Fusion of the distal sesamoid and distal phalanx in a yearling colt

This paper describes a rare malformation of the distal portion of the left foredigit of a 15-month-old half-bred colt which was severely lame. Radiological, pathological and tomographic studies revealed hypoplasia of the metacarpophalangeal skeleton, absence of the distal sesamoid and deformation of the distal phalanx. Morphological analysis of the lesion and computerised measurement of the width of the articular surface of the distal phalanx suggested an early fusion between the distal sesamoid and distal phalanx.

Recombinant wheat antifungal PR4 proteins expressed in Escherichia coli

PR proteins are soluble and host-coded molecules with antifungal activity induced by a variety of agents. Wheat contains several PR proteins and among them are those of the class 4 coded wheatwin1 and wheatwin2; the two native proteins have been isolated from wheat kernel and the coding cDNA clones have been recently characterized. Herein, we report the expression of recombinant wheatwin1 and wheatwin2 in Escherichia coli-insoluble fractions; a new protocol for the purification in high yields and correct processing of the two proteins was developed. The recombinant proteins have molecular weights identical to that of the native proteins, indicating that the removal of the N-terminal methionine and cyclization of glutamine to pyroglutamate was complete. Both recombinant proteins inhibited in vitro the growth of Fusarium culmorum exhibiting antifungal properties similar to those of the native proteins.

A basic peroxidase from wheat kernel with antifungal activity

A basic heme-peroxidase (WP1) was purified to homogeneity from wheat (Triticum aestivum) kernels. The protein was not glycosylated and exhibited a molecular mass of 36 kDa and a pI of 8.0. The N-terminal amino acid sequence revealed a very high similarity with a wheat flour peroxidase allergen associated with baker's asthma. WPI showed indole-3-acetic acid oxidase activity in the presence of Mn2+ and phenolic cofactors. Antifungal assays performed in vitro towards phytopathogenic fungi indicated that WP1 was active in inhibiting germ tube elongation. This first report on antifungal properties of a heme-peroxidase gives experimental support to the idea that peroxidases play a defensive role against invading pathogens.

Experimental trichinellosis in fallow-deer (Dama dama L.)

Herbivora can play a very important role in spreading trichinellosis, as showed by the massive epidemics in man, caused by the consumption of horse meat in the last years. In this context, the present study has been undertaken to verify, through an experimental infection, the susceptibility, together with other biological parameters, of fallow-deer to Trichinella infection. The four animals, 8-9 months of age and 18-25 Kg body weight, were orally infected with low doses of Trichinella britovi and T. pseudospiralis (2,000 larvae/animal). After day 30 p.i., the animals were necropsied and, using artificial digestion methods, larval burden of Trichinella in muscle tissues was determined. Histopathological, serological (IgG monoclonal blocking ELISA) and biochemical data were assessed during the experiment. The results showed the susceptibility of fallow-deer to T. britovi and T. pseudospiralis infection; under the same inoculum size, the number of larvae/g was higher in group infected with T. britovi. The animals showed a higher immunological response to T. pseudospiralis infection. The results are discussed.

Susceptibility of nutria (Myocastor coypus) to Trichinella infection: biological aspects

Experimental infections with three different species of Trichinella in nutria in order to evaluate the susceptibility and the role of these rodents in the spreading of parasitosis in nature were carried out. The nutria is present in many italian wet areas and its distribution is expanding. The nutria meat is utilized as food in different countries and is retained responsible for trichinellosis in man. Two groups of ten animals were infected per os with 500 and 5,000 (n. 10) infective larvae of T. britovi; an additional study was arranged with two groups of animals infected with 5,000 larvae of T. spiralis and T. pseudospiralis, respectively. After 45 days, all animals were slaughtered and samples of different muscles were processed by standard artificial digestion and by routine histological methods. Serological investigations (specific IgG) have been carried out on sera samples by employing a monoclonal blocking ELISA. The animals showed a significant susceptibility to the infection with all species of tested Trichinella and immunological reactivity. Data obtained are discussed.

