[Influence of inlay height on motion characteristics of lumbar segments in total disc replacement]

AIM OF THE STUDY

Maintaining segmental motion is one of the most reported theoretical advantages of total disc replacement (TDR). Several inlay sizes are available for reconstruction of the physiological disc height. The influence of the implant height on the range of motion (ROM) was investigated in a biomechanical study.

METHODS

A total of 10 human lumbar cadaver spines were subjected to biomechanical testing. Flexion/extension and side-bending moments were applied from 2.5-7.5 Nm on a spine load simulator allowing for all 6 degrees of freedom. Motion under different loads was monitored by the Zebris system in 3 dimensions. Initially intact specimens were tested in 3 load cycles. Then a total disc prothesis was implanted with an 8.5 mm inlay and the cycles were repeated. Finally in 5 cases a 1-mm larger inlay was inserted while in the remaining 5 cases the inlay was exchanged with a 2-mm larger implant. Neutral zone (NZ) and ROM were recorded under the different loads.

RESULTS

The average motion for the various loads showed no significant difference when the intact motion segment was compared to the specimen containing the 8.5-mm inlay. After the larger inlay had been mounted the average reduction of the ROM in flexion/extension was 25% under the load of 7.5 Nm, 26% under a torque of 5.0 Nm and 30% when 2.5 Nm were applied. The NZ was reduced by 37%. For side-bending the ROM was reduced by 21% under a load of 7.5 Nm, by 26% under 5.0 Nm and by 35% under a torque of 2.5 Nm. The NZ was decreased by 27%. The reduction of the ROM was significant (p=0.0057).

CONCLUSION

Segmental lumbar motion is maintained after TDR. The size of the inlay can significantly change the ROM in lumbar spine segments treated by TDR.

Structural and functional properties of hydration and confined water in membrane interfaces

The scope of the present review focuses on the interfacial properties of cell membranes that may establish a link between the membrane and the cytosolic components. We present evidences that the current view of the membrane as a barrier of permeability that contains an aqueous solution of macromolecules may be replaced by one in which the membrane plays a structural and functional role. Although this idea has been previously suggested, the present is the first systematic work that puts into relevance the relation water-membrane in terms of thermodynamic and structural properties of the interphases that cannot be ignored in the understanding of cell function. To pursue this aim, we introduce a new definition of interphase, in which the water is organized in different levels on the surface with different binding energies. Altogether determines the surface free energy necessary for the structural response to changes in the surrounding media. The physical chemical properties of this region are interpreted in terms of hydration water and confined water, which explain the interaction with proteins and could affect the modulation of enzyme activity. Information provided by several methodologies indicates that the organization of the hydration states is not restricted to the membrane plane albeit to a region extending into the cytoplasm, in which polar head groups play a relevant role. In addition, dynamic properties studied by cyclic voltammetry allow one to deduce the energetics of the conformational changes of the lipid head group in relation to the head-head interactions due to the presence of carbonyls and phosphates at the interphase. These groups are, apparently, surrounded by more than one layer of water molecules: a tightly bound shell, that mostly contributes to the dipole potential, and a second one that may be displaced by proteins and osmotic stress. Hydration water around carbonyl and phosphate groups may change by the presence of polyhydroxylated compounds or by changing the chemical groups esterified to the phosphates, mainly choline, ethanolamine or glycerol. Thus, surface membrane properties, such as the dipole potential and the surface pressure, are modulated by the water at the interphase region by changing the structure of the membrane components. An understanding of the properties of the structural water located at the hydration sites and the functional water confined around the polar head groups modulated by the hydrocarbon chains is helpful to interpret and analyze the consequences of water loss at the membranes of dehydrated cells. In this regard, a correlation between the effects of water activity on cell growth and the lipid composition is discussed in terms of the recovery of the cell volume and their viability. Critical analyses of the properties of water at the interface of lipid membranes merging from these results and others from the literature suggest that the interface links the membrane with the aqueous soluble proteins in a functional unit in which the cell may be considered as a complex structure stabilized by water rather than a water solution of macromolecules surrounded by a semi permeable barrier.

Activation of interferon response genes and of plasmacytoid dendritic cells in HIV-1 positive subjects with GB virus C co-infection

GB virus C (GBV-C) coinfection has a protective role in Human Immunodeficiency Virus (HIV) infection, and increases the duration of suppression of HIV-1 viremia in patients under Highly Active Anti-Retroviral Therapy (HAART). Since innate antiviral response may be involved in the protection, we analyzed the possible role of GBV-C as activator of innate immunity. To this aim, we measured the extent of activation of the interferon (IFN) system and of circulating Dendritic Cells (DC) in vivo, and the ability of GBV-C to activate these functions in vitro. Activation of IFN system and of circulating DC was compared in GBV-positive and -negative HIV-1 co-infected patients with HAART-driven suppression of HIV-1 viremia. Endogenous levels of IFN-gamma and RNA-dependent protein kinase (PKR) mRNA were significantly higher in peripheral blood mononuclear cells (PBMC) from GBV-C-positive when compared to GBV-C-negative patients. IFN-gamma expression was correlated with all the Interferon response genes (IRGs) and with GBV-C viremia. The frequency of circulating plasmacytoid DC (pDC) expressing the CD80 activation marker was increased in GBV-C-positive patients, and was correlated with GBV-C viral load. In vitro experiments indicated that GBV-C is able to induce IFN-gamma expression in PBMC. In addition, in PBMC cultures GBV-C induced an increase of CD80 expression by pDC, that was reduced by antibody to IFN-gamma. Our data indicate that in HIV-positive patients GBV-C coinfection promotes the activation of IFN-gamma and downstream IRG expression, as well as with the activation/maturation of circulating pDC. GBV-C-driven IFN-gamma activation is, at least in part, responsible for the increased maturation of pDC. This crosstalk may suggest a role for GBV-C coinfection in boosting the innate antiviral response to HIV infection.

