to -90  dBc/Hz at 1 kHz offset frequency. Our demonstration that the phase noise of these nanoscale nonlinear oscillators can be tuned and eventually lessened, represents a key achievement for targeted radio frequency applications using spin torque devices.

Assessment of host defence mechanisms induced by Candida species

Some species of Candida are opportunistic pathogens that can cause disease in a host immunocompromised by underlying local or systemic pathological processes. C. albicans is the species most often associated with oral lesions, but other species of Candida, including C. glabrata, C. tropicalis and C. parapsilosis, have also been isolated in the saliva of subjects with and without candidiasis. In the present study we evaluated the host defence mechanisms induced by Candida albicans and other Candida species in monocytes and oral epithelial cells in order to establish the existence of a species-specific cellular response. Our results indicated that, during Candida species infection, the epithelial cells actively participate in the host defence by producing antimicrobial peptides and proinflammatory cytokines. Moreover, in infections caused by Candida tropicalis and Candida glabrata, the host defence may be strengthened by the release of perforin and granzyme by polymorphonuclear leukocytes recruited at the site of infection.

In-vitro Analysis of Antifungal Activity of Epigallocatechin-Gallate: Preliminary Study

Oral candisosis is an heterogeneous group of diseases, caused by different species of Candida fungus. The incidence of drug-resistant species is increasing dramatically; furthermore, in recent years higher incidences of non-albicans and antimycotic-resistant species of Candida have been reported, thus increasing necessity of a non-antibiotic agent, which should be both highly effective and safe. It has been showed that the main polyphenols component of green tea, epigallocatechin-gallate (EGCG), has antibacterial activity; recently, it has been reported its antifungal activity too. We tested the effectiveness of a 0.20% EGCG (TEAVIGO®) gel, a non-pharmaceutical product suitable for oral in vivo use, on four species of Candida yeast (C.albicans, Cparapsilosis, C.tropicalis, C.glabrata), evaluating its antifungal activity and its capacity to inhibit biofilm formation. The EGCG gel showed a remarkable activity against C. parapsilosis and C. tropicalis. This preliminary study confirms EGCG effectiveness on fungi; for this reason, a product with such a low concentration of EGCG could be used with no side-effect for every-day oral hygiene. Anyway, mechanisms of antifungal activity of EGCG are not comprehended and need further studies to better understand the reasons of some Candida species' resistance.

Circulating levels of cytochrome C, gamma-glutamyl transferase, triglycerides and unconjugated bilirubin in overweight/obese patients with non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease, characterized by hepatocyte apoptosis, is distinct in fatty liver and non-alcoholic steatohepatitis, the more severe form. Apoptotic cell death is caspase-dependent and associated with mitochondrial membrane depolarization and cytochrome c release. Adhering to the hypothesis that the exposure of hepatocytes to free fatty acids, resulting in increased ROS production and mitochondrial damage, is balanced by the presence of antioxidant substances, circulating levels of gamma-glutamyl transferase, cytochrome c, triglycerides and unconjugated bilirubin were explored in patients suffering from non-alcoholic fatty liver disease with different severity. One hundred and eighty-six consecutive patients who presented recent ultrasound feature of bright liver without any liver disease of known origin were enrolled, eighty-nine of whom underwent liver biopsy. Forty-five subjects were allocated on the basis of histology in fatty liver group while 44 patients formed the group with non-alcoholic steatohepatitis. A cohort of 27 young, lean, apparently healthy individuals was selected as control group. The levels of gamma-glutamyl transferase were normal or slightly increased, while unconjugated bilirubin concentrations were elevated in all the spectra of non-alcoholic fatty liver disease. Comparing the present results with relevant findings from other studies dealing with diseases characterized by apoptosis, we did not find high circulating levels of cytochrome c in non-alcoholic fatty liver disease. What is more, our patients, categorized as suffering from simple fatty liver or from the more severe non-alcoholic steatohepatitis, had similar levels of cytochrome c and gamma-glutamyl transferase, p=0.19 and 0.11. Serum triglycerides were higher in patients with non-alcoholic fatty liver disease than in the healthy group, p=0.001. These findings likely reflect a balance between oxidative stress and anti-oxidant response rather than a lack of reliability of cytochrome c as a reliable biomarker of mitochondrial damage.