Isolation and amino acid sequence of two new PR-4 proteins from wheat

We have purified and characterized two new pathogenesis-related (PR) proteins from wheat belonging to the PR-4 family. We named the proteins wheatwin3 and wheatwin4 in analogy with the previously characterized wheatwin1 and wheatwin2. Their isoelectric points were 7.1 and 8.4, respectively. We determined the complete amino acid sequence of both proteins by a rapid approach based on the knowledge of the primary structures of the homologous wheatwin1 and wheatwin2. Wheatwin3 differs from wheatwin1 in one substitution at position 88, while wheatwin4 differs from wheatwin2 in one substitution at position 78. The secondary structure and solvent accessibility of these residues were determined on the three-dimensional model of wheatwinl. Residue 88 was very accessible and was located in a flexible region. Preliminary results indicate that, like wheatwin1 and wheatwin2, wheatwin3 and wheatwin4 have antifungal activity.

Near infrared spectroscopic assessment of hemodynamic changes in the early post-burn period

Near infrared reflectance spectroscopy and imaging was used to assess non-invasively the hemodynamic changes that occur in the early post-burn period in cutaneous burn injuries of varying depth. An acute porcine model was used to demonstrate the potential of near infrared spectroscopy and imaging to accurately determine the change in tissue oxygenation, blood volume and tissue water content following a thermal injury. Near infrared spectroscopy was used to monitor tissue at discrete locations, while spectroscopic imaging was able to survey large areas of tissue. Both methods were rapid and non-invasive. Tissue hemoglobin oxygen saturation, total hemoglobin and tissue water content were all affected by thermal injury and changed significantly over a 3 h post-burn monitoring period. Burns that ranged in severity between superficial and full thickness displayed a significantly different hemodynamic response. When the early post-burn profiles (1-3 h) of tissue hemoglobin oxygen saturation, total hemoglobin and tissue water content were considered jointly, injuries leading to superficial, intermediate partial thickness, deep partial thickness and full thickness burns could all be differentiated at high statistical significance. These results suggest that non-invasive hemodynamic monitoring in the early post-burn period using near infrared spectroscopy may be of value in the early assessment of burn injury.

Isolation and characterisation of wheat cDNA clones encoding PR4 proteins

Two cDNA clones encoding the previously characterised PR4 proteins wheatwin 1 and wheatwin2 from wheat (Triticum aestivum cv. S. Pastore) have been identified and named wPR4a and wPR4b, respectively. The clones have been isolated by screening a cDNA library with a specific cDNA probe obtained by RT-PCR. The wPR4a and wPR4b cDNAs contain open reading frames of 441 and 447 bp that encode for wheatwin1 and wheatwin2, respectively.

Radiation protection in radioguided surgery of breast cancer

The protocols for sentinel lymph node biopsy and radioguided occult lesion localization could potentially be of great value in the management of breast cancer patients. Both involve the injection of a 99Tcm-labelled radiopharmaceutical close to or into the lesion, localization of the sentinel lymph node or occult lesion by scintigraphy, and surgical removal with the aid of a hand-held gamma-ray detector. We present dosimetric data on patients and hospital personnel involved in these procedures. For evaluation of radiation protection, we measured the absorbed dose and air kerma rate. Activity levels in excised tissues and surgical instruments were also determined. For patients, the mean absorbed dose to the abdomen was 0.45 mGy, which is low compared to doses received from other diagnostic examinations. For surgeons after 100 operations, the mean absorbed dose to the hands was 0.45 mGy and the mean effective dose 0.09 mSv. Absorbed doses to all hospital personnel involved in the procedures were very low compared to recommended annual limits stipulated by the International Commission on Radiological Protection. We conclude that these procedures, performed according to protocols laid down by the European Institute of Oncology, Milan, are safe from the point of view of radiological protection and that only routine precautions are necessary.