Proinflammatory cytokines and hemostatic system in patients with chronic obstructive pulmonary disease

The prothrombotic state frequently observed in patients with chronic obstructive pulmonary disease (COPD) may be related to a systemic inflammatory response. In the present study plasma interleukin-6 (IL-6), IL-2 and IL-1beta levels have been investigated in 33 patients with COPD. In vitro platelet activity, plasma C-reactive protein (CRP) and fibrinogen levels were also determined in all patients. The results obtained demonstrated that plasma IL-6 levels were significantly higher in the patient group compared with a control population age and sex-matched ( P < 0.02), while plasma IL-2 and IL-1beta levels were not significantly modified. An overall condition of platelet hyperactivity in COPD patients was also observed. A comparative analysis of platelet activity and blood gas levels demonstrated a correlation between platelet hyperactivity and a severe impairment of oxygen ( P < 0.001) and carbon dioxide tensions ( P < 0.01). Finally, a statistical analysis of the population under study showed the presence of a significant correlation between elevated plasma IL-6 ( P < 0.001) and IL-1beta levels ( P < 0.007), and an increased sensitivity of platelets to arachidonic acid, suggesting a possible correlation between the inflammatory response and the prothrombotic state observed in patients with COPD.

Chronic sub-lethal oxidative stress by spermine oxidase overactivity induces continuous DNA repair and hypersensitivity to radiation exposure

In the aging process and in most degenerative diseases, the oxidant by-products of cellular metabolism lead to oxidative stress. Oxidative stress plays an important role in switching from cell proliferation to its opposite outcome, cell death. The metabolic pathways in charge of the interconversion and degradation of the polyamines are responsible for oxidant by-products. In the past few years, spermine metabolism has been found closely related to DNA oxidation and apoptosis. Moreover, that the ectopical expression of murine spermine oxidase induced DNA damage in the neuroblastoma cell line, and this was uncoupled with any increase in cell mortality, thus suggests an activation of DNA repair. In this work, we provide new evidence showing that only spermine oxidase overactivity can deliver sub-lethal chronic DNA damage and repair without affecting transcriptional and enzymatic levels of the PA key regulatory enzymes ODC and SSAT. Chronic sub-lethal DNA damage is below the cell cycle arrest induction threshold, but is able to activate apurinic/apyrimidinic endonuclease protein (APE1) and gamma H2AX. Of therapeutic interest, the chronic sub-lethal DNA damage and activation of the repair processes are in turn responsible for inducing hypersensitivity after exposure to radiation with no induction of adaptive response to damage.

Virological characterization of patients treated early is able to control HIV-1 replication after multiple cycles of structured therapy interruption

This study aimed to define clinical and virological parameters associated with spontaneous control of HIV replication in patients having initiated HAART during primary HIV infection, who underwent structured therapy interruption by two protocols with either fixed or HIV viremia-guided scheme. At the end of the protocol all patients were changed to viremia-guided scheme and observed for 12 months (follow-up). Patients maintaining HIV viremia below the indications for resumption of HAART during the follow-up, were defined controllers, those who had to resume HAART were defined non-controllers. The following parameters were examined: pre-interruption therapy duration, CD4(+), HIV RNA, proviral DNA, evolution of viral quasispecies. No specific advantage was conferred by either interruption of structured therapy in the proportion of controllers and non-controllers. Pre-HAART and zenith CD4(+), pre-therapy interruption, HAART duration, but not pre-HAART HIV RNA, were significantly higher in controllers as compared to non-controllers. HIV RNA levels after the first interruption cycle of therapy were significantly lower in controllers than in non-controllers. Proviral DNA levels were also lower in controllers at this time point. HIV RNA and proviral DNA levels associated with the last interruption of therapy cycle were not different from those associated with the first cycle, and, in spite of multiple waves of virus rebound, very few gag quasispecies variants emerged in each patient. The data suggest that pre-treatment clinical parameters and virological events associated with the first viral rebound are crucial factors in determining the ability to control viral replication after multiple cycles of interruption of treatment.

Peri-prosthetic bone density after implantation of a custom-made femoral component. A five-year follow-up

Peri-prosthetic bone loss caused by stress shielding may be associated with aseptic loosening of femoral components. In order to increase primary stability and to reduce stress shielding, a three-dimensional, cementless individual femoral (Evolution K) component was manufactured using pre-operative CT scans. Using dual energy x-ray absorptiometry, peri-prosthetic bone density was measured in 43 patients, three months, six months, 3.6 and 4.6 years after surgery. At final follow-up there was a significant reduction in mean bone density in the proximal Gruen zones of -30.3% (zone 7) and -22.8% (zone 1). The density in the other zones declined by a mean of between -4% and -16%. We conclude that the manufacture of a three-dimensional, custom-made femoral component could not prevent a reduction in peri-prosthetic bone density.

Influence of GBV-C infection on the endogenous activation of the IFN system in HIV-1 co-infected patients

BACKGROUND

GB virus C (GBV-C) co-infection is associated with a better prognosis in HIV-infected persons. Since interferon activation can be one of the possible mechanisms involved in GBV-C-driven protection against HIV, we compared the endogenous activation of the interferon system in PBMC from GBV-C-positive and -negative patients infected with HIV-1.

METHODS

The expression of interferon related genes was analyzed in 20 GBV-C positive and 20 GBV-C-negative HIV-infected patients, comparable in terms of CD4 cell counts and HIV viral loads. The levels of mRNA for interferon-related genes (2-5-OAS, MxA, interferon AR-1 and PKR) in PBMC were measured by real time RT-PCR, using B-actin as internal control.

RESULTS

The endogenous levels of all the Interferon-related genes in HIV/GBV-C co-infected patients were higher than in HIV mono-infected subjects. The difference was statistically significant for PKR mRNA. Direct positive correlation was found between PKR and all the other interferon-related genes, suggesting a coordinated activation of the interferon system.

