Genetic analysis of osteogenesis imperfecta in a large Brazilian cohort

INTRODUCTION

Osteogenesis imperfecta (OI) is a genetically and clinically heterogeneous disorder caused by disruption of type I collagen synthesis. Previous Brazilian molecular OI studies have been restricted to case reports or small cohorts. The Brazilian OI Network (BOIN) is a multicenter study collecting clinical OI treatment data from five reference centers in three regions of Brazil.

OBJECTIVE

To describe the molecular analysis of a large cohort of OI registered at BOIN.

METHODS

Targeted next-generation sequencing (NGS) was performed at a centralized laboratory with the Ion Torrent platform, covering 99.6 % of the coding regions of 18 OI-associated genes. Clinical information was obtained from a clinical database.

RESULTS

We included 156 subjects in the molecular analyses. Variants were detected in 121 subjects: 65 (53.7 %) in COL1A1, 42 (34.7 %) in COL1A2, 2 (1.7 %) in IFITM5, one (0.8 %) in CRTAP, three (2.5 %) in P3H1, two (1.7 %) in PPIB, four (3.3 %) FKBP10, one (0.8 %) in SERPINH1, and one (0.8 %) in TMEM38B. Ninety-one distinct variants were identified, of which 26 were novel. Of the 107 variants identified in COL1A1 and COL1A2, 24.5 % cause mild OI, while the remaining 75.5 % cause moderate, severe, or lethal OI, of which 49.3 % are glycine to serine substitutions. A single variant in FKBP10 (c.179A>C; p.Gln60Pro) was found in three unrelated and non-consanguineous participants living in the same geographic area in Northeast Brazil, suggesting a possible founder effect.

CONCLUSION

Consistent with the literature, 88.4 % of the subjects had a variant in the COL1A1 and COL1A2 genes, with 10 % inherited in an autosomal recessive manner. Notably, one variant in FKBP10 with a potential founder effect requires further investigation. Data from this large cohort improves our understanding of genotype-phenotype correlations for OI in Brazil.

Effectiveness of standard cervical physiotherapy plus diaphragm manual therapy on pain in patients with chronic neck pain: A randomized controlled trial

BACKGROUND

Literature concerning the effect of diaphragm treatment to reduce neck pain symptoms is scarce. Aim of this trial was to investigate the effects of diaphragm manual therapy associated with standard physiotherapy treatment on pain in patients with Chronic Neck Pain (CNP).

METHODS

In a private practice clinic, subjects with CNP were randomly assigned to receive three 30-min treatment sessions of standard cervical physiotherapy and Diaphragm Manual Therapy (DMT) or Sham Diaphragm Technique (SDT). Participants and assessors were blinded to the assignment. Primary outcome was pain, secondary outcomes were cervical active range of motion, pain pressure threshold, disability and quality of life measured at baseline, before and after each session, at 3 and 6-months. Adverse events were monitored. A non-parametric multivariate approach (combined permutation test) was applied to assess the effect of the treatment on all the outcomes. An intention to treat analysis was performed.

RESULTS

Forty patients were randomly allocated to DMT and SDT groups. Combined permutation test showed a significant higher improvement in DMT group compared to SDT group (p-value = 0.0002). The between-group comparisons on single outcomes showed a statistically significant improvement only for pain pressure threshold on upper trapezius (adjusted p-value = 0.029). No adverse events related to the intervention were registered.

CONCLUSIONS

In patients with CNP, addition of diaphragm manual techniques to standard cervical treatment seems to give a better global outcome, but this improvement is of unclear clinical relevance; the primary outcome seems not to have a role. Further studies are needed to confirm and clarify these results.

TRIAL REGISTRATION

Release Date: July 18, 2017 Registered in ClinicalTrial.gov database ID: NCT03223285A.

Rare autosomal trisomies: comparison of detection through cell-free DNA analysis and direct chromosome preparation of chorionic villus samples

OBJECTIVE

Direct chromosome preparations of chorionic villus samples (CVS) and cell-free DNA (cfDNA) testing both involve analysis of the trophoblastic cell lineage. The aim of this study was to compare the spectrum of rare autosomal trisomies (RATs) detected by these two approaches and assess the available information on their clinical significance.

METHODS

Data from 10 reports on genome-wide cfDNA testing were pooled to determine which chromosomes were most frequently involved in RAT-positive cases, and pregnancy outcome information was reviewed. CVS information was obtained from an updated database of 76 102 consecutive CVS analyses performed over a period of 18 years at TOMA laboratory, in which trophoblastic and mesenchymal layers were analyzed and amniotic fluid cell analysis was recommended for RAT-positive cases. Chromosomes involved and presence of confined placental mosaicism, true fetal mosaicism and uniparental disomy (UPD) for imprinted chromosomes were assessed. Also evaluated were the frequency and types of RATs in products of conception.

RESULTS

RATs were present in 634 of 196 662 (0.32%) cfDNA samples and 237 of 57 539 (0.41%) CVS trophoblast samples (P < 0.01). The frequency of RATs varied over 8-fold between the cfDNA reports. Confirmation of abnormality through amniocentesis was more likely when RATs were ascertained through cfDNA (14 of 151; 9.3%) than through CVS trophoblasts (seven of 237; 3.0%) (P < 0.01). In cfDNA-ascertained cases, trisomies 15, 16 and 22, which are associated with fetal loss, were identified proportionately more often. Of 151 cases with RAT identified by cfDNA and outcome information available, 41.1% resulted in normal live birth; 27.2% in fetal loss; 7.3% had phenotypic abnormality detected through ultrasound or other follow-up evaluation; 2.0% had a clinically significant UPD; and 14.6% had fetal growth restriction or low birth weight. All autosomes were involved in trisomies in products of conception; the most common RATs detected were trisomies 16, 22 and 15 with a frequency of > 9% each.

CONCLUSIONS

Although there are strong parallels between RATs ascertained through cfDNA analysis and direct chromosome preparation of CVS, caution is needed in applying conclusions from CVS analysis to cfDNA testing, and vice versa. RATs identified through genome-wide cfDNA tests have uncertain risks for fetal loss, growth restriction or fetal abnormality. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

Arthrodesis of the ankle joint in septic osteoarthritis: six years long term outcomes in authors' personal experience

OBJECTIVE

Our goal was to evaluate the long-term clinical outcome of ankle arthrodesis, obtained by an extramedullary internal fixation with or without bone-grafting in the treatment of ankle' septic arthritis.

