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Biomedical subjects

S Bianchi

Publications and source records attributed to S Bianchi.

At least 73 records · Page 4Linked to original sources
PubMed2000

Relationships between hepatic melanogenesis and respiratory conditions in the newt, Triturus carnifex.

The Kupffer cells (melanomacrophages) in the livers of lower vertebrates contain varying quantities of melanin according to the season. Specimens of Triturus carnifex raised for 2 months at 6 degrees C and then transferred to water at 22 degrees C show a rapid increase in the hepatic accumulation of the pigment. The Kupffer cells make up more than one fourth of the liver mass in chlorbutol-anesthetized animals isolated for 6-7 hr in hypoxic water at 18 degrees C (to bring the oxygen content in a 620-mL respiratory chamber from 1.1 ppm to 0.0). Thus, hepatic melanin is synthesized when the newt's oxygen supply is inadequate to meet its metabolic needs; melanogenesis, however, requires the presence of oxygen and does not occur in anesthetized specimens immersed in a totally anoxic fluid such as paraffin oil. The intraperitoneal injection prior to hypoxic treatment of 1 mg/g of body weight of kojic acid (inhibitor of the enzyme tyrosinase which catalyzes melanin synthesis) blocks melanogenesis and doubles oxygen consumption. The combination of hypoxia and tyrosinase inhibition causes permanent damage to essential functions of the nervous system, while hypoxic treatment alone has no irreversible consequences. The genic expression of tyrosinase in hypoxia appears to be a physiological response aimed at prolonging survival time in anaerobiosis by lowering the metabolic level; melanin would be an inert subproduct of this function.

Animals↗
PubMed2000

Tumor microvessel density and prognosis in node-negative breast cancer.

Microvessel density (MVD) of breast cancer is widely regarded as a prognostic factor, but results from studies on the most important case series have produced conflicting results. The present study was performed with confirmatory intent to define the prognostic relevance of MVD on a series of 378 node-negative-breast-cancer patients, much larger than any other series previously analyzed. Microvessels were stained using Factor-VIII antibody and an immunoperoxidase reaction. MVD was determined independently by 2 observers according to Weidner's methods. In parallel, cell proliferation was evaluated as S-phase fraction and determined according to the 3H-thymidine-labeling index method (TLI). Estrogen and progesterone receptors were quantitatively assessed using the dextran-charcoal technique. Tumor MVD varied greatly from tumor to tumor (2 to 232 MV/mm2) and was unrelated to patient age and menopausal status, or to tumor size, histology and steroid-receptor status. A significant (p = 0.004) but weak inverse correlation (rs = -0.188) was observed with cell proliferation. Univariate analysis using 40 MV/mm2 as cut-off showed an inverse relation with 5-year relapse-free survival (82% vs. 71%, p = 0.018). This finding was limited to very small tumors, slowly proliferating tumors and ER-negative tumors. Multivariate analysis identified tumor size and TLI, but not MVD, menopausal status or ER as independent prognostic factors.

Breast Neoplasms↗
PubMed2000

Sonographic evaluation of digital annular pulley tears.

OBJECTIVE: To evaluate the sonographic (US) appearance of digital annular pulley (DAP) tears in high-level rock climbers. DESIGN AND PATIENTS: We performed a retrospective analysis of the US examinations of 16 high-level rock climbers with clinical signs of DAP lesions. MRI and surgical evaluation were performed in five and three patients respectively. The normal US and MRI appearances of DAP were evaluated in 40 and three normal fingers respectively. RESULTS: Nine of 16 patients presented a DAP tear. In eight subjects (seven with complete tears involving the fourth finger and one the fifth finger), US diagnosis was based on the indirect sign of volar bowstringing of the flexor tendons. Injured pulleys were not appreciated by US. Tears concerned the A2 and A3 in six patients and the A3 and A4 in two patients. A2 pulley thickening and hypoechogenicity compatible with a partial tear was demonstrated in one patient. MRI and surgical data correlated well with the US findings. Four patients had tenosynovitis of the flexor tendons but no evidence of pulley disruption. US examinations of three patients were normal. In the healthy subjects US demonstrated DAP in 16 of 40 digits. CONCLUSION: US can diagnose DAP tears and correlates with the MRI and surgical data. Because of its low cost and non-invasiveness we suggest US as the first imaging modality in the evaluation of injuries of the digital pulley.

Adult↗
PubMed2000

Multimodality imaging assessment of meniscal ossicle.