CONCLUSIONS

Enhanced activation of the interferon system occurs in GBV-C-positive, as compared to GBV-C-negative patients harbouring HIV-1. These data may be relevant to understand the GBV-C-driven protection against HIV, suggesting that the endogenous activation of the interferon system can contribute to the control of HIV replication.

Specific features of differentiated thyroid carcinoma in patients over 70 years of age

BACKGROUND AND OBJECTIVES

Among the geriatric population, there is a lower incidence of thyroid carcinoma (TC), but it accounts for 30% of all thyroid disorders compared to 6-8% in younger subjects. Prognosis, moreover, is worse in the elderly, as demonstrated by the fact that 81% of deaths related to these tumors occur in patients over 55. The aim of this retrospective study was to identify the characteristics of differentiated thyroid carcinoma (DTC) peculiar to the elderly.

METHODS

Of 638 patients who underwent surgery for DTC over a period of 30 years, 46 were more than 70 years old. All the elderly patients had undergone radioioidine and TSH-suppression therapy following surgical resection.

RESULTS AND CONCLUSIONS

Despite these measures, the rate of recurrence was 26.5% at 5 years and 63.6% at 10 years. The 5- and 10-year disease-specific survival rates were 87.8% and 63.6%, respectively. On an average, survival was 55.1 months when death was disease-related, and with regard to histological type, it was longer in papillary carcinoma than in the follicular variant, and longest of all in occult sclerosing carcinoma. Survival was greatest in patients with tumors less than 2 cm in diameter, characterized by the absence of extraglandular spread and by lymph node metastasis.

T cell selection and differentiation in AIDS disease: the model of HIV-discordant monozygotic twins

The model of monozygotic twins has been repeatedly studied to control the genetic and age-specific effects on HIV disease. Focusing on this natural model, the expression of CD27/CD45RA differentiation markers and the distribution of the Vbeta TCR repertoire was analyzed on CD4+ and CD8+ T cells. In our HIV-discordant monozygotic twins, a significant reduction of naive T cells and a parallel accumulation of effector/memory T cells was induced by HIV infection, as well as a skewing of T cell repertoire evidenced by VbetaTCR analysis. The block of HIV replication by highly active antiretroviral therapy (HAART) restored most of the T cell maturation and selection process, with some exception among CTL differentiation and repertoire. Altogether, the model of HIV-discordant monozygotic twins is a valuable tool showing that HAART is not able to completely restore the CTL profile.

T-Cell response profiling to biological threat agents including the SARS coronavirus

The emergence of pathogens such as SARS and the increased threat of bioterrorism has stimulated the development of novel diagnostic assays for differential diagnosis. Rather than focusing on the detection of an individual pathogen component, we have developed a T cell profiling system to monitor responses to the pathogens in an array format. Using a matrix of antigens specific for different pathogens, a specific T cell profile was generated for each individual by monitoring the intracellular production of interferon-gamma by flow cytometry. This assay allows for the testing of multiple proteins or peptides at a single time and provides a quantitative and phenotypic assessment of CD4(+) and CD8(+) responding cells. We present profiling examples for several positive individuals, including those vaccinated with the smallpox and anthrax vaccines. We also show antigen optimization for the SARS-hCoV, as studies revealed that these proteins contain peptides which cross-react with more common coronaviruses, a cause of the common cold. The T cell array is an early and sensitive multiplex measure of active infection, exposure to a pathogen, or effective, recent vaccination.

Biological effects of a software-controlled voltage pulse generator (PhyBack PBK-2C) on the release of vascular endothelial growth factor (VEGF)

BACKGROUND

Electrical stimulation (ES) may induce vascular permeability and physiological angiogenesis. ES of rat muscles significantly increases the microvessel density and vascular endothelial growth factor (VEGF) protein levels. Thus, a pilot study was designed to analyze the effects of low-voltage electric impulses on VEGF levels in patients with dystrophic ulcers.

MATERIALS AND METHODS

Circulating VEGF levels were analyzed in 9 patients undergoing an ES session with low voltage software-controlled impulses applied through topical transducers (1-9 micros width, 1-420-Hz frequency and 30-120 V strength-100 microA max).

RESULTS

The session was accompanied by a peak of circulating VEGF (3-10 min from start) in all 9 patients, which was preceded by a rise of TNF-alpha (2-min) and was independently associated with soluble E-selectin levels. Nitric oxide generation was significantly improved on the day after treatment. No hemostatic activation or sustained inflammatory reaction were observed.

CONCLUSION

ES may represent a safe method for augmenting VEGF-mediated vascular protection, either directly or by induction of NO.

Direct oxidative DNA damage, apoptosis and radio sensitivity by spermine oxidase activities in mouse neuroblastoma cells

In mammals, the polyamines affect cell growth, differentiation, and apoptosis; their levels are increased in malignant and proliferating cells, thus justifying an interest in a chemotherapeutic approach to cancer. The flavoprotein SMO is the most recently characterized catabolic enzyme, preferentially oxidizing SPM to SPD, 3-aminopropanal and H(2)O(2). In this report, we describe a novel functional characterization of the recently cloned splice variant isoforms from mouse brain, encoding, among others, the nuclear co-localized spermine oxidase mSMOmu. The over-expression of the active isoforms mSMOalpha and mSMOmu, and the inactive mSMOdelta and mSMOgamma in mouse neuroblastoma cells, demonstrated the first evidence of the direct oxidative DNA damage by the SMO activities, either alone or, in a higher extent, when associated with radiation exposure, thus working as radio sensitizer. These effects were reverted by treatment with 50 muM and 100 muM doses of the inhibitor of SMO activity MDL 72,527. The over-expression of all SMO isoforms failed to influence the expression of the regulating enzymes of polyamines metabolism ODC and SSAT. Dealing with the unbalanced tissue specific SMO activities, these results could indicate a new direction to tailor chemotherapy-associated radiotherapy, improving dose-rate protocol and allowing the modulation of deleterious side effects on healthy tissues.