PATIENTS AND METHODS

All patients treated with arthrodesis by extramedullary internal fixation for septic arthritis of the ankle joint between January 2011 and December 2016 in the same hospital were included in our retrospective study. Patients were followed-up for a minimum of two years. To evaluate the quality of life, each patient filled in a short form of the physical and mental health summary scale and a visual analogue scale for pain. For the functional evaluation, the American Orthophaedic Foot and Ankle Society Score was used. Demographics and clinical data, including perioperative and postoperative complications, were evaluated.

RESULTS

From January 2011 to December 2016, we performed 57 arthrodeses of the ankle joint with cannulated screws in 52 patients. Mean age was 52 years old. 48 patients (92%) had post-traumatic septic arthritis. The most frequently isolated pathogens were Staphylococcus aureus and Pseudomonas aeruginosa. 48% of patients reported a postoperative complication after three months; the most commonly reported complications were weight bearing ankle-foot pain (27%) and surgical wound dehiscence (12.25%). Nonunion was reported only in 8.75% of cases.

CONCLUSIONS

Ankle arthrodesis could allow painless gait, improving patients life quality, even after long-term follow-up, and is, therefore, a solution to be considered in patients affected by septic arthritis.

A pharmacogenetic-driven approach for controlled ovarian hyperstimulation by FSH treatment

AIM

The aim of this study was to develop a pharmacogenetic- (PGx) driven approach for a controlled ovarian hyperstimulation (COH) treatment protocol used for in vitro fertilization procedures. The enrolled patients were genotyped for a single nucleotide polymorphism (SNP) N680S, within the FSHR.

METHODS

Seventy-eight women, who had previously received at least two COH cycles without positive fertilization with FSH and AMH values <10 mUI/mL and >0.3 ng/mL respectively were enrolled. They were genotyped for N680S and then categorized in high (HR), intermediate (IR), and poor responders (PR). Each subgroup received a tailored FSH treatment of 100, 225, and 400 UI/mL, respectively. The response was evaluated considering differences with previous COH cycle in terms of number of follicles (FR), oocytes (OR), and embryos produced (EMB).

RESULTS

With regards to the endpoint considered comparing the non-PGx with the PGx approach, for what regards the FR a statistically significant increase of their numbers was observed with the PGx-tailored approach (HR P<0.0001; IR P=0.00892; PR P=0.0032). Similar statistical significant results were also achieved for OR but only for HR (P<0.0001) and IR (P=0.00169). Last but not least for the EMB (HR P<0.001; IR P=0.00670 and PR P<0.0001) all the different genotype considered achieved a statistical significance.

CONCLUSION

This study, although with a limited number of enrolled patients, showed that a FSH treatment with a PGx-driven approach might have the potential to improve COH clinical outcome.

Microarray application in prenatal diagnosis: a position statement from the cytogenetics working group of the Italian Society of Human Genetics (SIGU), November 2011

A precise guideline establishing chromosomal microarray analysis (CMA) applications and platforms in the prenatal setting does not exist. The controversial question is whether CMA technologies can or should soon replace standard karyotyping in prenatal diagnostic practice. A review of the recent literature and survey of the knowledge and experience of all members of the Italian Society of Human Genetics (SIGU) Committee were carried out in order to propose recommendations for the use of CMA in prenatal testing. The analysis of datasets reported in the medical literature showed a considerable 6.4% incidence of pathogenic copy number variations (CNVs) in the group of pregnancies with sonographically detected fetal abnormalities and normal karyotype. The reported CNVs are likely to have a relevant role in terms of nosology for the fetus and in the assessment of reproductive risk for the couple. Estimation of the frequency of copy number variations of uncertain significance (VOUS) varied depending on the different CMA platforms used, ranging from 0-4%, obtained using targeted arrays, to 9-12%, obtained using high-resolution whole genome single nucleotide polymorphism (SNP) arrays. CMA analysis can be considered a second-tier diagnostic test to be used after standard karyotyping in selected groups of pregnancies, namely those with single (apparently isolated) or multiple ultrasound fetal abnormalities, those with chromosomal rearrangements, even if apparently balanced, and those with supernumerary marker chromosomes.

Chromosome 11 segmental paternal isodisomy in amniocytes from two fetuses with omphalocoele: new highlights on phenotype-genotype correlations in Beckwith-Wiedemann syndrome

BACKGROUND

The phenotypic variability in Beckwith-Wiedemann syndrome (BWS) reflects the genetic heterogeneity of the mechanism which by default leads to the deregulation of genes located at 11p15.5. Genotype-phenotype correlation studies have demonstrated an association between omphalocoele and CDKN1C/p57 mutations or hypermethylation. Paternal uniparental disomy 11 (pUPD11) has been described only in the mosaic condition with both uniparental and biparental cell lines, and no association with omphalocoele has been pointed out.

METHODS

Two cases are presented here, in which a paternal segmental UPD11 was detected by molecular investigation of amniotic fluid cell cultures after the presence of apparently isolated omphalocoele was revealed in the fetuses by ultrasound scan. Further studies were performed on additional autoptic feto-placental tissues to characterise the distribution of the uniparental cell line and to unmask any biparental lineage in order to document in more detail the as yet unreported association between omphalocoele and pUPD11.

RESULTS

Results on the UPD distribution profile showed that the abdominal organs have a predominant uniparental constitution. This condition could mimic the effect of CDKN1C/p57 inactivation, causing the omphalocoele.

CONCLUSION

New genotype-phenotype correlations emerge from the investigated cases, suggesting that molecular analysis be extended to all cases with fetal omphalocoele in order to establish the incidence of pUPD11 in complete BWS and in monosymptomatic/mild forms.

Fetal and placental chromosomal mosaicism revealed by QF-PCR in severe IUGR pregnancies

A number of genetic and environmental factors are taken into account as responsible for intrauterine growth restriction (IUGR); nevertheless, the relevance of genetic alteration in IUGR aetiology remains to be determined. The aim of this study was to investigate using a combined cytogenetic-molecular approach, improved by a new application of QF-PCR method, the presence of mosaic chromosomal changes in fetal/placental samples from 12 pregnancies with unexplained severe IUGR. This multiple approach allowed us to reveal and quantify subtle chromosomal mosaicisms with less than 5% of trisomic cells even in cases in which cytogenetic and FISH analyses failed to reveal them. These are three pregnancies with a mosaic trisomy for chromosomes 7, 2 and 14; the former case presented matUPD7 and was previously described in this journal (Placenta 22 (2001) 813) in association with pre- and postnatal growth restriction. It is intriguing that chromosomes 7, 2 and 14 are known or suspected to harbour imprinted genes, so that an unbalanced gene dosage in a subset of cells during embryonic development could lead to an early impairment of placental function. Our findings indicate that extensive molecular and cytogenetic studies of IUGR fetal and placental tissues are necessary to reveal at least part of the heterogeneous genetic lesions implicated in IUGR phenotypes.