A case of meniscal ossicles occurring in the left knee of a 23-year-old woman is presented. Radiographs showed two calcified lesions at the posteromedial aspect of the knee which were interpreted as loose bodies. Sonography, computed tomography arthrography and magnetic resonance imaging showed the fragments within the posterior horn of the medial meniscus permitting a diagnosis of meniscal ossicles. These techniques can detect meniscal ossicles and exclude intra-articular loose bodies.

Adult↗
PubMed2000

US and MR imaging of peripheral nerves in leprosy.

OBJECTIVE: To analyze peripheral nerves with ultrasonography (US) and magnetic resonance imaging (MR) in leprosy and assess the role of imaging in leprosy patients. DESIGN AND PATIENTS: Fifty-eight nerves with abnormal clinical features or electromyograms were examined in 23 leprosy patients by means of gray-scale US, Doppler US and MR imaging. Image analysis included: measurement of nerve cross-sectional area; assessment of nerve structure and MR signal intensities; identification of nerve compression within osteofibrous tunnels; detection of endoneural color flow signals and Gd-DTPA enhancement. Correlations were made with clinical findings and a control group of 20 subjects. Fourteen nerves in active reversal reaction were followed up after therapy. RESULTS: Leprosy nerves were classified into three groups based on imaging appearance: group I consisted of 17 normal-appearing nerves; group II, of 30 enlarged nerves with fascicular abnormalities; group III, of 11 nerves with absent fascicular structure. Group II nerves were from patients subjected to reversal reactions; 75% of patients with group III nerves had a history of erythema nodosum leprosum. Nerve compression in osteofibrous tunnels was identified in 33% of group II and 18% of group III nerves. Doppler US and MR imaging were 74% and 92% sensitive in identifying active reactions, based on detection of endoneural color flow signals, long T2 and Gd enhancement. In 64% of cases, follow-up studies showed decreased color flow and Gd uptake after steroids and decompressive surgery. CONCLUSIONS: US and MR imaging are able to detect nerves abnormalities in leprosy. Active reversal reactions are indicated by endoneural color flow signals as well as by an increased T2 signal and Gd enhancement. These signs would suggest rapid progression of nerve damage and a poor prognosis unless antireactional treatment is started.

Adolescent↗
PubMed2000

Laparoscopic creation of a neovagina in patients with Rokitansky syndrome: analysis of 52 cases.

OBJECTIVE: To evaluate the surgical feasibility and the long-term anatomic and functional results of a new procedure that uses the endoscopic approach to treat uterovaginal agenesis, known as Rokintansky syndrome. DESIGN: Evaluation of surgical feasibility and recording of clinical data over a 12-month follow-up. SETTING: Tertiary referral center for the treatment of female genital malformations. PATIENT(S): Fifty-two patients with vaginal agenesis. INTERVENTION(S): The laparoscopic version of the Vecchietti method was used to create a neovagina. MAIN OUTCOME MEASURE(S): Anatomic success was defined as a neovagina >/=6 cm long, allowing easy introduction of two fingers, within 6 months after corrective surgery. Functional success was considered achieved if the patient reported satisfactory sexual intercourse starting from 6 months after surgery. RESULT(S): The surgical procedure was performed with no major complications and with 100% anatomic success; functional success was obtained in 98.1% of the study population. CONCLUSION(S): In patients with Rokitansky syndrome, the laparoscopic approach for creating a neovagina by the Vecchietti method is simple, safe, and effective.

Adolescent↗
PubMed2000

A randomized study of the effects of tibolone and transdermal estrogen replacement therapy in postmenopausal women with uterine myomas.

OBJECTIVE: To evaluate the effects of two types of hormone replacement therapy, an estrogen-progestin combination and tibolone, on uterine myomas in menopausal women. STUDY DESIGN: Thirty-eight menopausal women with one or more uterine myomas were randomized to treatment with a transdermal system continuously releasing estradiol 50 microg/day combined with oral medroxyprogesterone acetate (MPA) 10 mg/day for 12 days/month or tibolone tablets 2.5 mg/day. The scheduled duration of both treatments was 12 months. Physical examination and abdominal/transvaginal ultrasonography were performed before entering the study and at 3, 6 and 12 months of treatment. At each ultrasonography the overall uterine volume was determined as well as the size of each myoma and the endometrial thickness and characteristics. RESULTS: No statistically significant difference was detected between the two groups at any time during treatment. However, within-group analysis showed a significant increase of uterine volume and of myoma number and size in the estrogen-progestin group, whereas no such increase occurred in the patients treated with tibolone. Also, the mean endometrium width increased significantly from baseline to the end of treatment in the estrogen-progestin group, but not in the tibolone group. CONCLUSIONS: Tibolone seems a valid alternative in menopausal patients with uterine myomas as it provides adequate relief from menopausal symptoms and avoids volume increase of the uterus and myomas.