HLA-E up-regulation induced by HIV infection may directly contribute to CD94-mediated impairment of NK cells

Alterations in NK cell numbers and function have been repeatedly shown during HIV infection. In this study, NK cell number and MHC class I expression on CD4+ T cells were studied in HIV patients at different stages of disease progression. An increased expression of HLA-E was seen on CD4+ T cells. In parallel, a reduced number of CD94+ NK cells was observed in advanced disease stages. Moreover, a decline in CD94 expression on NK cells was observed at the HIV replication peak in patients undergoing antiretroviral treatment interruption, suggesting a role of viral replication on NK cells alterations. In vitro HIV infection induced a rapid down-regulation of HLA-A,B,C expression, paralleled by an increased expression of HLA-E surface molecules, the formal ligands of CD94 NK receptors. HIV-infected HLA-E expressing cells were able to inhibit NK cell cytotoxicity through HLA-E expression, since cytotoxicity was restored by antibody masking experiments. These data indicate that the CD94/HLA-E interaction may contribute to NK cell dysfunction in HIV infection, suggesting a role of HIV replication in this process.

CD1d expression by hepatocytes is a main restriction element for intrahepatic T-cell recognition

The liver has specific mechanisms to protect itself from infectious agents and to avoid autoimmunity, indicating an important role of the hepatic tissues in antigen presentation and tolerance induction. Since intrahepatic lymphocytes may contribute to the innate immunity and to the liver pathology, it is of interest to analyze the expression of antigen presenting molecules and of the related T cell recognition in liver, and how these change in relation to different diseases. We analyzed the expression of MHC class I, and of CD1-a, -b, -c, and -d proteins on liver tissues from patients with different hepatic diseases. Moreover, in the same patients we studied the intrahepatic and peripheral NKT cell recognition of alpha-galactosyl ceramide antigen in the context of CD1d. Unlike in other tissues, classical MHC class I molecules were poorly expressed in the hepatic compartment, suggesting that inflamed hepatocytes may trigger weak MHC-restricted T cell responses. Nevertheless, we observed a prevalent expression of HLA class I-like CD1d isoform on the hepatocyte surface, indicating that CD1d is the main restriction element in the liver. In patients with viral hepatitis, the intrahepatic CD1d expression parallels the recruitment of CD56+Valpha24Vbeta11+ NKT cells in the liver which recognize CD1d presenting glycolipids such as alpha-galactosyl ceramide, suggesting that the intrahepatic T cell immunity may focus on glycolipid antigens.

Activation of Fas receptor is required for the increased formation of the disialoganglioside GD3 in cultured cerebellar granule cells committed to apoptotic death

Apoptosis was induced in cultured cerebellar granule cells by lowering extracellular K+ concentrations (usually from 25 to 10 mM). The apoptotic phenotype was preceded by an early and transient increase in the intracellular levels of the disialoganglioside, GD3, which behaves as a putative pro-apoptotic factor. We examined whether activation of Fas receptor mediates the increase in GD3 formation in granule cells committed to die. Degenerating granule cells showed increased expression of both Fas receptor and its ligand (Fas-L), at times that coincided with the increase in GD3 levels and the induction of GD3 synthase mRNA. Addition of neutralizing anti-Fas-L antibodies reduced the extent of 'low-K+'-induced apoptosis and abolished the increase in GD3 levels and GD3 synthase mRNA. Similar reductions were observed in cultures prepared from gld or lpr mice, which harbor loss-of-function mutations of Fas-L and Fas receptor, respectively. In addition, exogenous application of soluble Fas-L further enhanced both the increase in GD3 formation and cell death in cultured granule cells switched from 25 into 10 mM K+. We conclude that activation of Fas receptor is entirely responsible for the increase in GD3 levels and contributes to the development of apoptosis by trophic deprivation in cultured cerebellar granule cells.

Correlation between tumor necrosis factor-alpha and d-dimer levels in non-small cell lung cancer patients

The present study was designed to investigate whether a correlation exists between IL-6, TNF-alpha and coagulation (Thrombin-antithrombin, TATc) or fibrinolysis (D-dimer) activation in non-small cell lung cancer (NSCLC) patients. One hundred thirty patients with NSCLC (n=65, 53 males, mean age 65 +/- 8, adenocarcinoma n=32, squamous cancer n=33) or chronic obstructive pulmonary disease (COPD) (n=65, 51 males, mean age 67 +/- 9) were studied. As control group 65 healthy donors (51 males, mean age 61 +/- 14) were also evaluated. The results obtained showed that median D-dimer levels were higher in NSCLC patients (3.0 microg/ml) compared either to COPD patients (1.1 microg/ml, P<0.05) or controls (0.3 microg/ml, P<0.0001). Positive TNF-alpha levels (>10 pg/ml) were found in 26% of NSCLC compared to 3% of COPD (P<0.002) and 5% of controls (P<0.0005). On the other hand, positive (>8.5 pg/ml) IL-6 levels were found in 53% of NSCLC and 21% of COPD patients, compared to 5% of control subjects (P<0.001). Median TATc levels were elevated in either NSCLC (6.9 microg/l) or COPD (5.7 microg/l) patients compared to controls (1.8 microg/l, P<0.0001). Elevated D-dimer levels were significantly associated to positive TNF-alpha levels in patients without distant metastasis (F=4.3, P<0.05). Moreover, TNF-alpha levels (P<0.01) were independently related to the presence of positive D-dimer levels in patients with non-metastatic NSCLC. These results suggest that increased levels of TNF-alpha might be responsible for an activation of fibrinolysis in patients with NSCLC.

[Radio-ulnar and radio-scaphoid-lunate arthrodesis in chronic polyarthritis. Clinical and radiologic follow-up of 32 cases]

INTRODUCTION

In 75% of all cases of rheumatoid arthritis the wrist is affected and in 12% is the region of initial manifestation of this chronic inflammatory joint disease. To prevent destruction of the wrist through carpal dislocation, radiolunate and radioscapholunate arthrodeses have increased in importance.