Genetic characterization of the three medicinal Echinacea species using RAPD analysis

The three medicinal species of the Echinacea genus, E. angustifolia DC., E. pallida (Nutt.) Nutt. and E. purpurea (L.) Moench were distinguished using the RAPD (random amplified polymorphic DNA) technique. Species-specific markers were identified from amplicons obtained with four of the twenty 10-mer primers contained in the Operon RAPD kit A. In particular, one marker was identified for E. angustifolia (OPA 20, 1800 pb) and E. pallida (OPA 10, 600 pb) and three markers for E. purpurea (OPA 11 : 1250 pb; OPA 17 : 750, 1800 pb). Genetic distance analysis indicated a high degree of difference among the three species with a relative lower difference between E. angustifolia and E. pallida.

[Growth rate of abdominal aortic aneurysms. Ultrasounds study and clinical outcome]

BACKGROUND

The standard treatment for abdominal aortic aneurysms (AAA) >55 mm is actually represented by surgical repair mainly or by endovascular repair, in selected cases; conversely the debate is still open for those ranging 40-55 mm. These last and smaller aneurysms are usually followed-up by ultrasounds (US), in order to detect too fast expansions and to prevent sudden ruptures. Aim of this study is to present the results of the US follow-up of a series of asymptomatic AAAs and the correlation between expansion rate and associated risk factors.

METHODS

All patients evaluated for an AAA between March 1991 and December 2000 were included and, according to the maximum diameters of the infrarenal aorta, were divided into 3 groups: A (26-29 mm), B (30-39 mm) and C (>39 mm). Groups A and B underwent US follow up at 6-month intervals, while group C underwent a complete preoperative evaluation.

RESULTS

The mean follow up was 36+/-24 months for the entire series (225 AAA); the mean expansion rate was 1 mm/year for group A, <1.5 mm/year for group B for the first 5 years with a sharp increase (5 mm/year) in the following 2 years and 3 mm/year for group C up to 5 years. Among the associated risk factors, hypertension and smoking have confirmed their main role, independent from the initial diameter (p<0.01). Eight ruptures (3.8%) occurred in patients unsuitable for surgery or who refused it and in 7 cases they were lethal. The range between diagnosis and death (19-61 months) and the maximum size (38-93 mm) were absolutely unpredictable. The remaining 40 deaths were related to vascular diseases (MI and stroke 29.8%) or concurrent neoplasms (29.8%) mainly. The surgical treatment was carried out as elective repair on 45 patients (mortality rate 2.2%) and in emergency in 2 cases, both dead, with a mean interval from diagnosis to surgery of 28+/-17 months.

CONCLUSIONS

Our results agree with the literature data concerning the dilatative trend and the risk factors and, according to these, elective repair in patients with AAA ranging 45-55 mm should be considered.

Loss of heterozygosity of the NOS3 dinucleotide repeat marker in atherosclerotic plaques of human carotid arteries

We have investigated 28 atherosclerotic plaques of human carotid arteries with a panel of 39 microsatellite markers for the presence of LOH. The objective of this research was to verify if LOH, described in association with tumorigenic process, could be involved also in benign fibroproliferative disease. Seventy percent of samples demonstrated allelic imbalance: 50% of cases showed LOH at a minimum of one locus, 3.5% at a minimum of two loci and 14.3% at three or more loci. The percentages of LOH ranged between 3.8 and 14.3% and the highest involved polymorphic marker is the NOS3 internal dinucleotide repeat. Our results indicate that, like tumorigenesis, the atherogenic process could also involve LOH mechanism. Furthermore, the finding regarding the NOS3 internal polymorphism suggests a possible role of the gene as cofactor in formation of the atheromas.

Post-zygotic origin of complete maternal chromosome 7 isodisomy and consequent loss of placental PEG1/MEST expression

Maternal UPD of chromosome 7 is associated with pre- and postnatal growth retardation (IUGR, PNGR) and Silver-Russell syndrome (SRS [MIM 180860]). We report a case of IUGR in a newborn with SRS stigmata. Using combined haplotyping and cytogenetic-FISH studies we characterized the lymphocytes, umbilical cord and four placental cotyledons. The results are consistent with complete maternal isodisomy 7 and trisomy 7 mosaicism of post-zygotic origin. The trisomic cell line was prevalent in trophoblast cells from two placental cotyledons. Trisomy 7 of post-zygotic origin is a frequent finding, but maternal isodisomy 7, due to trisomic rescue has never been reported. PEG1/MEST expression was evaluated on placenta cDNA and a specific transcript was revealed only in the cotyledons with a high percentage of trisomic cells and the presence of the paternal chromosome 7 contribution, but not in the placental biopsies with maternal isodisomy 7. The histological features of the four placental fragments revealed that isodisomy 7 correlates with a pattern of cotyledonary hyper-ramification due to an increase of the branching angiogenesis, which could be the result of a defect of angiogenesis caused by the absence of PEG1 product. The severe hypo-ramification of the two cotyledons, showing trisomy 7 mosaicism, may be due to the triplicate dosage of genes on chromosome 7. The delayed fetal growth could be the phenotypic effect of the imbalance between imprinted and non-imprinted genes on chromosome 7 in the fetus or the result of abnormal placental function during pregnancy.

External carotid artery shunting during carotid endarterectomy: an alternative for cerebral protection?

OBJECTIVES

to assess the application of external carotid artery (ECA) shunting in cerebral protection during carotid endarterectomy (CEA).

DESIGN

prospective study.

MATERIALS AND METHODS

the study comprised 137 consecutive patients who underwent CEA under locoregional anaesthesia. Transcranial Doppler was used to monitor the mean velocity of the middle cerebral artery (mv-MCA): (1) before carotid clamping; (2) after clamping both the common and external carotid arteries; (3) after clamping the internal carotid artery alone ("ECA test"). The decision to shunt was based on the occurrence of neurological deficit during carotid clamping. If the ECA test revealed mv-MCA approaching the pre-clamping values ECA shunting was used, whereas the remaining patients in need of a shunt had a standard internal carotid artery (ICA) shunt.

RESULTS

shunting was necessary in 12/137 cases (9%). The ECA test indicated that in four cases - 3% of the whole series or 33% of the shunted cases. In these four patients ECA shunting reversed the neurological deficit, and CEA was successfully performed without any complications.

CONCLUSIONS

ECA shunting could be considered as an alternative to standard ICA shunting. Suitable cases can be identified on the basis of the ECA test.

