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Biomedical subjects

S Bianchi

Publications and source records attributed to S Bianchi.

At least 55 records · Page 3Linked to original sources
PubMed2002

Do CLL B cells correspond to naive or memory B-lymphocytes? Evidence for an active Ig switch unrelated to phenotype expression and Ig mutational pattern in B-CLL cells.

Recent work suggests that chronic lymphocytic leukemia (B-CLL) expressing unmutated immunoglobulin V genes could correspond to the proliferation of naive B cells whereas those expressing mutated genes, may correspond to the proliferation of post-germinal center B cells. Current data from gene profiling expression have failed to demonstrate a clear-cut distinction between these two forms of B-CLL disease. In the present study, we have investigated the complete V(H) nucleotide sequence and the presence of RNA transcripts from different C(H) domains in 25 B-CLL patients. Our results demonstrate that: (1) expression of IgD is not related to the mutational frequency and activation of the isotype switch pathway; (2) isotype switch, leading to simultaneous expression at the transcriptional and protein level of IgM, IgD, IgG and IgA, occurs in a small percentage of patients, and (3) different mechanisms such as VDJ duplication and trans-splicing or RNA splicing of long nuclear transcript, could be involved in isotype switch. Our results highlight the difficulty in assigning a normal counterpart to B-CLL cells and raise the possibility that a different B cell development pathway, independent from classical germinal centers, might exist in B-CLL.

Adult↗
PubMed2001

Ultrasound of the elbow.

Ultrasonography (US) is an efficient alternative to magnetic resonance (MR) imaging for evaluation of soft tissues of the elbow. US is able to diagnose several abnormalities affecting tendons, muscles, ligaments and bursae around the elbow joint. In cubital tunnel syndrome, US identifies ulnar nerve abnormalities and extrinsic lesions that may cause nerve entrapment. Occult fractures, osteophytes and intra-articular loose bodies can also be imaged. In para-articular swelling, US is able to assess the presence of capsular and synovial processes and to differentiate them from soft tissue tumors. Key advantages of this technique include cost-effectiveness, availability and ability to perform a dynamic examination.

Elbow Joint↗
PubMed2001

Magnetization transfer and diffusion tensor MR imaging of the optic radiations and calcarine cortex from patients with Leber's hereditary optic neuropathy.

Optic nerve abnormalities are easily detectable in patients with Leber's hereditary optic neuropathy (LHON), using magnetic resonance imaging (MRI). However, the presence of structural changes in the optic radiations and calcarine cortex of these patients is still an unresolved issue. In this study, we obtained magnetization transfer (MT) and diffusion tensor (DT) MRI to investigate the integrity of these structures in patients with LHON. Dual echo, MT- and DT-MRI scans of the brain were obtained from 10 men with LHON and 10 healthy sex- and age-matched controls. After image co-registration, we obtained MT ratio (MTR), average diffusivity (D) and fractional anisotropy (FA) maps. MTR, D and FA values for the white matter of the optic radiations and MTR and D values for the calcarine cortex were obtained using a region of interest (ROI) analysis. No macroscopic abnormalities were detected in any of the scans from LHON patients and controls. No statistically significant differences of MTR, D or FA values were found for any of the regions studied in LHON patients and healthy controls. Our results suggest that, in patients with LHON, the optic radiations and the calcarine cortex are spared from structural damage, both at a macroscopic and a microscopic level.

Adult↗
PubMed2001

Diagnostic imaging of tumors of the hand and wrist.

Tumors of the hand and wrist most commonly result from dystrophic lesions and hamartomas. Neoplastic lesions are rare. Imaging modalities are required for their detection and accurate location, careful assessment of the internal structure and borders, evaluation of the relation with surrounding tendons, nerves, and vessels, and are also required for staging. A variety of imaging techniques, including standard radiographs, sonography, CT, and MRI, can be obtained. The aim of this article is to present paradigmatic images of a variety of expansible lesions of the hand and wrist and to describe and compare the diagnostic findings of different imaging techniques.