Probing the modelled structure of wheatwin1 by controlled proteolysis and sequence analysis of unfractionated digestion mixtures

We set up a method to get rapid information on the three-dimensional structure of peptide and proteins of known sequence. Both native and alkylated polypeptide is hydrolyzed with a number of proteases at different digestion times and the resulting mixtures are compared by HPLC analysis to establish the differences in the hydrolysis pathways of the folded and unfolded molecule. Then, the unfractionated digestion mixtures of the native polypeptide are submitted to automatic sequence analysis to identify the hydrolysis sites. The sequence of each fragment present in the mixtures is reconstructed and its amount determined by quantitative data of the sequence analyses. We used this approach to determine the amino acid surface accessibility of wheatwin1, a pathogenesis-related protein from wheat, and constructed a predictive three-dimensional model based on the knowledge of the tertiary structure of barwin, a highly homologous protein from barley. The procedure allowed us to quickly identify and quantify the hydrolysis at the susceptible bonds which could be classified as exposed, partially hidden, or inaccessible. The results were useful to evidentiate and discuss concordances and differences between experimental and model predicted accessibilities of amino acid residues. Proteins 1999;36:192-204.

Relationship between the shape and size of radiofrequency induced thermal lesions and hepatic vascularization

AIMS AND BACKGROUND

The aim of this study was to evaluate the relationship between hepatic vascularisation and the final size and shape of radiofrequency (RF) induced thermal lesions.

METHODS

Series of four RF thermal lesions were created in explanted calf livers and in pig livers maintaining the following experimental conditions throughout the procedure: normal hepatic perfusion, occlusion of the hepatic artery, occlusion of the portal vein, occlusion of both hepatic artery and portal vein (Pringle maneuver) and subtotal occlusion of the hepatic veins. A 14G expandable needle electrode was used to make the thermal lesions. Each lesion was created applying predetermined temperatures ranging between 95 and 115 degrees C and an exposure time of 20 minutes.

RESULTS

Occlusion of the hepatic artery during the RF procedure resulted in moderate and not significant increases in thermal lesion diameter compared with those obtained in normally perfused liver (3.0 +/- 0.4 cm vs 3.0 +/- 0.2 cm), while occlusion of the portal vein resulted in larger lesion diameters (3.5 +/- 0.3 cm). In both these cases the diameters of the thermal lesions were smaller than those obtained in explanted calf liver (4.0 +/- 0.3 cm) and their shape showed peripheral irregularities. Thermal lesions larger than those seen in normally perfused liver and equaling those observed in explanted calf liver were created both during the Pringle maneuver (4.0 +/- 0.2 cm) and after subtotal occlusion of the hepatic veins (4.0 +/- 0.3 cm). In both these cases the thermal lesions were regular in shape.

CONCLUSIONS

Occlusion of the blood flow during the RF procedure avoids heat loss by convection, resulting in the creation of larger thermal lesions than those obtained in normally vascularized liver using the same electrode, temperatures and exposure time. This technique could therefore be employed in humans to destroy large hepatic tumor nodules.

[Radiation protection in the use of tracers in radioguided breast surgery]

PURPOSE

Recent techniques in nuclear medicine have permitted to implement new procedures useful in surgery. Among these, the procedures for locating sentinel lymph nodes and nonpalpable breast lesions are of great interest. The protocols for the location of the sentinel lymph node and for the radioguided location of occult lesions developed at the European Institute of Oncology (IEO, Milan) are based on the administration of radiopharmaceuticals labelled with Technetium-99m (99mTc). We evaluated the dosimetric data relative to patients and hospital personnel to assess whether specific radiation protection procedures are needed.

MATERIAL AND METHODS

Fifty patients with nonpalpable breast lesions and 50 patients with suspected lymph node involvement were enrolled in this study. All the patients underwent surgery the day after in-loco administration of the radiopharmaceutical (11 MBq of 99mTc). The absorbed dose to the hospital personnel was estimated from the air kerma rate measured by ionization chamber at different distances from the patients at 0 and 16 hours after the radiopharmaceutical administration. In order to evaluate radiation protection for patients, absorbed doses were measured positioning thermoluminescent dosimeters on the patient's skin for about 16 hours. In the operating room, activity was measured on some excised tissues (lymph nodes and tumors) and on surgical instruments.

RESULTS

Absorbed doses were very low for the clinical staff also in case of prolonged patient assistance. After 100 cases, the surgeon mean absorbed dose to the hands and mean effective dose were .45 mGy and .09 mGy, respectively. These values correspond to 1% of the annual dose limit to the hands and to 10% of the annual equivalent effective dose recommended for the population (ICRP 60 and law by decree 230/95). The absorbed dose to healthy tissues of the patients were lower than 1 mGy (mean values: contralateral breast: .9 mGy; abdomen .45 mGy). The mean activity detected in the excised tissues was 9 kBq and 900 kBq in the sentinel lymph nodes and in the tumor lesions (injection site), respectively. The activity detected on the surgical instruments, higher on gauzes (< 100 kBq), was negligible.