Blood fetal microchimerism in primary biliary cirrhosis

The autoimmune nature of primary biliary cirrhosis (PBC) is well established. We tested the hypothesis that fetal microchimerism indicated by the persistence of circulating fetal cells in women years after pregnancy might contribute to the aetiopathogenesis of PBC through a graft-versus-host-like response. We extracted DNA from the peripheral blood cells of 36 women carefully selected from 173 consecutive PBC patients, who were matched with 36 healthy women by age, age of last son, and number of children. Both patients and controls had to have male offspring, and no history of miscarriages or blood transfusions; they could not be twins. We tested all of the samples for the presence of two specific Y-chromosome sequences (SY154 and SRY) by amplifying DNA in a nested polymerase chain reaction. Y-chromosome-specific DNA was detected in the peripheral blood cell DNA of 13 (36%) of the 36 women with PBC and in 11 (31%) of the 36 healthy controls. The two groups of PBC patients with and without male DNA sequences were similar in terms of their clinical, biochemical, and serological features. Y-chromosome sequences were found in three of the four PBC women with associated systemic sclerosis. All of the 24 Y-positive samples contained SY154 sequences, but only three PBC patients and six controls showed the presence of both SY154 and SRY sequences. This discrepancy may suggest that not only fetal cells but also fragments of fetal DNA are present in maternal circulation. Overall, our data do not support the hypothesis that fetal microchimerism plays a significant role in the onset or progression of PBC.

A novel hemoglobin-adenosine-glutathione based blood substitute: evaluation of its effects on human blood ex vivo

Chemically modified hemoglobin (Hb) solutions are under current investigation as potential red cell substitutes. Researchers at Texas Tech University have developed a novel free Hb based blood substitute product. This blood substitute is composed of purified bovine Hb cross-linked intramolecularly with o-adenosine-5'-triphosphate and intermolecularly with o-adenosine, and conjugated with reduced glutathione (GSH). In this study, we compared the effects of our novel blood substitute and unmodified (U) Hb, by using allogenic plasma as the control, on human blood components: red blood cells (RBCs), platelets, monocytes (Mo), and low-density lipoproteins (LDLs). The pro-oxidant potential of both Hb solutions on RBCs was examined by the measurement of osmotic and mechanical fragility, conjugated dienes (CD), lipid hydroperoxides (LOOH), thiobarbituric acid reactants (TBAR-S), isoprostanes (8-iso PGF2alpha) and intracellular GSH. The oxidative modification of LDLs was assessed by CD, LOOH, and TBAR-S, and the degree of apolipoprotein (apo) B cross-linking. The effects of Hb on platelets have been studied by monitoring their responses to the aggregation agonists: collagen, ADP, epinephrine, and arachidonic acid. Monocytes were cultured with Hb solutions or plasma and tested for TNF-alpha and IL-1beta release, then examined by electron microscopy. Results indicate that native UHb initiates oxidative stress of many blood components and aggravates inflammatory responses of Mo. It also caused an increase in RBC osmotic and mechanical fragility (p < 0.001). While the level of GSH was slightly changed, the lipid peroxidation of RBC increased (p < 0.001). UHb was found to be a stimulator of 8-iso PGF2alpha synthesis, a potent modulator of LDLs, and an effective potentiator of agonist induced platelet aggregation. Contrarily, our novel blood substitute did not seem to induce oxidative stress nor to increase Mo inflammatory reactions. The osmotic and mechanical fragility of RBCs was similar to that of the control. Such modified Hb failed to alter LDLs, increase the production of 8-iso PGF2alpha, but markedly inhibited platelet aggregation. The effect of this novel blood substitute can be linked with the cytoprotective and anti-inflammatory properties of adenosine, which is used as a cross-linker and surface modifier, and a modification procedure that lowers the hemoglobin pro-oxidant potential.

Differential device performances for hepatic arterial chemotherapy: a technical report on totally implantable pumps and ports for both continuous and bolus infusion

Performances of totally implantable infusion systems were analyzed in patients with colorectal liver metastases undergoing intra-arterial treatment. It consisted of 14-day continuous infusion of 5-fluor-2'deoxyuridine with pumps (pump14, 44 patients) or ports fed by external pumps (port14, 34 patients), or bolus infusion of cisplatin (port21, 57 patients) or epirubicin (port7, 22 patients) every 3rd week and weekly, respectively. Toxicity and disease progression were the most common causes of treatment interruption. System failure occurred in 2 pump14, 9 port14, 6 port21 and 2 port7 cases. Pocket problems were most frequent in the pump14 group (30%), whereas catheter- and infusion-related problems were mostly observed in the port14 group (109%). The devices were still functional after 12 months in 92% of pump14, 24% of port14, 65% of port21 and in 78% of port7 patients. Although implantable ports allow adequate infusion periods, in most cases they appear especially suitable for bolus infusions.

Losses of heterozygosity in endometrial adenocarcinomas: positive correlations with histopathological parameters

We analyzed 37 samples of endometrial adenocarcinoma for loss of heterozygosity (LOH) by using a panel of 44 microsatellites located in 29 chromosomal regions. The aim of our study was to investigate the existence of a possible preferential involvement of some tumor suppressor genes in endometrial carcinogenesis. The analysis was performed on tumoral tissue and on a corresponding normal tissue by the use of polymerase chain reaction (PCR) and the comparison of the amplified alleles. We observed significative LOH (>20%) in the chromosomal regions of 2q14 (33.33%), 7q35 (24.00%), 10q22.1 (37. 50%), 11q13-q14 (44.12%), 15q26 (40.63%), 17p13 (25.71%), and 17q21. 3 (37.04%). We defined a 1-cM minimal common deletion in 11q13-q14 between D11S911 and D11S937 markers. A statistical analysis revealed a positive correlation between LOH of 11q13-q14 and clinicopathological data.

Losses of heterozygosity in oral and oropharyngeal epithelial carcinomas

We analyzed 25 oral and oropharyngeal epithelial carcinomas for loss of heterozygosity (LOH) and microsatellite instability by using 55 oligonucleotide repeat markers located in 45 chromosomal regions. The aim was to identify which chromosomal regions and tumor-suppressor genes (TSGs) are preferentially lost in these tumors and to relate LOH at specific loci to clinicopathologic data. The analysis was performed on tumor tissue and on a corresponding normal tissue (blood lymphocytes) with the use of the polymerase chain reaction technique followed by microsatellite allele separation with denaturing gel electrophoresis. Thirty-two of 45 chromosomal regions demonstrated a significant (>/=20%) incidence of LOH. An allelic loss of >/=50% was found in 9p21 (77.8%), 8p22-23 (70%), 3p12 (61.5%), 1p36.1 and 12q22 (60%), 3q28 (57.1%), 5q23.3 (54.5%), 3p25-26, 3p24, and 7q35 (50%). We did not find any microsatellite instability. Our results suggest that in addition to a group of TSGs, pleiotropic for several tumor types, other suppressor genes are specifically involved in oral and oropharyngeal carcinogenesis.