METHODS

During a 6.5-year period, 28 radiolunate and 4 radioscapholunate arthrodeses were performed in 30 patients. The indication for operation was progressive carpal translation and increasing subluxation of the wrist in which existent radiological damage had not reached more than grade III according to the classification of Larsen and co-workers.

RESULTS

The results obtained during the follow-up study (median: 17.3 months) showed in most treated patients after partial arthrodesis of the wrist no or fewer complaints concerning swelling and pain and an acceptable remaining range of motion of the wrist in everyday life. In patients with preoperatively existing ulnar deviation less than 15 degrees progressive carpal collapse and dislocation could be mostly prevented.

CONCLUSION

All told radiolunate and radioscapholunate arthrodeses successfully stabilized the wrist in patients suffering from rheumatoid arthritis.

[Postsurgical computed tomography of uncemented hip arthroplasty]

PURPOSE

Presentation of the value of postsurgical computed tomography (CT) to diagnose loosening of uncemented femoral stems.

MATERIALS AND METHODS

Incremental CT and spiral CT were performed on six femora with implanted uncemented stems after the entire femora were embedded in polymethylmethacrylate. The femora were subsequently sectioned (thickness 1 mm, separation 8 mm) and the medial and lateral contact areas of the prosthetic stem compared with the CT data.

RESULTS

The CT showed a contact of femoral stem and cortical bone between 0.4 mm (3.4 %) and 4.8 mm (47.1 %) and the section specimens between 0.9 mm (8.7 %) and 3.4 mm (36.7 %). No correlation was found between the results (r = 0.61), since the individual differences were up to 24 % in almost all sections.

CONCLUSIONS

Neither single-slice nor two-slice CT is capable of demonstrating the direct bone-endoprosthesis contact. Multidetector row CT (MDCT) is conceivably more accurate to measure the cortical contact of the femoral stem.

[Risk of recurrence following partial thyroidectomy for benign lesions. Report of 58 patients 15-25 years after surgery]

BACKGROUND

Since the 1980's, thanks to the introduction of new techniques and methods for the study of thyroid function, new light has been shed on certain aspects of thyroid disease that constitute the basis for surgical therapy. Multinodular goiter is a disorder affecting the entire gland, even when alterations mostly or exclusively involve a single lobe. The functional deficit resulting from partial or subtotal resection has a hypertophic/hyperplastic effect on the remaining parenchyma. Partial resections often lead to postoperative hypothyroidism, usually of a subclinical nature, which implies difficult management by means of replacement therapy.

METHODS

The authors report a series of 58 patients who underwent partial thyroidectomy to treat benign thyroid disease at the 2nd Surgical Department of the University of Florence during the period 1975-1985.

RESULTS

Of these patients, operated on more than 15 years ago, 36.2% - the majority of whom (87.5%) have constantly been on substitutive therapy using L-thyroxin - currently shows no alteration of the remaining parenchyma. Conversely, in 60.3% of the patients there was evidence of nodular/pseudonodular alterations; in this group, only 40% of the patients were on substitutive therapy. There seems to be no doubt that, with few exceptions, disease involving an apparently circumscribed area of the thyroid in reality affects the entire parenchyma.

CONCLUSIONS

Total thyroidectomy, therefore, represents the most appropriate treatment for multinodular goiter, even when the disease is limited to one lobe, thereby providing a cure for the disease and at the same time a state of euthyroidism easily achieved with the proper therapy.

Innate T-cell immunity in HIV infection: the role of Vgamma9Vdelta2 T lymphocytes

There is growing interest in the use of innate immune reactions in the therapy and prophylaxis of various diseases. Natural T (NT) lymphocytes that recognize infected cells or microbial compounds without the classical genetic restriction by polymorphic MHC molecules are crucial components of innate immunity. NT cells bearing the Vgamma9Vdelta2 T-cell receptor (TCR) are broadly reactive against intracellular pathogens, can lyse human immunodeficiency virus (HIV) infected cells, and release cytokines capable of regulating HIV replication. The potent antiviral activities of Vgamma9Vdelta2 T cells may help to contain viral spread during acute HIV infection and/or to prevent the establishment of viral persistence. Substantial changes in the composition and function of circulating gammadelta T-cell pools occur in HIV-infected patients. These changes a) may contribute to the etiopathogenesis of opportunistic infections and neoplasms, and b) are partly reversed by highly active anti-retroviral therapy (HAART). In addition to direct antiviral activities, activated gammadelta T cells influence dendritic cell maturation and the adaptive alphabeta T-cell response. Vgamma9Vdelta2 T cells can be stimulated in vivo and in vitro by various nonpeptidic antigens (NpAgs) and recent animal experimental data suggest that activated Vgamma9Vdelta2 T cells may help to control SIV replication. Currently, NpAgs are being assessed as potential therapeutic agents in AIDS, tuberculosis and certain cancers susceptible to Vgamma9Vdelta2 T-cell effector mechanisms.

Involvement of GD3 in platelet activation. A novel association with Fcgamma receptor

Gangliosides are sialic acid-containing glycosphingolipids present in the outer leaflet of the plasma membrane of many cell types where they modulate adhesive processes. The main population of glycolipids in resting platelets is represented by ganglioside M3 (GM3). It has been demonstrated that following platelet activation ganglioside D3 (GD3) is rapidly formed from the GM3 pool. The present study was designed to evaluate the link between platelet activation and GD3 expression and to verify whether this ganglioside might play a role in modulating signal transduction events. Our results suggest that following platelet activation, GD3 is rapidly expressed on the platelet surface and internalised to the cytoskeleton where it transiently associates first with the Src family tyrosine kinase Lyn then with the Fc receptor gamma chain. This sequence of events ultimately leads to an enhanced CD32 (the Fc receptor isoform present in platelets) expression on the platelet membrane. These data drive us to speculate that GD3 might act as second messenger in the activatory cascade, which leads to CD32 expression and triggers platelet adhesion and spreading to the subendothelial matrix.