Administration, Cutaneous↗
PubMed2000

5-Hydroxytryptophan, but not L-tryptophan, alters sleep and brain temperature in rats.

The precise role of serotonin (5-hydroxytryptamine) in the regulation of sleep is not fully understood. To further clarify this role for 5-hydroxytryptamine, the 5-hydroxytryptamine precursors L-tryptophan (40 and 80 mg/kg) and L-5-hydroxytryptophan (25-, 50-, 75-, 100 mg/kg) were injected intraperitoneally into freely behaving rats 15 min prior to dark onset, and subsequent effects on sleep-wake activity and cortical brain temperature were determined. L-5-hydroxytryptophan, but not L-tryptophan, induced dose-dependent changes in sleep-wake activity. During the 12-h dark period, non-rapid eye movement sleep was inhibited in post-injection hours 1-2 by the two lowest L-5-hydroxytryptophan doses tested, while the two highest doses induced a delayed increase in non-rapid eye movement sleep in post-injection hours 3-12. These highest doses inhibited non-rapid eye movement sleep during the subsequent 12-h light period. The finding that L-5-hydroxytryptophan, but not L-tryptophan, induced a dose-dependent and long-lasting decrease in cortical brain temperature regardless of whether or not non-rapid eye movement sleep was suppressed or enhanced contributes to a growing list of conditions showing that sleep-wake activity and thermoregulation, although normally tightly coupled, may be dissociated. The initial non-rapid eye movement sleep inhibition observed following low doses of L-5-hydroxytryptophan may be attributable to increased serotonergic activity since 5-hydroxytryptamine may promote wakefulness per se, whereas the delayed non-rapid eye movement sleep enhancement after higher doses may be due to the induction by 5-hydroxytryptamine of sleep-inducing factor(s), as previously hypothesized. The period of non-rapid eye movement sleep inhibition beginning 12 h after administration of L-5-hydroxytryptophan doses that increase non-rapid eye movement sleep is characteristic of physiological manipulations in which non-rapid eye movement sleep is enhanced. The results of the present study suggest that the complex effects of 5-HT on sleep depend on the degree and time course of activation of the serotonergic system such that 5-HT may directly inhibit sleep, yet induce a cascade of physiological processes that enhance subsequent sleep.

Animals↗
PubMed2000

Ultrasonography of peripheral nerves.

With recent improvements in ultrasound (US) imaging equipment and refinements in scanning technique, an increasing number of peripheral nerves and related pathologic conditions can be identified. US imaging can support clinical and electrophysiologic testing for detection of nerve abnormalities caused by trauma, tumors, and a variety of nonneoplastic conditions, including entrapment neuropathies. This article addresses the normal US appearance of peripheral nerves and discusses the potential role of US nerve imaging in specific clinical settings. A series of US images of diverse pathologic processes involving peripheral nerves is presented.

Carpal Tunnel Syndrome↗
PubMed2000

Causes of inconsistency in diagnosing and classifying intraductal proliferations of the breast. European Commission Working Group on Breast Screening Pathology.

It is now widely recognised that classifying ductal carcinoma in situ (DCIS) of the breast and diagnosing atypical ductal hyperplasia are associated with significant interobserver variation. Two possible reasons for this inconsistency are differences in the interpretation of specified histological features and field selection where morphology is heterogeneous. In order to investigate the relative contribution of these two factors to inconsistent interpretation of intraductal proliferations, histological sections of 32 lesions were sent to 23 European pathologists followed 3 years later by images of small parts of these sections. Kappa statistics for diagnosing hyperplasia of usual type, atypical ductal hyperplasia and ductal carcinoma in situ were 0.54, 0.35 and 0.78 for sections and 0.47, 0.29 and 0.78 for images, respectively, showing that most of the inconsistency is due to differences in morphological interpretation. Improvements can thus be expected only if diagnostic criteria or methodology are changed. In contrast, kappa for classifying DCIS by growth pattern was very low at 0.23 for sections and better at 0.47 for images, reflecting the widely recognised variation in the growth pattern of DCIS. Higher kappa statistics were obtained when any mention of an individual growth pattern was included in that category, thus allowing multiple categories per case; but kappa was still higher for images than sections. Classifying DCIS by nuclear grade gave kappa values of 0.36 for sections and 0.49 for images, indicating that intralesional heterogeneity has hitherto been underestimated as a cause of inconsistency in classifying DCIS by this method. More rigorous assessment of the proportions of the different nuclear grades present could lead to an improvement in consistency.