Does spleen volume play a role in patients with HCV-related chronic hepatitis?

As the lymphotropism of hepatitis C virus (HCV) has already been ascertained, and in the light of the fact that the immune defense system is an organized network composed of functionally interrelated tissues, this study was carried out to verify the possible involvement of spleen in HCV-related chronic hepatitis. In this cross-sectional study we measured spleen longitudinal diameter by ultrasound, beta2-microglobulin serum levels and splenic artery resistivity index (SARI) by Doppler in 51 patients treated with standard combined (Peg-Interferon plus Ribavirin) antiviral therapy. Thirty-three patients (17 females) completed the regimen and were compared to 31 controls (16 females). The mean basal values of spleen longitudinal diameter were higher in patients with chronic hepatitis than in controls, i.e., 116 mm (9.4) versus 102.7 mm (9.3), P = 0.0001. In the same patients a significant trend towards increased spleen longitudinal diameter was found after antiviral therapy, independently of the stage of HCV-related chronic hepatitis. The median values of the beta2-microglobulin concentrations were not significantly higher in the patients with HCV-related chronic hepatitis compared to controls, i.e., 1.3 (0.5-2.6) versus 1 (0.6-1.4), P = 0.16, although during the course of therapy they were significantly increased. SARI values of HCV-related chronic hepatitis patients were different from those of controls, but were unvaried compared to values at the end of treatment. Neither spleen measurements nor serum beta2-microglobulin levels were able to predict therapeutic response to antiviral therapy. A stimulation/expansion of lymphoid tissue was found in patients with HCV-related chronic hepatitis. Such evidence raises the question whether physicians should continue to prescribe antiviral therapy in non-responders and supports the use of a new scheme (SLD plus beta2-MG) to diagnose this ongoing, apparently reversible, but nevertheless dangerous immunologic process.

Quinine sulfate inhibits invasion of some bacterial skin pathogens

BACKGROUND

As some of the many patients who receive antimalarials for the treatment of noninfective inflammatory diseases (lupus erythematosus, collagen vascular diseases, rheumatoid arthritis, and others) are also immunosuppressed because of their disease and/or treatments, and may have concomitant bacterial infections, we investigated the effect of these drugs on the growth and invasion of several bacteria that are commonly associated with skin and soft tissue infections to determine whether they could protect against such conditions and obviate the need for an additional antibiotic drug.

METHODS

The effect of quinine sulfate (QS) at concentrations of 50 and 100 microm on the entry process of Enterobacter agglomerans, Staphylococcus aureus, Pseudomonas aeruginosa, and Klebsiella pneumoniae into Caco-2 cells was studied during the infection period. The invasive efficiency was expressed as the number of viable internalized bacteria obtained by counting the colony-forming units (CFUs).

RESULTS

The invasive ability of E. agglomerans and S. aureus was significantly inhibited by 50 and 100 microm QS in a dose-dependent manner when the drug was added to Caco-2 cell monolayers during the infection period; however, QS had no significant effect on the internalization of P. aeruginosa or K. pneumoniae.

DISCUSSION AND CONCLUSIONS

Antimalarial drugs are currently widely used to treat patients with autoimmune dermatologic and rheumatologic diseases, and have also been recently proposed as additional therapy for patients with human immunodeficiency virus (HIV) infection. These patients, who are often immunocompromised, may receive a secondary advantage from these antimalarials, which may provide some protection against staphylococci (amongst the most important human pathogens causing many superficial and systemic infections) and E. agglomerans.

Quinine sulfate inhibits invasion of Salmonella typhimurium and Shigella flexneri: a preliminary study

BACKGROUND

The incidence of typhoid fever and shigellosis parallels that of malaria, so many individuals who are on antimalarial drugs can be found in areas where these diseases are widespread. We investigated the effect of quinine sulfate on the growth and invasion of Salmonella typhimurium and Shigella flexneri M90T to determine whether people on antimalarials can have secondary gain from some protection against typhoid fever and shigellosis.

METHODS

The effect of 50 and 100 microM quinine sulfate on the invasive ability of Salmonella typhimurium and Shigella flexneri M90T into human colon adenocarcinoma-2 (Caco-2) cells was studied during the infection period. The invasive efficiency was expressed as the number of viable internalized bacteria by counting the colony-forming units.