CONCLUSIONS

From the radiation protection point of view, the data support the validity of our protocols. Absorbed doses to the hospital personnel are low and require neither a radiation protection control nor a classification of exposed workers as classes A or B. Special containers for radioactive wastes are necessary in the administration room but not in the operating room, where the levels of possible contamination are negligible.

Sentinel node localization in cutaneous melanoma: lymphoscintigraphy with colloids and antibody fragments versus blue dye mapping

In stage I cutaneous melanoma, biopsy of the first tumour-draining lymph node (sentinel node, SN) may replace routine elective lymph node dissection (ELND). The patent blue dye (PBD) technique has been shown to be an original method for the localization of the SN, but its sensitivity is sometimes unsatisfactory, depending on the basin where the SN is located. We compared three methods to locate the SN: intraoperative PBD mapping, lymphoscintigraphy (LS) with an aspecific tracer (colloid) and LS with a specific tracer (monoclonal antibody, MoAb). Fifty patients with cutaneous melanoma were enrolled in this study. The day before surgery LS was performed following an intradermal injection of 55 MBq technetium-99m-labelled HSA colloidal particles (25 patients: group A) or 220 MBq of 99mTc-F(ab')2 MoAb 225.28 S (25 patients: group B) around the site of the primary lesion. In group B an equal amount of tracer was injected, as a control, in the contralateral site. Early and delayed images were acquired with a gamma camera and SN(s) marked on the skin. In all 50 patients the PBD technique was also performed immediately before surgery. When a blue node was identified intraoperatively, its radioactivity level was measured with a gamma probe. In the absence of blue coloration, the probe alone was used to detect the SN. Lymphoscintigraphic visualization of SNs was possible in 50/50 patients (100%), a total of 73 SNs (38 in group A and 35 in group B) were found, distributed in 55 basins. Gamma probe detection (GPD) allowed the identification of SNs in 49/50 patients (98%), and 72 SNs in 54 basins were localized. By contrast, using PBD, SNs were stained only in 40/50 patients (50 SNs in 40 basins). A tumour-positive SN was histologically proven in 13 patients (26%). In group B, no increase uptake was observed in the seven positive SNs (6/25 patients) compared with the contralateral uninvolved nodes. In conclusion this study demonstrates that LS combined with GPD is a safe method for detecting SNs and is more sensitive than the PBD technique. The use of MoAb fragments did not show any advantage over the non-specific tracer.

Collagen fibril arrangement and size distribution in monkey oral mucosa

Collagen fibre organisation and fibril size were studied in the buccal gingival and hard palate mucosa of Macacus rhesus monkey. Light and electron microscopy analysis showed connective papillae exhibiting a similar inner structure in the different areas examined, but varying in distribution, shape and size. Moving from the deep to surface layers of the buccal gingival mucosa (free and attached portions), large collagen fibril bundles became smaller and progressively more wavy with decreasing collagen fibril diameter. This gradual diameter decrease did not occur in the hard palate mucosa (free portion, rugae and interrugal regions) where the fibril diameter remained constant. A link between collagen fibril diameter and mechanical function is discussed.

Reimplantation of the upper limb after tear lesion: long-term results

Reimplantation revascularization of the upper limb proximal to the elbow represents an absolute indication in specific conditions. In the young subject, in good general conditions with a clean amputation (guillotine-like caused by a circular saw), the limb preserved in ideal conditions, indications for reimplantation are supported by the expectations of good functional recovery. When amputation is due to avulsion tear the possibility of anatomical and functional success is influenced by the complexity of vascular and nervous lesions. Thus, indications for reimplantation must be made by carefully evaluating each individual case.

Acquisition protocol for breast cancer imaging with technetium-99m-labeled synthetic peptide and technetium-99m-MDP

Technetium-99m-MDP and, recently, a 99mTc-labeled synthetic decapentapeptide have been shown to localize in breast lesions. Our goal was to develop an acquisition protocol to improve image quality, to improve detection of axillary lymph nodes with disease and to compare the utility of the new radiotracer to 99mTc-MDP.