Breast↗
PubMed2000

Biochemical and functional characterization of the Tn-specific lectin from Salvia sclarea seeds.

SSL, the lectin isolated from Salvia sclarea seeds, recognizes the Tn antigen (GalNAcalpha-O-Ser/Thr), a specific marker of many human carcinomas. Two-dimensional electrophoresis, amino-acid and amino-sugar analysis, and MALDI-TOF MS showed that SSL is an acidic (pI 5.5), 60-61-kDa dimeric glycoprotein composed of apparently identical subunits linked by a single disulfide bond. The apparent molecular mass of SSL in solution determined by equilibrium sedimentation analytical ultracentrifugation was 59 +/- 9 kDa. This value did not change in the pH range 2.5-8.5, indicating that SSL does not associate into higher order structures. Tandem mass spectrometry and methylation analysis of N-glycans released from SSL by hydrazinolysis indicated that SSL possesses 2-3 glycosylation sites occupied with the typical plant glycans Manalpha1-6[(Manalpha1-3)(Xylbeta1-2)]Manbeta1-4 -GlcNAcbeta1-4(Fucalp ha1-3)GlcNAc and [(Manalpha1-3/6)(Xylbeta1-2)]Manbeta1-4-GlcNAcbeta1 -4(Fucalpha1-3)Glc NAc. The influence of adjacent Tn structures on the binding of two Tn-specific lectins (SSL and the isolectin B4 from Vicia villosa) and an anti-Tn monoclonal antibody (mAb 83D4) was evaluated using synthetic Tn glycopeptides. The binding of both lectins to the synthetic Tn glycopeptides was independent of the density of Tn structures. On the other hand, mAb 83D4 only reacted with glycopeptides displaying two or three consecutive Tn structures.

Antibodies, Monoclonal↗
PubMed2000

Gonadotropin-releasing hormone agonist treatment for endometriosis of the rectovaginal septum.

OBJECTIVE: This study was undertaken to evaluate the effectiveness of a 6-month course of gonadotropin-releasing hormone agonist treatment for patients with symptomatic endometriosis of the rectovaginal septum. STUDY DESIGN: Fifteen patients with rectovaginal endometriosis and moderate to severe pain symptoms were the subjects of the study. None of these patients had either clinical or objective evidence of ovarian endometriosis, nor was there evidence of any obstructive lesions of the intestine or ureters. All patients were given leuprolide acetate depot at 3.75 mg, 1 ampule intramuscularly every 28 days, and treatment had a planned duration of 6 months. Follow-up evaluations were set every 2 months during the treatment phase and every 3 months thereafter until the completion of 1 year after discontinuation of medical therapy. At each follow-up visit pain symptoms were recorded, and clinical exploration, transvaginal ultrasonography, and transrectal ultrasonography were performed. RESULTS: Two patients stopped the treatment early after the second and fourth leuprolide doses; in both cases the reason was persistence of pain, and both requested a surgical solution. The other 13 patients showed a marked improvement with respect to pain during the 6-month treatment course but had early pain recurrence after drug suspension; 11 of them required further treatment within the first year of follow-up. The failure rate of gonadotropin-releasing hormone agonist therapy to produce 1-year pain relief after treatment discontinuation was 87% (13/15) on an intent-to-treat basis. The endometriotic lesions showed a slight but significant reduction in size during therapy but had returned to the original volume within 6 months after cessation of the gonadotropin-releasing hormone analog treatment. CONCLUSION: Our results suggest that gonadotropin-releasing hormone analogs should not be considered a real therapeutic alternative to surgical treatment for patients with symptomatic endometriosis of the rectovaginal septum, except possibly in a limited and unpredictable number of cases.

Adult↗
PubMed2000

Laparoscopic creation of a neovagina in a woman with a kidney transplant: case report.

The successful use of Vecchietti's technique for creating a neovagina in a case of Rokitansky syndrome with an associated transplanted kidney is reported. The technique is performed by means of a laparoscopic approach, adapted to the special anatomical situation, in order to avoid renal injuries. The accomplishment of a normally functioning neovagina, with no intra-operative or post-operative complications, proves that this technique can also be applied satisfactorily to this type of patient.