RESULTS

The invasive ability of Salmonella typhimurium and Shigella flexneri M90T was significantly inhibited by 50 and 100 microM quinine sulfate in a dose-dependent manner (for Salmonella typhimurium) when the drug was added to Caco-2 cell monolayers during the infection period.

CONCLUSIONS

Since so many people who are on antimalarial drugs visit and inhabit areas that are endemic to typhoid fever and Shigella infection, a study on the influence of these drugs on the disease is long overdue. Our data indicate that quinine sulfate interferes with the invasion and internalization of Salmonella typhimurium and Shigella flexneri M90T into host cells. Further studies on additional strains/serotypes with other newer antimalarials at various concentrations are needed to verify this effect of quinine sulfate and to draw conclusions on its significance in vivo.

Evaluation of the monocyte counting by two automated haematology analysers compared with flow cytometry

The aim is to determine the monocyte count performance of the Bayer Diagnostics ADVIA120 and Coulter LH 750 automated haematology analysers and the results obtained by these two instruments were compared with those provided by Becton Dickinson FACScan flow cytometer using the combination of CD45/CD14 MoAb. Linearity and imprecision were also evaluated. The linearity of both instruments was good. Coulter LH 750 showed better precision (4.3%) than ADVIA 120 (9.0%) both within and between batch. A significant correlation (r = 0.973) was found between the LH 750 and the flow cytometry method, while a modest one was observed between the latter and the ADVIA 120 (r = 0.880). When comparing the percentage of monocytes by means of one-way anova and Tukey test, it was found that the LH 750 provided the closest results in comparison with flow cytometry, with no statistical difference between the means (mean difference MO% = 0.6); however the difference was statistically different between the ADVIA 120 and flow cytometry (mean difference MO% = -4.06). These data were confirmed by Altman-Bland and Deming regression analyses.

Bacterial components induce cytokine and intercellular adhesion molecules-1 and activate transcription factors in dermal fibroblasts

This study investigated the effect of various structural components of Gram-positive (lipotheichoic acid and protein A) and Gram-negative (porins and lipopolysaccharide) bacteria on human dermal fibroblasts. Fibroblasts are important effector cells which have a potential role in augmenting the inflammatory response in various diseases. In this study we present a profile of TNF-alpha, IL-6 and IL-8, the expression of intercellular adhesion molecules (ICAM-1) and the activation of transcriptional nuclear factor NF-kB and AP-1 in human dermal fibroblasts stimulated by bacterial surface components. Compared to the controls, increased ICAM-1, IL-6 and IL-8 gene expression after stimulation of LPS and porins at 2 and 4 h was more evident than that obtained following stimulation of LTA and PA. Gene expression was also associated with the production of cytokine proteins in culture supernatants. TNF-alpha gene expression remained undetectable. Moreover, LPS and porin treatments determined IkBalpha phosphorylation and degradation in human dermal fibroblasts and the subsequent activation of nuclear factors NF-kB and AP-1. These data suggest the importance of such stimuli in the first step of the inflammatory process, as well as the important role played by fibroblasts in skin inflammatory disease.

[Postpartum perineal assessment]

BACKGROUND

To evaluate the incidence of urogenital and anorectal dysfunctions during puerperium, verify the correlation between obstetric perineal damage observed during labour and puerperal symptoms, test the efficacy of tests to evaluate perineal function in pelvic floor dysfunctions consequent to vaginal birth.

METHODS

A total of 693 consecutive puerperae were recruited two months after birth. All completed a clinical and anamnestic questionnaire and underwent clinical urogynecological examination, digital test, vaginal manometry and uroflowmetric evaluation of the voluntary capacity to interrupt micturition. From a statistical point of view, persistent urinary incontinence was identified by graphic representation on frequency tables and predictive tests, and statistical "kappa" was used to evaluate the correlation between perineal function tests.

RESULTS

Stress urinary incontinence (15.1%) represents the most widespread symptom, a postpartum perineal inspection provides a sufficiently accurate estimate of posterior damage, but does not identify those puerperae who will develop urinary incontinence. None of the tests used was able to predict persistant urinary incontinence.