METHODS

Ninety-three patients with documented breast carcinoma were studied. Thirty-eight patients were studied in the supine position with anterior and lateral views: eight patients were injected intravenously with 600-740 MBq 99mTc-EPPT and 30 patients with the same activity of 99mTc-MDP. A second group of 55 patients was studied using the same total activity: 20 patients were injected with 99mTc-EPPT and 35 patients with 99mTc-MDP. To improve results, patients were positioned standing up with their arm raised. The breast with a marker over the nipple touched the collimator in the oblique-lateral position. Early planar images (2-5 min postinjection) were acquired with this positioning for the healthy and the tumor breast, collecting 1500 K counts in a 256 x 256 matrix. Imaging of the axillary regions was performed while the patients were positioned supine and a frontal image was obtained at 10-15 min postinjection for 1800 K counts.

RESULTS

This diagnostic study produced good quality images, with the breast lesions and axilla visualized. The positions had limitations due to the overlapping of other organs and to the proximity with the chest wall.

CONCLUSION

Using this protocol, all primary lesions and 50% of the axillary lymph nodes with 99mTc-MDP, and 35% with 99mTc-EPPT, were detected as documented by histology. Our protocol may represent an improvement in the diagnosis and staging of breast cancer.

[Ambulatory phlebectomy. Literature review and personal experience]

Outpatient varicose veins surgery, "Phlébectomie Ambulatoire" (FA) introduced by R. Muller in 1966, is now a widespread technique; modified by many authors with personal tips, FA enables most lower limb varicosities to be treated on an outpatient basis and under local anaesthesia. To achieve good functional results, an accurate preoperative diagnostic examination is mandatory; the authors present a review of the indications of FA and their personal experience. Precision in performing micro-incisions, accurate dissection of the varicosities in the subcutaneous tissue and an adequate postoperative elastic bandage guarantee good aesthetic results. At present the treatment of Saphena magna with FA is debated, but some authors have already reported encouraging results.

Role of glucose-6-phosphate dehydrogenase inhibition in the antiproliferative effects of dehydroepiandrosterone on human breast cancer cells

Epidemiological and experimental studies suggest that dehydroepiandrosterone (DHEA) exerts a protective effect against breast cancer. It has been proposed that the non-competitive inhibition of glucose-6-phosphate dehydrogenase (G6PD) contributes to DHEA antitumor action. We evaluated the effects of DHEA on G6PD activity and on the in vitro proliferation of two human breast cancer cell lines, MCF-7 (steroid receptor positive) and MDA-MB-231 (steroid receptor negative), in a serum-free assay. DHEA inhibition of G6PD was only found to occur at concentrations above 10 microM; at these high concentrations, the growth curve was parallel to the enzyme inhibition curve in both cell lines. In contrast, at concentrations in the in vivo breast tissue concentration range, neither cell growth nor enzyme activity was inhibited. The results failed to confirm DHEA's putative anti-tumor action on breast cancer through G6PD inhibition, as the enzyme blockade only becomes apparent at pharmacological concentrations of the steroid.

[Outpatient evaluation of venous diseases. Role of instrumental diagnostic methods]

Venous investigations have increasingly gained a large part in daily phlebological activity; with the currently available diagnostic tools it's now possible to achieve a "hemodynamic" evaluation in every single patient. This in mandatory for outpatients varicose veins surgery, where sites of reflux must be exactly mapped to avoid unnecessary dissections. The authors present a personal diagnostic protocol (algorithm), they carefully prepared to assess a large number of patients avoiding useless and time-consuming examinations. Results of 100 consecutive examinations are reported; only 15 highly-selected patients required the use imaging techniques studies (echoDoppler, venography). The authors believe that a standardized diagnostic protocol can effectively reduce the number of expensive examinations required and the patients waiting time.