Bone Neoplasms↗
PubMed2001

Genetic leukoencephalopathies with unknown metabolic pathogenesis.

The authors describe the principal forms of genetic leucodystrophies with unknown metabolic pathogenesis, indicating their main clinical signs and the new findings concerning the molecular genetic that are useful for the laboratory confirmation of the clinical suspicion.

Demyelinating Diseases↗
PubMed2001

Use of a levonorgestrel-releasing intrauterine device in the treatment of rectovaginal endometriosis.

OBJECTIVE: To evaluate the effectiveness of a levonorgestrel-releasing IUD as therapy for endometriosis of the rectovaginal septum. DESIGN: Prospective therapeutic non-randomized, self-controlled clinical trial analyzing changes in pain symptoms and size of lesions induced by the levonorgestrel-releasing IUD over 12 months. SETTING: Tertiary referral center for treatment of deep endometriosis. PATIENT(S): Eleven symptomatic patients with rectovaginal endometriosis. INTERVENTION(S): A levonorgestrel-releasing IUD was inserted and maintained for 12 months. MAIN OUTCOME MEASURE(S): Severity of dysmenorrhea, pelvic pain, and deep dyspareunia were assessed before insertion of the IUD and throughout treatment. The size of rectovaginal endometriotic lesions were evaluated by using transrectal and transvaginal ultrasonography. RESULT(S): Dysmenorrhea, pelvic pain, and deep dyspareunia greatly improved and the size of the endometriotic lesions was significantly reduced by treatment. CONCLUSION(S): Insertion of a levonorgestrel-releasing IUD alleviates pain and reduces the size of lesions in patients with endometriosis of the rectovaginal septum.

Adult↗
PubMed2001

Ultrasound of the elbow.

This article describes the use of ultrasound (US) in the evaluation of the elbow. US is able to visualize several abnormalities affecting tendons, muscles, ligaments and bursae around the elbow joint as well as to delineate the nature of soft-tissue swelling, such as a space-occupying lesion or synovial enlargement. Occult fractures, osteophytes and intra-articular loose bodies can be depicted with this technique as well. At the cubital tunnel, US allows accurate imaging of the ulnar nerve and to document changes that occur in compressive syndromes. Over other imaging modalities, US offers several key advantages, including cost effectiveness, availability and ability to perform a dynamic examination of tendon movement and joint motion. With continued experience, it is likely that the use of US will increase further with regards to evaluation of soft-tissue abnormalities of the elbow.

Elbow↗
PubMed2001

Ultrasound of the hand.

A recent development of high resolution transducers has increased the possibility to evaluate the most superficial body structures. The assessment of the normal anatomy and of the pathological changes of the hand and the wrist has become popular among musculoskeletal sonologists and nowadays ultrasound is considered one of the first line imaging techniques in the assessment of this district. Ultrasound must always be performed after a standard radiograph since the association of the two techniques can diagnose a wide variety of disorders. Some lesions however cannot be detected and require more invasive and expensive modalities (CT, MRI, CT and MRI arthrography). The goal of this article is to present the ultrasound appearance of inflammatory and traumatic diseases of the hand and wrist as well as the findings in entrapment neuropathies and soft tissue tumors.

Hand↗
PubMed2001

Post-operative GnRH analogue treatment after conservative surgery for symptomatic endometriosis stage III-IV: a randomized controlled trial.