CONCLUSIONS

Postpartum perineal inspection seems to be effective in predicting anorectal dysfunctions, but is not so useful for urethro-vesical disorders. None of the diagnostic methods examined allowed a sufficiently accurate selection of those puerperae at risk.

The urine stream interruption test and pelvic muscle function in the puerperium

OBJECTIVES

This study assesses the role of the uroflowmetric urine stream interruption test (UST) in the evaluation of postpartum pelvic floor muscle function.

METHOD

Two months after vaginal delivery, 492 women who underwent a digital test, vaginal manometry, and a UST were divided into two groups: continent and incontinent. Variables were subjected to the Student's t-test and to Fisher's exact test to verify the difference between the two groups.

RESULTS

Digital test and vaginal manometry results were higher in the continent group, but only the UST showed significantly different values (P=0.001). All test results of incontinent puerperae who underwent rehabilitation were significantly improved after treatment.

CONCLUSIONS

UST is low cost, non-invasive, and can give objective information about pelvic floor performance after a vaginal delivery. It can be used for both routine clinical use and an outcome measure for women who undergo rehabilitation treatment.

[Magnetic resonance (MR) in endometrial carcinoma preoperative evaluation]

BACKGROUND

Myometrial invasion of endometrial carcinoma is an important prognostic factor because the degree of myometrial invasion is correlated with the rate of lymphnode metastases and of recurrences. The aim of the study was a preoperative evaluation of endometrial carcinoma by Magnetic Resonance (MR).

METHODS

The authors present a prospective study performed on 54 cases of endometrial carcinoma collected at the Department of Gynecology and Obstetrics of the University of Trieste (Italy). All the patients were considered as Stage I after hysteroscopy and endocervical curettage. Prior to surgery all the patients underwent MR at the Department of Radiology of the University of Trieste (Italy) in order to evaluate the depth of myometrial invasion. The surgical procedure included total abdominal hysterectomy, bilateral salpingo-oophorectomy and pelvic and lomboaortic lymphadenectomy in high risk cases. Statistical evaluation was performed by Fischer's exact test.

RESULTS

Statistically significant positive correlation was found (p<0.001) between MR staging and surgical staging. The sensitivity reported in our series for distinguishing between superficial disease (Stage IA and IB) and deep myometrial invasion (Stage IC) was 92%.

CONCLUSIONS

Preoperative MR is helpful in selecting patients at high risk of nodal involvement and it is suggested that, although MR is considered an expensive examination, its use should be always considered before surgical treatment of patients with high surgical risk.

[Typification of HPV in clinical practice]

OBJECTIVE

To improve the sensitivity of cervical carcinoma screening and to determine the optimal management with an ASCUS Pap result we evaluated the effectiveness of combining thin layer cytologic slides (ThinPrep) and HPV DNA testing.

METHODS

A total of 170 women were studied with conventional Pap smears, liquid based cytology, HPV testing and colposcopy with eventual histologic evaluation.

RESULTS

The ThinPrep method yielded 12.5% more high grade lesions than did the conventional smears (and more severe diagnoses as compared to the conventional smears). HPV prevalence was significantly associated with disease status. Of 30 patients with ASCUS, HPV testing detected 100% of high grade lesions and 67% of low grade. If colposcopy had been limited to HPV+ women, 47% of case would have been spared.

CONCLUSIONS

Liquid based cell collection improves sensitivity for the detection of disease. For women with ASCUS cytology, HPV DNA testing of residual specimen can identify the majority of high risk cases using a single sample.

[Sexually transmitted diseases in adolescence]

BACKGROUND

Sexually transmitted diseases (STD) have their most incidence in adolescence. We conducted an observational study on the symptomatic patients of our STD's office to evaluate epidemiological distribution, behavioral patterns and diffusion of genital infections in teen-agers in respect of the adult population.

METHODS

From april 1996 to april 1999 we studied two groups of patients: 54 teen-agers (13-19 years) and 917 women in fertile age (20-40 years). All the patients underwent to a clinical and microbiological examination of vaginal secretions (Gram slide, wet mount, cultures for bacteria, yeasts, eventually Chlamydia trachomatis, Mycoplasma spp, Neisseria gonorrhoeae, Herpes simplex virus--HSV--) and to an anamnestic and socio-epidemiological questionnaire.