Inhibitory effect of hydroxyflutamide plus tamoxifen on oestradiol-induced growth of MCF-7 breast cancer cells

The antiandrogen flutamide has been reported to exert antiproliferative actions on breast cancer both in vitro and in vivo. Here we study the action of its active metabolite hydroxyflutamide on the oestradiol-induced growth of MCF-7 breast cancer cells. The results show that the antiandrogen inhibits the cell growth. Moreover hydroxyflutamide adds its antiproliferative effect to the action of the antioestrogen tamoxifen. The inhibitory effect is dose-dependent and it is unaffected by tamoxifen concentrations up to levels able to block oestrogen receptors completely. Dihydrotestosterone experiments parallel those on hydroxyflutamide. When the two substances are administered together, neither antagonistic nor additive effects are appreciable. Data are consistent with an androgen-like action of hydroxyflutamide on breast cancer cells. The antiproliferative effect of hydroxyflutamide, without virilizing side-effects, suggests that it is worth exploring its possible employment together with antioestrogens in the treatment of breast cancer patients.

Dihydrotestosterone affects the growth of hormone-unresponsive breast cancer cells: an indirect action

Cell to cell interaction, which plays a crucial role in breast cancer growth, may be regulated by steroid hormones. This study examined dihydrotestosterone (DHT) effects on the interaction between the steroid receptor positive MCF-7 and the steroid receptor negative MDA-MB-231 breast cancer cell lines. The growth of MDA-MB-231 cells was inhibited by medium conditioned by MCF-7 cells grown in presence of DHT but not by medium conditioned by MCF-7 cells grown in presence of both DHT and the antiandrogen hydroxyflutamide. Trypsin pretreatment of conditioned medium abolished its growth-inhibitory effect on hormone-unresponsive cells. DHT itself did not affect the growth of MDA-MB-231 cells when directly added to their culture medium. Data suggest that DHT stimulates, via the androgen receptor, the androgen-responsive breast cancer cells to produce a peptide factor(s) capable of inhibiting the growth of hormone-unresponsive cells.

5-En-androstene-3 beta,17 beta-diol inhibits the growth of MCF-7 breast cancer cells when oestrogen receptors are blocked by oestradiol

Adrenal androgens show a dual and apparently opposite effect on the growth of oestrogen-responsive breast cancer: they stimulate growth on their own, but counteract the growth-stimulatory effect of oestrogens. Focusing on the inhibitory action we have studied the effects of 5-en-androstene-3 beta,17 beta-diol (ADIOL) on the growth of oestrogen-responsive MCF-7 breast cancer cells in the presence of oestrogens (oestradiol and diethylstilboestrol), antiestrogens (tamoxifen) and antiandrogens (hydroxyflutamide). The inhibition of oestrogen-stimulated growth, attained with nanomolar concentrations of ADIOL, was not modified by increasing concentrations of diethylstilboestrol up to 100 nM. This inhibition was counteracted by antiandrogens, which were unable to block the ADIOL stimulatory effect in steroid-free medium. On the other hand, in the presence of tamoxifen ADIOL showed an additive antiproliferative activity also in steroid-free medium, rather than the usual stimulatory effect. These results suggest that ADIOL stimulates breast cancer cell growth via oestrogen receptors, but inhibits oestrogen-stimulated growth via androgen receptors.

Dehydroepiandrosterone antiestrogenic action through androgen receptor in MCF-7 human breast cancer cell line

The possible mechanisms of the inhibitory effect of Dehydroepiandrosterone (DHEA) on the estrogen-induced growth of MCF-7 human breast cancer cells were explored. The impairment of metabolic pathways, via the inhibition of glucose-6-phosphate dehydrogenase (G6PD) activity, was excluded: G6PD activity in MCF-7 homogenate was reduced by DHEA only at a very high concentration (50 microM), while no inhibitory action on the enzyme activity was detected when DHEA was added at the antimitotic concentrations (0.02-0.5 microM). A steroid receptor mediated effect was explored: DHEA might either activate androgen receptors (AR) or partially displace E2 from estrogen receptor (ER). The pure antiandrogens Flutamide and Hydroxyflutamide reversed the inhibitory effect of DHEA on MCF-7 cell growth, whereas both the nonsteroidal estrogen Diethylstilbestrol and the antiestrogen Tamoxifen were ineffective. Results demonstrate that the AR activation plays a pivotal role in the inhibitory action of DHEA on the E2-induced MCF-7 growth.