BACKGROUND: In order to decrease endometriosis recurrence after surgical therapy, it has been proposed to use a post-surgical oestrogen-lowering medical treatment. Results from previous trials on this topic are contradictory. METHODS: A total of 89 women were randomized, by computer-generated list, after laparoscopic conservative surgery for symptomatic endometriosis stage III-IV to receive monthly i.m. injections of gonadotrophin-releasing hormone (GnRH) analogue, leuprolide acetate depot (3.75 mg) for 3 months (n = 44) or to an expectant management (n = 45). All patients were followed up every 6 months for evaluation of pain symptoms, fertility and objective disease recurrence. RESULTS: During the follow-up, which ranged from 6-36 months, five (33%) of the 15 women who wanted children and who were allocated the GnRH analogue and six (40%) of the 15 given no treatment became pregnant (not significant). Moderate/severe pelvic pain recurred during the follow-up in 10 (23%) of the women allocated the GnRH analogue and 11 (24%) of those allocated no treatment; the cumulative pain recurrence rates at 18 months were 23 and 29% respectively (not significant). Four women (9%) treated with GnRH analogue and four women (9%) who received no treatment had objective disease recurrence as demonstrated by gynaecological examination and/or pelvic ultrasonography. CONCLUSIONS: This study does not support the routine post-operative use of a 3 month course of GnRH analogue in women with symptomatic endometriosis stage III-IV.

Adult↗
PubMed2001

Magnetic resonance imaging, magnetisation transfer imaging, and diffusion weighted imaging correlates of optic nerve, brain, and cervical cord damage in Leber's hereditary optic neuropathy.

OBJECTIVES: Leber's hereditary optic neuropathy (LHON) is a mitochondrial disease leading to bilateral loss of central vision and severe optic nerve atrophy. A subtype of LHON presents additional clinical and MRI aspects indistinguishable from those of multiple sclerosis (MS) (LHON-MS). In patients with LHON or LHON-MS, an assessment was made of (a) the severity of optic nerve damage, using MRI and magnetisation transfer imaging (MTI), and (b) the presence and extent of macroscopic and microscopic pathology in the brain and cervical cord, using MRI and MT ratio (MTR) and mean diffusivity (D) histogram analysis. METHODS: Ten patients with LHON, four with LHON-MS, and 20 age and sex matched healthy controls were studied. For the optic nerve and the brain, dual-echo turbo spin echo (TSE), T1 weighted spin echo, and MT images were obtained. For the brain, fast fluid attenuated inversion recovery (fast FLAIR) and diffusion weighted images were also obtained. For the cervical cord, fast short tau inversion recovery (STIR) and MT images were obtained. The volume and the average MTR value of both the optic nerves were measured. MTR and histograms of the normal appearing brain tissue (NABT) and MTR histograms of the whole cervical cord tissue were created. RESULTS: The mean values of optic nerve volumes and MTR were significantly lower in patients with LHON than in healthy controls. Mean NABT-MTR histogram peak height was significantly lower in patients with LHON than in controls, whereas no significant difference was found for any of the cervical cord MTR histogram derived measures. Average diffusivity (D) was higher in patients with LHON than in controls. Optic nerve volume and MTR value and mean NABT-MTR were lower in patients with LHON-MS than in those with LHON. CONCLUSIONS: The severity of optic nerve pathology in LHON is measurable in vivo using MRI and MTI. MTR and histogram analysis suggests that microscopic brain damage occurs in LHON and that it is more severe in the MS-like form of the disease.

Adult↗
PubMed2001

Relationship between the morphological evaluation of the pituitary and the growth hormone (GH) response to GH-releasing hormone Plus arginine in children and adults with congenital hypopituitarism.