[Calf muscle venous thrombosis and pulmonary embolism]

INTRODUCTION

The clinical significance of calf muscle venous thrombosis (CMVT) still remains a matter of debate. Detected by ultrasonography, they are overlooked by venography. This prompted us to evaluate the frequency of such localizations and their association to pulmonary embolism (PE).

METHODS

Retrospective review of our database over a three-year period. All patients with an isolated CMVT were included.

RESULTS

Isolated CMVT were detected in 106 patients (mean age 68.6 years; 65% women), that is 12.5% of all venous thromboses diagnosed in the vascular sonography unit over the study period Sixteen associated PE were detected (15%).

CONCLUSIONS

Association of CMVT and PE is not infrequent. Whether or not such thromboses have the potential to extend into deep veins and/or to migrate into pulmonary circulation requires further studies.

Highly sensitive chemiluminescent method for the detection of cell contamination

Minisatellite analysis is commonly used in forensic disputes but can also be applied to the investigation of cell contamination. Such a problem arises, for example, when transplantation is performed. The presence of contamination has been investigated by other authors using radioactive methods. In the present study we describe a method that allows the detection of contamination with high sensitivity without using radioactive substances. Our technique is based on the use of polymerase chain reaction (PCR) amplification of minisatellite sequences (VNTR), followed by chemiluminescent detection. In particular, biotin-labelled dCTP is included in the PCR mixture and detection of PCR products is obtained following the CSPD chemiluminescent protocol (Southern-Light Nucleic Acid Detection Systems). We applied this method to artificial mixes of DNA of two individuals with alleles of different sizes. We performed progressive dilutions of an individual DNA into the other's DNA and revealed a contamination of 1 in 2500 cells. We also tested our technique searching for maternal contamination in cord blood samples in 60 cases and revealed a 18.3% contamination. The technique that we set up proves to be a very sensitive one which could be applied not only to the detection of maternal cells in cord blood but also in studying any other kind of contamination.

Improved blood substitute: evaluation of its effects on human endothelial cells

The authors have previously documented that appropriate chemical and pharmacologic modification of the hemoglobin molecule are required to attenuate certain pathophysiologic reactions of the reticuloendothelium. The current study further investigates the molecular responses of human coronary artery endothelial cells to a high concentration (0.4 mmol) of 1) unmodified bovine hemoglobin; and 2) an improved blood substitute that comprises hemoglobin cross-linked intramolecularly with o-adenosine triphosphate and intermolecularly with o-adenosine, and conjugated with reduced glutathione. In this study, the scavenging effect of hemoglobins toward nitric oxide (NO) was evaluated by the measurement of nitrite (NO2-) and nitrate (NO3-) formation. The pro-oxidant effect of hemoglobin on endothelial cells was examined by the measurement of intracellular reduced glutathione, and by monitoring the formation of lipid hydroperoxides and 8-iso prostaglandin F2alpha, a novel potent vasoconstrictor, which is produced by a noncyclooxygenase mechanism involving free radical catalyzed peroxidation of arachidonic acid. The inflammatory reactions of endothelial cells were evaluated by the expression of the adhesion molecule, intracellular adhesion molecule-1, and the activation of nuclear transcription factor, nuclear factor kappaB. In additional, endothelial cell responses were investigated by analysis of intracellular ionized calcium concentrations. Results indicate that unmodified hemoglobin in a concentration of 0.4 mmol/L can aggravate endothelial cell oxidative and inflammatory responses. This hemoglobin produced a significant (p < 0.01) depletion of reduced glutathione, acceleration of lipid peroxidation, and a greater influx of Ca2+. The formation of 8-iso prostaglandin F2alpha increased compared with the control cells (p < 0.01). Unmodified hemoglobin was found to be a potent scavenger of NO, great activator of nuclear factor kappaB, and a stimulator of intracellular adhesion molecule-1 expression. Contrarily, the improved blood substitute did not appear to induce oxidative stress nor to increase the intracellular Ca2+. The concentration of 8-iso prostaglandin F2alpha was similar to that in the control cells, whereas the formation of NO2-/NO3- was much lower (p < 0.05) than in the unmodified hemoglobin group. The effect of an improved blood substitute can be linked with the anti-inflammatory and cytoprotective properties of adenosine, which is used as a cross-linker and surface modifier, and the type of the chemical modification procedure that lowers hemoglobin pro-oxidant potential.

Trisomic zygote rescue revealed by DNA polymorphism analysis in confined placental mosaicism

Uniparental disomy can be caused by different genetic mechanisms such as gamete complementation, chromosome duplication in monosomic zygote, or post-zygotic aneuploidy correction. This last mechanism is well documented in human reproduction and is related to placental mosaicism. In the case of a trisomic zygote which has originated by paternal or maternal non-disjunction at the first or second meiotic cell division, mosaicism will result from chromosome loss and restoration of a 'normalized' diploid fetal karyotype. In order to enrich the literature with new observations on this subject, we studied by DNA polymorphism analysis ten cases of confined placental mosaicism (CPM). The finding in placental DNA of three different alleles at polymorphic loci of chromosomes 13, 16, and 20 demonstrated the trisomic status of the zygote in three cases. On the basis of these results, we believe that systematic DNA polymorphism analysis could give useful additional information to improve knowledge on aneuploidy correction in human reproduction.

Intrarenal arteriosclerosis and impairment of kidney function in NIDDM subjects

It is currently under debate whether the pathogenesis of end-stage renal failure in non-insulin-dependent diabetes mellitus (NIDDM) is a consequence of microangiopathy alone. The aim of this study was to investigate intrarenal arteriosclerosis and its correlation with kidney function in NIDDM. In 36 diabetic subjects, and in 10 age- and sex-matched healthy control subjects we measured kidney volume and resistive index of the interlobar arteries by duplex Doppler ultrasonography. Clinical and metabolic parameters, renal function and vascular sequelae of the disease were also evaluated. In diabetic subjects resistive index (median 0.72, range 0.54-0.79) was higher than in control subjects (median 0.62, range 0.57-0.66) (2p < 0.002). Kidney volume and resistive index correlated with age (p < 0.004), body mass index (p < 0.001), mean blood pressure (p < 0.001), total and LDL cholesterol (p < 0.01) and creatinine clearance (p < 0.001 and < 0.01, respectively). Kidney volume also correlated with HbA1 (p < 0.01) and resistive index with uric acid (p < 0.01). Lower body macroangiopathy was associated with increased resistive index and reduced kidney volume (2p < 0.05), while upper body macroangiopathy and microangiopathy were not. Our data suggest that macroangiopathy rather than microangiopathy is mainly responsible for impairment of kidney function in NIDDM. The resistive index of interlobar arteries seems to be a reliable marker of intrarenal arteriosclerosis and can be used as a non-invasive, easily available parameter of its evolution.