RESULTS

The more frequent genital infections among adolescents was vulvovaginal candidiasis (35% vs. 23.9% of adult people). HSV was found in 1.8% of teen-agers (vs. 0.6%) and when requested, Chlamydia trachomatis and mycoplasmas was found respectively in 16.6% (vs. 1.1%) and 50% (vs. 28%) in adolescents. We observed a high percentage of pregnancy (22.2%) of voluntary pregnancy interruption (41.6%) and a specific sexual behavior among teenagers.

CONCLUSIONS

Our data show a particular behavioral risk pattern in the adolescence population and indicate the necessity of a serious program of prevention and sexual education that allow young people to live with more consciousness and safety their sexuality.

[Gynecologic infections in adolescence]

BACKGROUND

Adolescence in the age bracket with the highest incidence of sexually transmitted diseases (STDs). An observational study was performed in symptomatic patients attending our Outpatient Clinic for STDs in order to evaluate the diffusion of genital infections in the adolescent population and the different epidemiological distribution compared to adults.

METHODS

The incidence of these infections was compared in two groups of patients attending the clinic between April 1995 and April 1999. The first consisted of 54 teenagers (13-19 years-old) and the second, used as a control, consisted of 917 women of child-bearing age (20-40 years). All patients underwent clinical examinations and microbiological tests of vaginal secretions (bacterioscopic test on coloured plates using the Gram method, cold tests, cultural assay of bacteria and fungi, assay for (Chlamydia trachomatis, Mycoplasma spp., Neisseria gonorrhoeae, Herpes simplex virus).

RESULTS

The most common genital infection in teenagers was candidosis (35% vs 23.9%), followed by bacterial vaginosis (31.9% vs 25.8%) and mixed flora vaginitis (25.9% vs 22.6%). HSV was found in 1.8% of adolescents (vs 0.6%), in selected cases, Chlamydia and Mycoplasma were present in 16.6% (vs 1.1%) and 50% (vs 28%) of teenagers respectively.

CONCLUSIONS

All genital infections were more frequent in the study population of adolescents compared to the control group. The adolescent population should be the target of a serious and systematic programme of prevention in order to ward off the sequelae of early and often irresponsible sexual activity.

[Sexual behavior and adolescence]

BACKGROUND

Adolescence represents the period with the highest frequency of negative consequences associated with sexual activities (sexually transmitted diseases and unwanted pregnancies). An epidemiological study was carried out in symptomatic patients attending our Outpatient Clinic for Sexually Transmitted Diseases between April 1995 and April 1999 in order to evaluate the behaviour pattern of the adolescent population and identify the differences compared to the adult population.

METHODS

A questionnaire was used to assess the characteristics of two groups of patients: the first consisted of 54 teenagers (13-19 years-old) and the second, the control group, consisted of 917 women aged between 20 and 40 years old.

RESULTS

A high percentage of pregnancies (22.2%) and voluntary abortions (41.6%) was observed in teenagers, associated with different sexual behaviours. The age of sexual intercourse was below 15 in 44.4% of adolescents (vs 7.7% of controls), whereas 61.1% had more than one sexual partner and 20.4% had changed partners in the last 6 months (vs 7.4%). 50% of teenagers did not use any method of contraception (vs 44.2%) and barrier methods were only used by 20.4% (vs 18.4%).

CONCLUSIONS

Our study confirms the existence of a high-risk behavioural pattern in the adolescent population and draws attention yet again to the need for a serious programme of prevention and sexual education which will allow adolescents to experience the discovery of their own sexuality with greater awareness and safety.

Evaluation of the Abbott CELL-DYN 4000 hematology analyzer

A new generation hematology analyzer, Abbott CELL-DYN 4000 (CD 4000), capable of providing 26 parameters, including fully automated reticulocyte, nucleated RBC, blast, band, and immature granulocyte, and variant lymphocyte counts, was evaluated by using the National Committee for Clinical Laboratory Standards H20-A protocol and compared with the Bayer-Technicon H-2 analyzer, which is used routinely in our laboratory. A lipid interference experiment and a sample aging study also were performed. Linearity, carryover, and precision were within the limits established by the manufacturer, and satisfactory agreement was found with the H-2 analyzer. The evaluation of leukocyte differential counts indicated an excellent correlation with the manual reference method for neutrophils and lymphocytes, a good correlation for monocytes and eosinophils, and a poor correlation for basophils in samples with low counts; for basophil counts of 2% or higher, we found an improvement of the correlation coefficient. In the lipid interference experiment, only hemoglobin determination was influenced significantly on the CD 4000, but by using a new Abbott hemoglobin reagent, the interference was eliminated. The CBC and differential counts were stable and reportable up to at least 24 hours. Intrasample viability information on leukocytes provided a quality check on each individual specimen.