The relationship between the hypothalamus-pituitary morphology and the somatotroph responsiveness to maximal provocative tests exploring the GH releasable pool is still unclear. We evaluated the GH-releasing effect of GHRH plus arginine (GHRH plus Arg) in 36 patients with congenital GH deficiency (GHD) according to their pituitary magnetic resonance imaging findings, consisting of anterior pituitary hypoplasia, stalk agenesis (neural and or vascular component), and posterior pituitary ectopia. Seventeen children (12 boys and 5 girls, aged 1--5.2 yr) were evaluated at the time of diagnosis of GHD (mean age, 3.6 +/- 1.4 yr), and 19 adults (13 males and 6 females, aged 15.9-28.6 yr) with childhood-onset GHD were reevaluated after completion of GH treatment (at least 6 months of withdrawal) at a mean age of 20.5 +/- 3.5 yr. Eleven children had isolated GHD, and 6 had multiple pituitary hormone deficiency (MPHD) whereas 7 adults had isolated GHD, and 12 had MPHD. A residual vascular component of the pituitary stalk was visualized in 7 children and 7 adults with isolated GHD, whereas magnetic resonance imaging showed complete pituitary stalk agenesis (both vascular and neural components) in 10 children and 10 adults, including 16 with MPHD (6 children) and 4 children with isolated GHD. In the children, the median peak GH response to GHRH plus Arg (7.6 microg/L; range, 2.4--40.2 microg/L) was significantly higher than that in the adults (1.8 microg/L; range, 0.8--37.4 microg/L; P = 0.0039); it was also significantly higher in the isolated GHD patients (18 microg/L; range, 3.3--40.2 microg/L) than in those with MPHD (1.9 microg/L; range, 0.8--7.6 microg/L; P = 0.00004). In the patients with residual vascular component of the pituitary stalk the median peak GH responses to GHRH plus Arg (19.1 microg/L; range, 1.6--40.2 microg/L) was significantly higher than that in patients with complete pituitary stalk agenesis (2.2 microg/L; range, 0.8--8.8 microg/L; P = 0.00005). There was a trend toward a decrease with age in peak GH response to GHRH plus ARG: Mean serum insulin-like growth factor I (IGF-I) levels were 36 +/- 7.1 microg/L in the children and 63.5 +/- 22.6 microg/L in the adults (P = 0.0001). The mean IGF-I level did not differ between the children with (35.7 +/- 4.8 microg/L) and those without (36.3 +/- 8.7 microg/L) the pituitary stalk; it was much higher in the adults with residual vascular pituitary stalk (81.1 +/- 17.7 microg/L) than in those with complete pituitary stalk agenesis (47.7 +/- 12.5 microg/L; P = 0.0002). The IGF-I level was 36.1 +/- 6.7 microg/L in the isolated GHD children and 36 +/- 8.6 microg/L in those with MPHD; levels were 82.1 +/- 19.4 and 52.7 +/- 16.8 microg/L respectively, in the adults (P = 0.003). In this study we have confirmed that the partial integrity of the hypothalamic pituitary connections is essential for GHRH plus Arg to express its GH-releasing activity and have shown that this provocative test is able to stimulate GH secretion to a greater extent in those patients with GHD, but with a residual vascular component of the pituitary stalk. This test is reliable in the diagnosis of congenital hypopituitarism in both children and adults when associated with complete pituitary stalk agenesis and MPHD. In younger children with congenital GHD but less severe impairment of the pituitary stalk the GH response to GHRH plus Arg may be within the normal range; deterioration of pituitary GH reserve with a GH response of less than 10 microg/L after 20 yr of age makes this test very sensitive in the diagnosis of adult GHD.

Adolescent↗
PubMed2001

Age dependence of human gastrocnemius Mg2+: fitting 31P-NMR spectra using quantum mechanics-based prior knowledge.

The age dependence of human gastrocnemius Mg2+ concentration is demonstrated. To quantitate Mg2+ concentration, an original and accurate fitting algorithm using quantum mechanics-based prior knowledge is detailed. In a group of 28 volunteers (14 females) in the age range 5-80 years, pH, PCr/ATP and Pi/ATP values in the gastrocnemius were 7.02 +/- 0.02 pH, 4.16 +/- 0.33 and 0.13 +/- 0.02, respectively and independent of age and sex. By contrast, intracellular Mg2+ concentration (mM) decreased linearly (p < 0.05) with age (Mg2+ = 0.7803 +/- 0.0247-0.0027 +/- 0.0005 * age). No difference was found between sexes. From these results, it follows that care must be taken when comparing muscle Mg2+ data from subjects of different age. The hypothesis can be put forward that during aging insufficient intake and/or increased depletion of Mg2+ (e.g., intestinal hypoabsorption or urinary leakage) may affect the musculoskeletal system.