Adult↗
PubMed2000

US of nerve entrapments in osteofibrous tunnels of the upper and lower limbs.

The diagnosis of nerve entrapment at osteofibrous tunnels relies primarily on clinical and electrodiagnostic findings. Recently, the refinement of high-frequency broadband transducers with a range of 5-15 MHz, sophisticated focusing in the near field, and sensitive color and power Doppler technology have improved the ability to evaluate peripheral nerve entrapment in osteofibrous tunnels with ultrasonography (US). In the upper limb, osteofibrous tunnels amenable to US examination include the carpal tunnel for the median nerve and the cubital and Guyon tunnels for the ulnar nerve. In the lower limb, these tunnels include the fibular neck for the common peroneal nerve, the tarsal tunnel for the posterior tibial nerve, and the intermetatarsal spaces for the interdigital nerves. High-resolution US allows direct imaging of the involved nerves, as well as documentation of changes in nerve shape and echotexture that occur in compressive syndromes. A spectrum of extrinsic causes of entrapment, such as tenosynovitis, ganglia, soft-tissue tumors, bone and joint abnormalities, and anomalous muscles, can also be diagnosed with US. With continued experience, it is likely that this technique will be increasingly used to evaluate nerve entrapment syndromes.

Arm↗
PubMed2000

Surgical treatment of chordee without hypospadias.

OBJECTIVE: The aim of this study was to retrospectively assess the efficacy of the surgical techniques commonly used in three types of chordee without hypospadias (Devine and Horton classification). METHODS: Twenty-six patients, ranging in age from 3 to 14 years, had chordee without hypospadias and underwent Nesbit dorsal plication (9 cases out of 12, type III), associated extensive mobilization of the urethra (10 cases out of 10, type II), and vascularized neourethra (3 cases out of 4, type I). RESULTS: Eleven subjects undergoing follow-up investigation for the milder forms of chordee were satisfied with the outcome achieved; there was no impediment of any kind in the sex lives of 5 adult subjects. Of the 11 patients undergoing follow-up after more complex surgery for Devine and Horton type I-II chordee without hypospadias, a residual abnormal curvature was present in 4 subjects. These patients were submitted to one or more reoperations with outcomes defined as satisfactory. CONCLUSION: To avoid the risks of persistent chordee, the authors suggest more radical and accurate operations for the treatment of type I and II pseudohypospadias.

Adolescent↗
PubMed2000

Instability at dinucleotide and trinucleotide repeats in breast cancer.

We analyzed 7 mono-, 6 di- and 2 trinucleotide repeat loci in a well characterized series of 69 breast cancer cases, treated in the period 1985-1986 and followed for 12 years. Tumor-associated allele contractions or expansions were observed only at di- and trinucleotide repeats, and were detected in 14/69 cases (20%), of which 7 (10%) showed instability at 2 or more loci (10%). No alterations were detected at mononucleotide repeats known to be unstable in gastrointestinal tumors with the microsatellite mutator phenotype. Disease-free survival at 5 years, overall survival at 12 years of follow-up, tumor stage, estrogen/progesteron receptor status, and expression of the Ki-67 proliferation marker were independent of microsatellite status.

Adult↗
PubMed2000

[Surgical treatment of thyroid microcarcinoma].

Thyroid microcarcinoma is nowaday defined as a tumor of one centimeter or less in the maximum diameter. It occurs in less than five per cent of all thyroid carcinomas. In personal experience four thyroid microcarcinomas have been found in specimens from 121 thyroidectomies and have been retrospectively reviewed clinical data and the long term follow-up of the patients. Total thyroidectomies nor prophylactic lymphadenectomies were never performed. All patients at present are well. Our purpose was to focus on the current surgical treatment of microcarcinoma. Many hypotheses are done to explain pathogenesis and fairly good prognosis of thyroid microcarcinomas, without univocal conclusions. Almost all authors agree that microcarcinoma of the thyroid gland is a low-aggressive tumor, with good biological behaviour, but the therapeutic strategies are not codified yet. Particularly, doubt still exists about the choice between total thyroidectomy and more conservative procedure, and lymphadenectomy, especially when tumor is found in specimens after surgery for benign disease. In conclusion, in our opinion conservative management is the best choice, provided that the patient is included in a correct long-term follow-up.

Adult↗