[Pregnancy cholestasis. Clinical aspects and neonatal outcome]

AIM

Gravidic cholestasis is a syndrome that is usually manifested during the third trimester of pregnancy and regresses in puerperium. It is characterized by the onset of itch, with or without associated jaundice and alterations of hepatic functional parameters. Its incidence varies according to geographical area.

METHODS

A retrospective analysis was made regarding the frequency of this pathology in pregnant patients attending the Gynecology and Obstetrics Clinic of Trieste from 1-1-1980 to 31-7-1997. The epidemiological and clinical characteristics were studied relating to the course of pregnancy and neonatal outcome. Patients were identified on the basis of diagnosis on admittance and anamnestic and laboratory data, generalised itch and increased transaminase, biliary salts and alkaline phosphatase. Patients suffering form active-phase viral hepatitis were excluded, as were those in whom symptoms appeared after the start of alpha methyldopa administration.

RESULTS

The frequency of gravidic cholestasis in this series was 0.36%. No significant differences were recorded in terms of age, parity and weight increase in these patients compared to the general population of pregnant women. Birth was spontaneous in 66% and by cesarean section in 34%. The frequency of premature births was 12%. The Apgar score at 5 min was satisfactory in all neonates.

CONCLUSIONS

Careful monitoring of pregnancy associated with suitable obstetric care enabled a zero rate neonatal and maternal mortality to be achieved.

Essential mixed type II cryoglobulinemia in a HCV positive pregnant woman: case report

Cryoglobulins are a group of proteins with the common property of precipitating from cooled serum. Cooled cryoglobulinemia is a classic disease caused by immune complexes which subside on vessel walls and produce a clinical picture represented by recurrent purpura, asthenia, arthralgias, Raynaud's phenomenon, glomerulonephritis and sensorimotor neuropathy. The authors describe a case of a patient C.M., 37 years old, with cryoglobulinemia, chronic hepatitis C and gravidic cholestasis at 28 weeks' gestation. The clinical picture worsened with the appearance of mild hypertension with proteinuria and hypochromic anaemia. At 31 weeks' the arthralgic symptomatology and pruritus revealed degeneration with an alteration of glycemic profile values and treatment with rapid human insuline was started. The cardiotocography began to be pathologic and a cesarean section was performed; the newborn weighted 1570 g. Cooled cryoglobulinemia is a pathology which worsens in a gravidic state and can impair the outcome of pregnancy.

[Percutaneous mechanical revascularization of chronic iliac artery occlusion with "first intention" stent placement]

INTRODUCTION

Percutaneous treatment of chronic iliac artery occlusion has not yet gained complete acceptance as the method of choice. The reason of this widespread skepticism are the poor results achieved with angioplasty and/or lysis therapy. The introduction of stents seems to open new perspectives to percutaneous treatment and the latest follow-up studies report encouraging results.

MATERIAL AND METHODS

We report our personal experience in percutaneous mechanical revascularization of chronic iliac occlusion with primary stent placement in 29 patients with 2 years' maximum follow-up. Clinically the patients had at least 3 months' claudication and were in Fontaine stages II to IV. The occlusion was passed mechanically using a hydrophilic guide wire, through the contralateral access in 19 cases and ipsilaterally in 10. The stents were primarily implanted in the last 12 patients; in the first 15 patients, after dilatation with undersized balloons, 25 Wallstent and 12 Palmaz stents were implanted. Each patient underwent color Doppler follow-up for 3-24 months. Nine patients underwent angiography too, after one year.

RESULTS

The mechanical passage of the guide-wire through the occluded segment was successful in 27 of 29 (93.1%) patients referred for percutaneous revascularization of a chronic occlusion of the iliac artery. The stent was placed and immediate patency was achieved in 100% of these 27 patients. Clinical improvement was of two stages in 24 patients and of one stage in 3 patients. The follow-up showed neither reocclusions nor critical stenoses of the restored iliac segment. Five embolic complications (5%) occurred after angioplasty, all of them treated percutaneously; surgery was never necessary.