An early increase in the disialoganglioside GD3 contributes to the development of neuronal apoptosis in culture

We induced apoptosis in primary cultures of cerebellar granule neurons by switching the growing medium into a medium containing lower concentrations of K(+) (5 or 10 mM instead of 25 mM) or, alternatively, by addition of staurosporine. The apoptotic phenotype was always preceded by an early increase in the intracellular levels of the disialoganglioside GD3, which peaked at 2-6 h and returned back to normal at 12 h. GD3 synthase, the enzyme that forms GD3 from the monosialoganglioside GM3, was also induced at early times after the induction of apoptosis in granule cells. Immunofluorescent staining showed that GD3 increased in neuronal cell bodies and neurites, but was never localized in cell nuclei. In cultures switched into a low K(+)-containing medium, exogenously applied GD3, but not the disialoganglioside GD1a, accelerated the development of neuronal apoptosis. In contrast, the antisense-induced knock-down of GD3 synthase was protective against granule cell death induced by lowering extracellular K(+) from 25 to 10 - but not 5 - mM. These results demonstrate that an early and transient increase in GD3 synthesis is one of the factors that contribute to the induction of neuronal apoptosis in culture.

Cancer testis antigens expression in mesothelioma: role of DNA methylation and bioimmunotherapeutic implications

Recent evidences suggest that malignant mesothelioma may be sensitive to immunotherapy; however, little is known about malignant mesothelioma-associated tumour antigens. Focusing on cancer/testis antigens, the expression of well-characterised immunogenic tumour-associated antigens was investigated in malignant mesothelioma cells. At variance with MAGE-4 and NY-ESO-1, malignant mesothelioma cells frequently expressed MAGE-1, -2 and -3, GAGE 1-2, GAGE 1-6, SSX-2 and SSX 1-5, and distinct malignant mesothelioma cells concomitantly expressed at least four cancer/testis antigens. Additionally, the tumour-associated antigens RAGE-1 was expressed at high levels in both benign and malignant mesothelial cells. Lastly, treatment with the DNA hypomethylating agent 5-aza-2'-deoxycytidine induced and up-regulated the expression of the cancer/testis antigen examined in malignant mesothelioma cells. Overall, these findings strongly suggest that cancer/testis antigens-based immunotherapy may represent a suitable therapeutic approach to malignant mesothelioma, and foresee the clinical use of 5-aza-2'-deoxycytidine to design new chemo-immunotherapeutic strategies in malignant mesothelioma patients.

[Ultrasound diagnosis of inflammatory diseases of the hand and elbow]

After clinical and radiological examination, ultrasound has an important place in the diagnostic procedures for patients with chronic inflammatory diseases. Synovitis and effusion of the joint can be documented. Sonography may be helpful in providing an earlier diagnosis. Erosive lesions of the articular surface in the sonographic field of view can be detected at a very early stage, often when the clinical and radiological examinations are still unremarkable. This may lead to an earlier start of drug therapy or an earlier indication for operative treatment. Sonography gives a good impression of the inflammatory changes of the elbow joint and the distribution of synovitis and joint effusion in the different parts of the joint. It is a good method to document the therapeutic effects. The sonographic echogenicity of the muscle of rheumatoid patients seems to change. Synovitis and effusion of the hand can be documented with ultrasound. Infiltration of the synovitis into the tendon could not be visualized. The sonographic diagnostic accuracy in tendon ruptures of the hand was reduced in comparison with the clinical examination. Whether ultrasound will be an efficient method to identify patients at risk for a tendon rupture will be seen with further developments of the technical possibilities.

Soluble selectin levels in patients with lung cancer

Increased expression of selectins has been found on endothelial cells of venules and capillaries in the tumor stroma of non-small cell lung cancer, suggesting their functional role in the process of chemotaxis for tumor cells. The present study was aimed at analyzing the role of both soluble (s)P-selectin and sE-selectin levels in association with clinico-pathological variables in 116 patients with lung cancer, 38 patients with benign diseases and 59 healthy donors. The results obtained showed that sP-selectin and sE-selectin levels were higher in patients with lung cancer compared to normal donors (p<0.02 and p<0.005, respectively). No differences were observed among patients with various benign diseases for both selectins. Increased levels of sP-selectin and sE-selectin were significantly associated with squamous lung cancer at late stages (p<0.05), but not adenocarcinoma. Both sP- and sE-selectin were independently related to the stage of squamous lung cancer by stepwise regression analysis (p<0.02 and p<0.03, respectively), while only sE-selectin was independently related to the presence of distant metastasis in the same histotype (p<0.02). These results suggest that measurement of plasma soluble selectins might represent a useful laboratory parameter in the management of patients with squamous lung cancer.

The use of a personal digital assistant for wireless entry of data into a database via the Internet

BACKGROUND

Researchers typically record data on a worksheet and at some later time enter it into the database. Wireless data entry and retrieval using a personal digital assistant (PDA) at the site of patient contact can simplify this process and improve efficiency.

METHODS

A surgeon and a nurse coordinator provided the content for the database. The computer programmer created the database, placed the pages of the database on the PDA screen, and researched and installed security measures.

RESULTS

Designing the database took 6 months. Meeting Health Insurance Portability and Accountability Act of 1996 (HIPAA) requirements for patient confidentiality, satisfying institutional Information Services requirements, and ensuring connectivity required an additional 8 months before the functional system was complete.

CONCLUSIONS

It is now possible to achieve wireless entry and retrieval of data using a PDA. Potential advantages include collection and entry of data at the same time, easy entry of data from multiple sites, and retrieval of data at the patient's bedside.

Effects of mud-pack treatment on plasma cytokine and soluble adhesion molecule levels in healthy volunteers

BACKGROUND

The suggested hypothesis of a direct anti-inflammatory property of mud-pack treatment has led us to speculate that its action on the cytokine network might counteract the heat-stress-related effects on platelet and endothelial cell function often reported following hot-spring baths. Therefore, the present study was designed to investigate the effects of a cycle of 12 daily mud-pack treatments on bio-humoral markers of inflammation, as well as on markers of in vivo platelet and/or endothelial cell activation, in plasma samples obtained from healthy volunteers.