[Analysis of risk factors in patients operated for abdominal aortic aneurysm]

BACKGROUND

The incidence of the associated risk factors on the early results of elective repair of abdominal aortic aneurysms has been evaluated in a series of 270 consecutive patients. Clinical, hematological and instrumental data concerning cardiovascular, pulmonary and metabolic diseases have been collected for each patient, as well as the type and the results of the surgical procedure.

METHODS

The graft was straight aortic in 82 cases (30.3%), aorto-bisiliac in 130 (48.1%) and aorto-bifemoral in 58 cases (21.6%); the 237 uneventful patients (87.8%) have been discharged 8 days after the operation (mean) and 24 (8.9%) underwent to coronary-aortic bypass graft (CABG) previously.

RESULTS

Postoperative complications have been observed in 33 patients (12.2%): 24.3% pulmonary, 21.2% cardiac and 15.1% renal and among these 13 patients died (4.8% of the complete series and 39.4% of those with complications) because of pulmonary (38.4%), cardiac (30.7%) and renal causes (23.3%) mainly. Despite the complications occurred mainly in patients with associated risk factors, the multivariate analysis has shown that only the chronic obstructive pulmonary disease (COPD) plays a fundamental role (p < 0.005). On the contrary, among the patients died not one single risk factor reached statistical significance, although the COPD was close (p = 0.1).

CONCLUSIONS

These data underline the need of a careful evaluation and treatment of associated diseases in patients undergoing elective repair for an AAA; namely a screening for asymptomatic coronary artery disease, since the CABG can significantly reduce morbility and mortality rates, and for COPD. In addition a more careful monitoring of patients with long clamping time could reduce the possible related renal complications. Up to now, since the surgical procedures is already standardized, the precise diagnosis and treatment of associated risk factors represent the winning strategy for the achievement of better results.

An improved blood substitute. In vivo evaluation of its renal effects

Nephrotoxicity of free hemoglobin (Hb) based blood substitutes still awaits full elucidation. Previous reports attributed Hb passage through the renal glomeruli to a tendency of the Hb tetramer to dissociate into dimers. Now it has become more evident that the Hb tetramer is able to extravasate. It appears that the electrical charge of proteins plays an important role, with electronegativity and a low isoelectric point favoring intravascular persistence. This effect was utilized in the development of an improved blood substitute, comprising Hb reacted with o-ATP and o-adenosine, to form an intra- and intermolecularly cross linked product, which is reduced with glutathione. The modification reagents possess the desired pharmacologic activities and produce an increase in the electronegative charges on the Hb surface. All Hb polymers and chemically modified tetramers present in this solution have a uniform electronegative charge, with a pl of 6.1-6.2. In this present study, unmodified bovine Hb and an improved blood substitute were used for the replacement of 40% of the total blood volume in rats. The nephrotoxic effect was investigated by the determination of urinary output, glomerular filtration rate (GFR), fractional excretion of sodium (FENa), potassium (FEK), and chloride (FECl), urine/plasma osmolality ratio, and urine N-acetyl-beta-D-glucosaminidase (NAG) level. The free Hb and non heme protein contents in the urine were analyzed by using isoelectric focusing and size exclusion liquid chromatography methods. The results indicate that unmodified Hb is nephrotoxic. An initially elevated urinary output was followed by a significant oliguria associated with decreased GFR, FEK, and FECl and elevated FENa and NAG. Severe hemoglobinuria was associated with proteinuria. Analysis of urine from unmodified Hb treated rats revealed the presence of Hb tetramers. Histopathological examination of the kidneys showed cytoplasmic vacuolization of proximal tubular epithelium. On the contrary, an improved blood substitute did not produce any nephrotoxic reactions. It was found that this Hb solution did not pass through the renal glomerular barrier and was not present in urine samples. In conclusion, such a chemical and pharmacological alteration of Hb molecules reduced their interaction with renal glomeruli and suspended nephrotoxicity.

[Congenital hypothyroidism screening program: preliminary results]

OBJECTIVE

The authors report early results of a screening program for Congenital Hypothyroidism in Santa Catarina, Brazil.

METHODS

All the assays (82.709) analysed by Laboratório Central (LACEN) between July 1993 and December 1994 were studied. A blood sample was collected on filter paper for serum Thyroid Stimulating Hormone (TSH) measurement by fluoroimmunoassay, in triplicate. All children who had persistent abnormal TSH values (cord blood: TSH > 30 micro U/ml; from 2 to 7 days: >20 micro U/ml; older than 7 days: > 10 micro U/ml) were recalled for clinical evaluation.

RESULTS

Out of 82.709 infants aged from 0 to 60 days (40% of the deliveries in this period), 304 presented abnormal results of TSH and 34 were confirmed as Congenital Hypothyroidism. The mean age of beginning the treatment was 45 days of life.

CONCLUSIONS

The prevalence (1:2500) was higher than that observed in other countries, probably because some children had Transient Congenital Hypothyroidism. Nevertheless, sex prevalence was similar to that described in the literature. Clinical manifestations were inespecific which reinforces the importance of this kind of screening. Efforts have been done to improve the program in order to begin earlier treatment.

Cytogenetic abnormalities and microsatellite instability in endometrial adenocarcinoma

Recently various authors described a new mechanism involved in the genesis of some tumors, which is characterized by a tendency for replication mistakes and by genomic instability of microsatellite repeats. This instability can be revealed through the shift in the electrophoretic mobility of the analyzed fragments, which is due to a different number of repeat units. This phenomenon is widely documented in colorectal tumors of patients affected by hereditary nonpolyposis colorectal carcinoma (HNPCC). We performed a cytogenetic and molecular study of 23 endometrial adenocarcinomas to investigate the presence of genomic instability and to evaluate the possibility of a positive correlation with specific chromosomal changes. The study of genomic instability was performed using 23 microsatellites localized over 8 chromosomes. Genomic instability of microsatellites was observed in 3 cases over all 8 analyzed chromosomes. The tumoral stage of cases with microsatellite instability does not differ significantly from the remaining tumors. As a matter of fact several cases showing no evidence of instability were more advanced (II B, III A) than tumors with instability. In ten cases we observed trisomy of chromosome 10, in some as a sole anomaly. The 3 cases with genomic instability revealed a near-diploid karyotype and all showed the presence of a supernumerary marker derived from chromosome 1 rearrangements. A derivative chromosome 1 was revealed in 4 cases without evidence of microsatellite instability. It should be noted that the presence of many unidentified markers and the small number of tumors with instability do not allow us to give a definitive significance to this observation. Our results indicate that there is not an apparent correlation between microsatellite instability and specific chromosomal abnormalities. Moreover, we did not find any correlation between pathological characteristics of the tumor and genomic instability. Microsatellite instability appears to be a relatively rare event in endometrial carcinoma.