DISCUSSION AND CONCLUSIONS

The follow-up studies published in the literature in the last few years and our personal experience encourage the percutaneous treatment of chronic iliac artery occlusions. Percutaneous mechanical revascularization with primary stent positioning can be proposed because it is a reliable and efficacious tool, particularly in young patients in whom a surgical aortoiliac or aortofemoral bypass might injure the pudendal plexis and cause sexual disturbances.

[Insulinemic response to oral glucose loading tests in screening for diabetes in pregnancy]

BACKGROUND AND AIMS

Given that an increased peripheral insensitivity to insulin represents the primum movens of gestational diabetes, it is reasonable to suppose that the determination and evaluation of the insulinemic response to an oral glucose loading test may represent a simple, effective and low cost screenign test. A method was devised which consisted in performing two assays of insulin and glycemia in venous blood; the first while fasting, the second one hour after the ingestion per os of 50 g glucose.

METHODS

A group of 79 pregnant women, aged between 20 and 41 years old (mean age 30.5), was tested in around the 23rd week of gestation. All women were attending the Obstetric and Gynecological Clinic at Trieste University.

RESULTS

Based on the results obtained, insulinemic parameters appear to be significantly correlated with data for the short glycemic curve according to O'Sullivan-Mahan.

CONCLUSIONS

This study appears to confirm the need to include insulinemic tests as part of the new and more efficacious glucose tolerance tests and to perform prospective studies in order to identify the most reliable screening method in terms of sensitivity and specificity, also in relation to the cost-benefit ratio.

Eligibility criteria for labor induction with prostaglandins

Particular conditions exist at the end of some pregnancies which cause an increase in maternal and fetal risk. A valid alternative for these pregnancies is represented by the administration of prostaglandins, in order to obtain labor induction. The goal of our study was to define the eligibility criteria and the epidemiological characteristics that correlate most with a favorable obstetrical outcome. The study was conducted on 133 informed, consenting patients subjected to labor-induced delivery with prostaglandins E2. The mode of delivery in relationship to parity demonstrated that the pluriparous patients had fewer difficulties in labor and in its induction: of the 43 pluriparous cases, none had a cesarean section for failed induction and 95.3% delivered vaginally. One hundred percent of the patients with a Bishop score of more than 4 went into labor, as opposed to 81% of the patients with a score of less than 4. Therefore, taking into consideration the cost of the method, we retain that choosing an active position is valid, respecting the eligibility criteria for the induction of labor described above.

Monoethylglycinexylidide production as a measure in predicting hepatic histology

To clarify whether monoethylglycinexylidide (MEGX) production can be useful in predicting the severity of chronic liver disease, 51 subjects were enrolled in this study: 13 mild-moderate CAH (group A), 9 severe CAH (group B), 29 cirrhosis, 18 compensated and 11 decompensated disease (group C). The patients were injected with a 1 mg/Kg lidocaine bolus i.v. and serum-sampled for MEGX values (time 15, 30 and 60 minutes), determined by TDX-immunoassay. MEGX formation was significantly different (Mann-Whitney U test) in the three groups at each time interval, especially at 30 min: group A = 70.5 +/- 9.9 ng/ml (mean +/- SD); group B = 49.7 +/- 7.2; group C = 37.2 +/- 19.5 (in A vs B, p = 0.0003; in A vs C, p < 0.0001; in B vs C, p = 0.0237). The difference between compensated and decompensated cirrhosis was always significant (p = 0.0099, 0.0005, 0.0113 respectively) but between severe CAH and compensated cirrhosis it was marginal only at 15min (p = 0.0763) and absent at 30 and 60min. At 30min MEGX values > 60 suggest mild-moderate CAH, < 40 cirrhosis, < 30 decompensated cirrhosis, between 40 and 60 severe CAH or compensated cirrhosis. We are of the opinion that the MEGX test could be utilized to predict hepatic histology.