METHODS

Blood samples were obtained before (T(0)), at the end of the first treatment (T(1)) and after a cycle of 12 daily mud-pack treatments (T(2)). Plasma cytokines (TNF-alpha IL-1beta, and IL-6) and adhesion molecules (sP-selectin, sE-selectin and sVCAM) levels, as well as hematocrit and complete and differential blood cell counts were determined at every time point.

RESULTS

Plasma sP-selectin levels were not modified during treatment, as were not sE-selectin or sVCAM. Similarly, IL-1beta and TNF-alpha levels were unchanged through a 12 daily mud-pack treatment. Conversely, plasma IL-6 levels were significantly lowered at the end of a 20-min 47 degrees C mud-pack treatment (p<0.01).

CONCLUSIONS

The lack of effects on in vivo platelet and/or endothelial cell activation suggests that hot mud-pack treatment might be used as a relatively safe procedure in patients with atherothrombotic disorders.

[Optimized polymethyl methacrylate-embedding enables exact section examination of the femur with an uncemented femoral stem]

AIM

Embedding of larger bones, as described in this article, is not possible without marked modifications of the methods followed for small, undecalcified bone specimens. Problems such as turbidity of the PMMA, incomplete hardening of the medullary cavity due to insufficient infiltration and, especially, uncontrolled polymerization with excessive bubbling make analysis of the specimens impossible. Thus, modifications with respect to the infiltration times in the individual solutions, the benzoyl peroxide quantities added and the temperature during the polymerization phase were undertaken.

METHOD

The infiltrations were performed under vacuum. A cooling circulation was created in a standard water bath with a circulator pump to facilitate extraction of the polymerization heat. The use of PMMA blocks as filling material and polymerization inductors was especially important.

RESULTS

There was no turbidity or excessive bubbling of the PMMA in any of the specimens embedded with this method. Analysis of the sections showed a low-bubble medullary cavity with 01 bubble/cm(2). Up to 10 bubbles/cm(2) were observed only in the large cancellous space in the trochanteric region over a length of 56 cm. All bubbles were a maximum of 1.5 mm in size.

CONCLUSION

With the described method it is possible to embed large bones in PMMA.

SV40 replication in human mesothelial cells induces HGF/Met receptor activation: a model for viral-related carcinogenesis of human malignant mesothelioma

Recent studies suggested that simian virus 40 (SV40) may cause malignant mesothelioma, although the pathogenic mechanism is unclear. We found that in SV40-positive malignant mesothelioma cells, the hepatocyte growth factor (HGF) receptor (Met) was activated. In human mesothelial cells (HMC) transfected with full-length SV40 DNA (SV40-HMC), Met receptor activation was associated with S-phase entry, acquisition of a fibroblastoid morphology, and the assembly of viral particles. Coculture experiments revealed the ability of SV40-HMC to infect permissive monkey cells (CV-1), HMC, and murine BNL CL cells. Cocultured human and murine SV40-positive cells expressed HGF, showed Met tyrosine phosphorylation and S-phase entry, and acquired a spindle-shaped morphology (spBNL), whereas CV-1 cells were lysed. Cocultured HMC inherited from SV40-HMC the infectivity, as they induced lysis in cocultured CV-1 cells. Treatment with suramin or HGF-blocking antibodies inhibited Met tyrosine phosphorylation in all large T antigen (Tag)-positive cells and reverted the spindle-shaped morphology of spBNL. This finding indicated that Met activation and subsequent biological effects were mediated by an autocrine HGF circuit. This, in turn, was causally related to Tag expression, being induced by transfection with the SV40 early region alone. Our findings suggest that when SV40 infects HMC it causes Met activation via an autocrine loop. Furthermore, SV40 replicates in HMC and infects the adjacent HMC, inducing an HGF-dependent Met activation and cell-cycle progression into S phase. This may explain how a limited number of SV40-positive cells may be sufficient to direct noninfected HMC toward malignant transformation.

Reciprocal strength ratio in shoulder abduction/adduction in sports and daily living

PURPOSE

Functionally, the shoulder is considered a ball joint, whereby high mobility is attended by low stability. Therefore, muscular balance is decisive for stability. Altered strength ratios are frequently described as "muscular dysbalances" and considered one of the causes of shoulder pathologies, whereby objective quantification is difficult.

METHODS

In order to quantify physiological muscle balance, the strength ratio of shoulder abduction/adduction (AB/AD) was determined in 166 untrained men (UM) concentrically at 60 degrees.s-1 (LIDO-Active). The influence on this norm of one-sided (25 high-performance (TPH), 18 leisure tennis players (TPL)) and two-sided athletic exercise (32 gymnasts (GY)), altered daily exercise (11 paraplegics with paralysis time < 4 months (PP), 11 paraplegics with paralysis time > 2 yr (PU)), and a combination of altered daily exercise and athletic activity (16 trained paraplegics (PT)) was examined (ANOVA, alpha = 0.05).

RESULTS

Determination of the AB/AD quotient in UM was 0.82. Shoulder stress in sports led to a decrease in quotients compared with UM because of a relatively increased torque in AD (P < 0.01). At the beginning of a paraplegia, the quotient of AB/AD is elevated (P < 0.05). This altered ratio decreases with duration of paralysis (PU) and athletic activity (PT).

CONCLUSION

With increased shoulder stress, the altered strength ratios reflect specific requirements of the performance attained. However, the importance of muscular dysbalances for the onset of shoulder complaints must be considered more important than their influence on athletic performance capacity.

Increased soluble P-selectin levels in hepatitis C virus-related chronic hepatitis: correlation with viral load

BACKGROUND

Platelet functional abnormalities are commonly found in patients with chronic liver disease; however, their nature and clinical significance are still a matter of discussion.