[Performance and complications of totally implantable port device in bolus hepatic intra-arterial chemotherapy]

The performances of totally implantable ports were analyzed in patients with colorectal metastases undergoing intraarterial treatment. Seventy-nine patients received bolus infusion of Cisplatin (DDP, 57 cases) or Epirubicin (EPI, 22 cases) every 21 and 7 days, respectively. Disease progression or toxicity were the most common causes of interruption of treatment, whereas failure of ports occurred in six and two patients out of DDP and EPI groups, respectively. The incidence of single problems for each port was 65% in DDP group and 64% in EPI group, whereas rate of complications for each patient was 30% and 32%, respectively. The 12-months device duration rate in the two groups was 65% (median 17 months) in DDP group and 78% (median 18 months) in EPI group. The implantable ports employed for bolus arterial infusion, allowed adequate treatment periods in most cases, without any difference as far as intervals between cycles is concerned.

Modified hemoglobin solution, with desired pharmacological properties, does not activate nuclear transcription factor NF-kappa B in human vascular endothelial cells

The aim of the present study was to evaluate the role of hemoglobin (Hb) and the contribution of chemically modified Hb solutions on the activation of nuclear transcription factor. NF-kappa B, and propagation of oxidative stress within human vascular endothelial cells. The activation of an oxidative stress-sensitive NF-kappa B can be linked with the propagation of an inflammatory state via rapid induction of genes for several pro-inflammatory mediators. Human coronary artery endothelial cells (HCAEC) were cultured on glass coverslips or cell culture plates to confluence. Then, the cells were incubated for up to 18 hours with endothelial basal medium (EBM) supplemented with 5% FBS and test agents in a concentration of 0.1 and 0.2 mmol: 1) unmodified bovine Hb (UHb): 2) modified Hb solution polymerized with glutaraldehyde (GLUT-Hb), and 3) a novel modified Hb solution (Hb-PP-GSH) prepared according to our patented procedure (U.S. Patent No. 5,439,882). The positive control for the NF-kappa B activation study included a treatment of the cells with: I) endotoxin: IL-1; TNF; and H2O2. Results indicate that Hb's pro-oxidant potential was influenced by the type of chemical modification procedure. The GLUT-Hb autoxidation rate, peroxidase-like activity and reactivity with H2O2/ferryl species formation were higher as compared to UHb, by 15%, 35% and 30%, respectively. However, pro-oxidant potential of Hb-PP-GSH was significantly lower than that of UHb (by 22%, 12% and 28%, respectively). The extent of oxidative stress of the HCAECs was found to be the Hb modification-type and concentration dependent. Although the highest endothelial lipid peroxidation and the largest depletion of intracellular GSH was associated with 0.2 mmol of GLUT-Hb, the Hb-PP-GSH did not produce significant changes when compared to the control cells. The UHb generated a moderate oxidative stress to the endothelium. The immunofluorescent and EMSA results indicate a correlation between the type of Hb chemical modification and the induction of NF-kappa B nuclear translocation. We found that GLUT-Hb rapidly activated NF-kappa B and induced nuclear translocation. Treatment of the cells with an increasing amount of UHb leads to the partial nuclear induction of NF-kappa B. However, Hb-PP-GSH did not activate NF-kappa B directly. In this study, the positive control cells treated with endotoxin, IL-1 or TNF demonstrated full nuclear translocations, whereas H2O2 caused only partial induction. In conclusion, nuclear translocation of NF-kappa B by Hb solutions might be dependent on Hb's pro-oxidant potential and extent of Hb-mediated endothelial oxidative stress. Besides the low oxidative potential of Hb-PP-GSH, the observed lack of NF-kappa B activation by this Hb solution can be also related to the anti-inflammatory properties of adenosine which is used in our novel modification procedure. In this study, only the Hb-PP-GSH, cross-linked intramolecularly with o-adenosine triphosphate and intermolecularly with o-adenosine, and combined with reduced glutathiore, was shown to be non-toxic to the endothelium and promises to be an effective free-Hb based blood substitute.

Expression of adhesion molecules and von Willebrand factor in human coronary artery endothelial cells incubated with differently modified hemoglobin solutions

Previous studies have established a linkage between free Hb molecules and the production of inflammatory mediators by the reticuloendothelial cells. An important aspect of the endothelial response to the inflammatory stimuli is the expression of adhesion molecules on the luminal surface. Therefore, the present study was designed to investigate the effects of various free-Hb based oxygen carrying solutions on the intracellular adhesion molecule-1 (ICAM-1), the vascular cell adhesion molecule-1 (VCAM-1) and also von Willebrand factor (vWF) expression by human endothelium. Human coronary artery endothelial cells (HCAEC) were cultured on glass coverslips until they reached confluence, then incubated for 18 hours with endothelial basal medium (EBM) supplemented with 5% FBS and a 0.1 mmol or 0.2 mmol of the bovine Hb solutions: 1) pure unmodified bovine Hb (UHb); 2) modified bovine Hb solution (Hb-PP-GSH) prepared according to our newly developed procedure (U.S. Patent No. 5,439,882); and 3) modified bovine Hb solution polymerized with glutaraldehyde (GLUT-Hb). The HCAECs were also incubated with EBM (negative control) and EBM containing bacterial endotoxins in a concentration of 50 EU/ml (positive control). After treatment, cells were exposed to primary antibodies; anti-human ICAM-1, anti-human VCAM-1 or anti-human vWF, and consequently to the secondary antibody (fluorescein isothiocyanate-conjugated F(ab)2). Immunofluorescence analysis revealed different expressions of ICAM-1 and VCAM-1 on the surface membranes of variously treated cells. Although negative control cells had an undetectable level of adhesion molecules, the positive control cells, activated by endotoxin, exhibited high immunoreactivity for ICAM-1 and VCAM-1. The Hb's treated cells demonstrated differing degrees of activation. An insignificant expression of ICAM-1 was observed in HCAEC, following treatment with a 0.1 or 0.2 mmol of Hb-PP-GSH and 0.1 mmol of UHb. Cell treated with 0.2 mmol of UHb and both concentrations of GLUT-Hb demonstrated a massive expression of this adhesion molecule. A similar effects was observed during induction of VCAM-1. While a lack of expression was noted with both concentrations of Hb-PP-GSH and 0.1 mmol of UHb, the GLUT-Hb stimulated significant VCAM-1 induction at all tested concentrations. Immunofluorescence analysis confirmed the expression of vWF uniformly in HCAEC from the different experimental groups. The data suggest, vWF expression was unaffected by all but the GLUT-Hb treatment. In conclusion, the Hb stimulatory activity toward ICAM-1 and VCAM-1 inductions were related with the type of Hb chemical modification method. Although modification of Hb with glutaraldehyde potentiates adhesion molecules expression, our novel Hb modification procedure, which comprises intramolecular cross-linking with o-adenosine triphosphate and intermolecular with o-adenosine, and combined with reduced glutathione, apparently prevents these inflammatory events.