Determination of the kinetics of Na+/H+ exchange in platelets using the Coulter S-plus cell counter

Cell swelling, as measured by electronic cell sizing, is a good indicator of the Na+/H+ exchange activation. In this study the kinetic properties of the Na+/H+ exchanger were determined with the aid of the Coulter S-Plus VI D haematological cell counter. Cell swelling was measured in platelets suspended in Na-propionate medium. The rapid entry and intracellular dissociation of propionic acid induces activation of the exchanger, and in turn the uptake of water by osmosis. The fractional volume increase measured by the Coulter S-Plus was dependent on the external Na-concentration, with Km = 86 mmol/l. Saturation was reached at a propionate concentration of 140 mmol/l. Inhibition by amiloride was dose-dependent with Ki = 24 mumol/l. The activity of the exchanger was not modified by ouabain. These data are generally consistent with those published in previous reports, and indicate that automated haematological analysers are appropriate for the study of this aspect of platelet function.

Evidence of a cold immunoglobulin M autoantibody against 78-kD platelet glycoprotein in a case of EDTA-dependent pseudothrombocytopenia

Pseudothrombocytopenia is a phenomenon in which the electronic count shows spuriously low platelet counts in subjects with normal platelet levels. The mechanism of anticoagulant-dependent pseudothrombocytopenia appears to involve cold reactive agglutinins against platelet antigens. The authors report a case of EDTA-dependent pseudothrombocytopenia with evidence of a cold immunoglobulin M antibody against 78-kD platelet membrane glycoprotein (GP). Cell counts were performed by Coulter Counter S-Plus VI (Coulter, Hialeah, FL) in the following anticoagulants: EDTA, Na-citrate, and citrate-theophylline-adenosine-dipyridamole. Anti-platelet antibodies and platelet membrane GP antigens were assayed by an immunofluorescence technique as described by Van dem Borne in 1978. An immunoglobulin M/lambda anti-platelet antibody was found to react in serum as well as in plasma EDTA at room temperature, but not at 37 degrees C. This antibody appeared to be directed against GP78 membrane antigen because this antigen was not detectable by immunofluorescence in platelets collected in EDTA and Na-citrate anticoagulant, whereas a fluorescence signal was revealed in platelets collected in citrate-theophylline-adenosine-dipyridamole. This evidence was confirmed by platelet clumping inhibition tests in which target platelets were pretreated with anti-GP monoclonal antibodies. Clumping in the presence of pseudothrombocytopenia serum was inhibited by anti-GP78kD and anti-GPIIb/IIIa but not by anti-Ib. In this case, GP78 appears to be involved in platelet clumping, together with IIb/IIIa complex. The partial inhibition of the phenomenon observed in citrate-theophylline-adenosine-dipyridamole is probably related to a lower expression of the membrane antigens in platelets collected in this anticoagulant.

Characterization of Hemoglobin Lepore Variants by Advanced Mass-Spectrometric Procedures

We describe an analytical protocol for characterizing the molecular structure of hemoglobin (Hb) Lepore variants by using two different mass-spectrometric approaches. The first method consists of direct examination of the chromatographically separated hybrid globins by electro-spray mass spectrometry; the variant Lepore globin is identified through the accurate determination of its molecular mass. Alternatively, the anomalous globins are digested with trypsin and their structures are determined by fast atom bombardment mass-spectrometric analysis of the peptide mixture. The application of this procedure to the identification of Hb Lepore Boston and Hb Lepore Baltimore is described.

Characterization of hemoglobin lepore variants by advanced mass-spectrometric procedures

We describe an analytical protocol for characterizing the molecular structure of hemoglobin (Hb) Lepore variants by using two different mass-spectrometric approaches. The first method consists of direct examination of the chromatographically separated hybrid globins by electro-spray mass spectrometry; the variant Lepore globin is identified through the accurate determination of its molecular mass. Alternatively, the anomalous globins are digested with trypsin and their structures are determined by fast atom bombardment mass-spectrometric analysis of the peptide mixture. The application of this procedure to the identification of Hb Lepore Boston and Hb Lepore Baltimore is described.

[Evaluation of the Coulter T-660 hematologic analyzer compared with the Hemalog 8/90]

The authors evaluated technical performance of two automated haematological counters, the Coulter T-660 in comparison to Hemalog 8/90. Both systems showed a good correlation and a good precision. The Coulter T-660 revealed to be a high standard analyzer, that can adequately support more complex haematological analyzers in laboratory routine.