METHODS

Soluble P-selectin (sP-selectin, a marker of in vivo platelet activation) levels, lipid pattern, and clotting activity were investigated in 39 patients with histologically confirmed chronic C hepatitis.

RESULTS

Serum factor VIIc (P < 0.01), total cholesterol (P < 0.005), high density lipoprotein (P < 0.001), and low density lipoprotein (P<0.05) levels were lower in patients compared with healthy subjects, whereas triglyceride and fibrinogen levels were similar in both groups. Platelet counts were lower in chronic hepatitis patients compared with controls (P < 0.0001), and approximately 20% of patients had thrombocytopenia (platelet counts < 110 x 10(3)/microL). Platelet-associated immunoglobulin G (PAIgG) was present in 30.8% of patients. Plasma sP-selectin levels were higher in hepatitis C patients compared with controls (P < 0.0001), and significant differences were observed with respect to the Scheuer score (P < 0.01). The analysis of the distribution of plasma sP-selectin showed the presence of higher levels in patients with low platelet counts compared with patients with normal platelet counts and controls (P < 0.0001); moreover, sP-selectin levels did not correlate with the presence of PAIgG. On the other hand, sP-selectin levels directly correlated with serum hepatitis C virus (HCV)-RNA (P < 0.05) and inversely correlated with platelet count, blood lipids, and factor VIIc.

CONCLUSIONS

The results obtained in this study support the hypothesis that HCV infection might be directly responsible for a condition of in vivo platelet activation in patients with chronic C hepatitis.

Effects of isolated limb perfusion with tumor necrosis factor-alpha on circulating levels of proinflammatory cytokines

Hyperthermic isolated limb perfusion (ILP) with tumor necrosis factor-a (TNFalpha) and cytotoxic drugs is currently used for treatment of melanoma and sarcoma of the limbs. Tumor necrosis factor-alpha is involved in the systemic inflammatory response syndrome as a result of activation of inflammatory cells and production of bioactive substances. The goal of this study was to determine the circulating levels of proinflammatory cytokines and soluble adhesion molecules in 19 patients with limb melanoma or sarcoma undergoing ILP with (n = 9) or without TNFalpha (n = 10). The results obtained demonstrated that ILP with TNFalpha was responsible for a leakage of TNFalpha in the systemic circulation, followed by a rise in interleukin (IL)-6 and IL-8 levels within I h. Elevated soluble (s)P-selectin levels were found 1-3 h after ILP. Plasma sE-selectin peaked 6-9 h after ILP, and soluble vascular cell adhesion molecule (sVCAM) levels reached a maximum after 24 h. Significant correlations were observed among these variables, confirming the interdependence of all changes observed. On the other hand, ILP with cytotoxic drugs alone induced only a modest release of TNFalpha, which was not followed by an immediate rise in IL-6 and IL-8. Four of the 9 patients undergoing ILP with TNF had severe systemic toxicity. No association was found between systemic TNF levels and the clinical outcome, whereas elevated TNF perfusion levels as well as systemic IL-6 and IL-8 levels were constantly elevated in patients with severe toxicity. These results are suggestive of an important role of TNFalpha levels in the perfusion system (more than leakage of perfusate) in causing postoperative toxicity, although other ILP-related factors should not be excluded.

[Quantification of position-related errors in measurement of antetorsion of the femur with computerized tomography--introduction of a method for positional correction]

OBJECTIVE

To quantify the influence of patient positioning on the determination of collodiaphyseal (CCD) angle and femoral neck anteversion based on computed tomography. Description of a method for positional correction.

METHODS

We evaluated the CT scans of 84 femora from 77 patients, who received individually adapted prostheses. Projected as well as real anteversion and CCD angles were determined and corrected for positioning errors using a newly proposed mathematical method, and compared to other evaluation methods.

RESULTS AND CONCLUSIONS

We determined an average tilt of 4.2 degrees in the sagittal and of 9 degrees in the coronary plane, which correlated definitely with the deviations found in the graphical determination of the projected anteversion angle. This produced measurement errors of the projected anteversion angle of up to 10 degrees. Mathematically independent angles, such as projected anteversion and real CCD angle, showed only a weak correlation. This indicates also an anatomical independence of these angles.

Antiviral activity and anergy of gammadeltaT lymphocytes in cord blood and immuno-compromised host

Gammadelta T lymphocytes recognize nonpeptidic microbial antigens without MHC restriction and display both lytic and proliferative responses to human immunodeficiency virus (HIV)-infected cells. This innate recognition involves both T Cell Receptor (TCR) and NK-receptor mediated signalling through non-peptidic metabolites and HLA class I down-regulation. We observed that HLA-masking and nonpeptidic phosphoantigens induce the expression of CD25 and CD69 activation markers on the surface of gammadelta T cells. Interestingly, CD94+ cell depletion by magnetic beads showed that the expression of this antigen is essential for Vdelta2 T cell activation by HLA-masking. Moreover, both phosphoantigen-stimulation and in vitro HIV infection resulted in marked Vgamma9Vdelta2 T cell expansion, whereas HLA-masking was unable to induce proliferative responses. Finally, we observed a relevant hyporesponsiveness to non-peptidic antigens in HIV-infected persons and in cord blood cells from healthy donors when compared to adult PBMC from uninfected donors. Altogether, the reduced ability to naturally recognize the infected cells may contribute to HIV-disease progression and may facilitate maternal transmission of HIV infections.

New ultrasonically prepared Co-based catalysts for Fischer-Tropsch synthesis

An extensive study of different preparation methods for Co/SiO2 catalysts is reported in this paper. In addition to the conventional impregnation, other more innovative methods are used including ultrasound. The prepared samples are fully characterized and tested in the CO hydrogenation (Fischer-Tropsch synthesis). The best catalytic performance, both as CO conversion and hydrocarbons selectivity, is shown by one of the sample prepared using ultrasound.