[The Hickman catheter as vascular access in bone marrow transplantation]

From 1984 to 1995, 522 Hickman catheters were placed in the Institute of Clinica Chirurgica B of the University of Genova to treat malignant haemathologic diseases. Aims and reasons of this choice, surgical technique, advantages and related problems are reported here.

Helical CT for the study of abdominal aortic aneurysms in patients undergoing conventional surgical repair

OBJECTIVES

To evaluate the reliability of helical computed tomography (CT) as sole preoperative diagnostic technique for abdominal aortic aneurysms (AAA) and to compare these results with the surgical findings.

MATERIALS

Thirty-three patients undergoing elective surgical repair.

METHODS

Helical CT, Doppler exam of lower limbs, digital angiography, in case of peripheral vascular disease, and intraoperative evaluation.

RESULTS

Helical CT correctly detected, in all cases, the proximal and distal extent of the AAA. The coeliac axis and its branches, the superior mesenteric artery and renal vessels as well as the inferior vena cava were always clearly depicted, showing anatomical variants or pathological involvement in 14 patients (42.4%).

CONCLUSIONS

Helical CT can be used as the sole method for preoperative imaging of AAA. It allows a complete and precise evaluation of size, extent and relationship of the AAA, the surrounding vessels and other abdominal structures.

First-trimester chromosome diagnosis by lavage of the uterine cavity

Fetal karyotyping of trophoblast cells obtained by lavage of the uterine cavity was evaluated on 86 first-trimester irrigation fluid samples. Villus fragments were observed in 72 fluid samples indicating an 83.7 per cent sampling success rate. The amount of villi in these samples ranged from 1 to 32 mg. In most cases, villus fragments showed degeneration of the external syncytiotrophoblast layer and absence of blood vessels. In the first phase of this study (15 samples), a high degree of maternal cell contamination was observed after long-term cultures. In the following phase (71 samples), this obstacle was overcome by the application of a semi-direct method. Chromosome preparations were set up after 24 h incubation of villus fragments and QFQ-banded metaphase spreads were scored for chromosome number and sex. Sixty samples showed the presence of villus fragments and the fetal karyotype was established in 40. Male and female chromosome complements were observed in 16 and 24 cases, respectively. In four cases, an abnormal fetal karyotype was diagnosed. These included trisomy of chromosomes 13, 15, and 16, and one mosaic with trisomy 12. Our results indicate that first-trimester fetal karyotyping might be feasible by a semi-direct method using chorionic villus fragments obtained at intrauterine lavage.

An improved blood substitute. In vivo evaluation of its hemodynamic effects

The purpose of the present study was to assess the ability of an improved free hemoglobin based blood substitute to serve as a resuscitative fluid in the treatment of hemorrhagic shock. Comparison studies were performed by using blood autotransfusion as a positive control. The hemodynamic parameters studied included cardiac index, mean arterial pressure, pulse pressure, heart rate, stroke volume index, and total peripheral resistance. Tissue oxygenation was measured in the biceps femori muscle by polarography. Hemorrhagic shock (at 40% of the total blood volume) in anesthetized rats caused severe disturbances in hemodynamic parameters and tissue oxygenation. Shock was characterized by a 66% drop in cardiac index, a 67% drop in mean arterial pressure with a significant increase in total peripheral resistance, and a 78% reduction in tissue oxygenation, all lasting 30 min. Resuscitation from shock with the blood substitute was effective in restoring hemodynamic parameters, producing vasodilation, and improving tissue oxygenation. Autotransfusion with blood also restored hemodynamics. However, lower tissue oxygenation and lack of vasodilation were noted. Therefore, the modified hemoglobin solution yielded better results than blood in the resuscitation of rats after hemorrhagic shock. The vasodilatory activity and the reduction of vasoconstriction that followed hemorrhage can be primarily linked with adenosine, which possesses vasodilatory and anti-inflammatory properties, and is used in our technology as an intermolecular cross linking reagent and hemoglobin surface modifier.

Does the presence of heparin and dexamethasone in the vitrectomy infusate reduce reproliferation in proliferative vitreoretinopathy?

BACKGROUND

Reproliferation following vitrectomy for proliferative vitreoretinopathy (PVR) causes redetachment in up to 55% of cases. Heparin and corticosteroids have each been shown to inhibit the development of proliferative vitreoretinopathy (PVR) in experimental models. However, little information is available on the use of these agents in humans.

METHODS

In this pilot study, 62 eyes of 62 patients with severe PVR requiring vitrectomy were prospectively randomized to receive either BSS Plus (control) or BSS Plus with heparin and dexamethasone (HD) in the infusate.

RESULTS

After one operation, the retina was reattached in 42 (71%) of 59 eyes: 22 (65%) of 34 eyes in the control group and 20 (80%) of 25 eyes in the HD group (P = 0.16). Reproliferation developed in 26.5% of the control group (9 of 34 eyes) and 16% of the HD group (4 of 25 eyes; P = 0.26). Postoperative hemorrhage was significantly more frequent in the HD group (P = 0.02) but did not influence final visual or anatomic outcome. Hypotony was less frequent in the HD group but the difference was not significant (P = 0.063).

CONCLUSION

The trend from this randomized pilot study suggests that HD supplementation of the vitrectomy infusate may reduce the reproliferation rate in PVR and possibly reduce the rate of hypotony. Postoperative hemorrhage was more frequent with HD but did not cause redetachment or alter visual outcome. A multicenter trial involving more patients would be required to better evaluate the efficacy of HD as a pharmacologic adjunct to PVR surgery.