Adenosine Triphosphate↗
PubMed2001

Human gastrocnemius medialis pennation angle as a function of age: from newborn to the elderly.

The aim of the present study was to quantify changes in human skeletal muscle pennation angle (F theta) values during growth and adult life. The human gastrocnemius medialis muscle of 162 subjects (96 males and 66 females) in the age range 0-70 years was scanned with ultrasonography. The subjects were laying prone, at rest, with the ankle maintained at 90 degrees with all muscles relaxed. F theta increased monotonically starting from birth (0 years) and reached a stable value after the adolescent growth spurt. There was a significant (p < 0.05) linear relationship between F theta and muscle thickness (TK). F theta = 0.84 (+/- 0.09) * TK + 3.15 (+/- 1.13). Human gastrocnemius medialis F theta and TK data found in the literature seem to fit the F theta-TK plot in a coherent manner, independent of the physiological or anatomical characteristics of the subject. The present findings indicate that F theta is not a constant parameter but evolves, as is the case for bone length and height, as a function of age.

Adolescent↗
PubMed2001

[Cryptohypospadias: Surgical approach and long-term results].

BACKGROUND: Chordee without hypospadias is a rare morphological abnormality of the penis capable of interfering with sexual function. Usually, cases of chordee without hypospadias require surgical correction, and the aim of this study is to assess the efficacy of the techniques normally used in this pathology. METHODS: The authors analyze the surgical outcomes achieved in 34 patients presenting various degrees of ventral or lateral curvature of the erect penis and operated on in our department over the past 22 years. Twenty-nine subjects attended for follow-up, including 13 who have now reached adulthood. RESULTS: The milder forms of chordee without hypospadias (Horton and Devine type III and lateral deviations of the penis) all benefited from minor surgery (dermal grafts and Nesbit dorsal plication of the contralateral penile tunica albuginea) and were corrected with a single operation. The most serious forms of chordee without hypospadias where the hypoplasia variously affected the corpus spongiosum, Buck's fascia and the dartos fascia (Horton and Devine types I and II), were submitted to a supplementary extensive urethral mobilization or occasionally a urethroplasty and one-third of them presented persistent residual curvature. CONCLUSIONS: The authors advocate a more aggressive surgical approach (urethroplasty and/or patches on the ventral tunica albuginea as an alternative to urethral mobilisation) in subjects with more pronounced defects.

Adolescent↗
PubMed2001

[Reconstruction of the vas deferens: an experimental study on the rat].

BACKGROUND: A microsurgical technique for reconstruction of the vas deferens on an absorbable transanastomotic stent in the rat is described. METHODS: A microsurgical end-to-end anastomosis of the vas deferens was performed in a group of 10 rats (group A) by suturing with Nylon 10-0 interrupted stitches. In another 10 rats (group B) the same microsurgical anastomosis was performed after insertion of a 0.5 cm long intraluminal chromic catgut 4.0 stent. RESULTS: Sixty days postoperatively all 20 animals were submitted to roentgenography of the vas deferens. The vas deferens proved radiographically undetectable in 8/10 rats in the unstented group A (80%), whereas the entire course of the vas could be traced in 9/10 rats in group B (90%). CONCLUSIONS: The encouraging results obtained with this alternative technique, even on structures of limited diameter, suggests that it may be possible to use this procedure in children.

Animals↗
PubMed2001

[Somatostatin receptors in non-endocrine tumours].

The study of the antiproliferative action of somatostatin (ss) is important not only to understand the regulation of neuroendocrine tumours that express receptors (sst), but also non-endocrine tumours which express these receptors. We previously demonstrated the presence of sst2 in a wide panel of cell lines from human neuroblastoma. Although hypotheses have been put forward that treatment with ss or its analogs may be beneficial in oncological patients, this does not appear to be the case in neuroblastoma; patients with high sst2 levels (who are therefore sensitive to ss treatment) have per se a relatively positive outcome. Therefore, adjuvant treatment with ss is not necessary. Viceversa, patients with a poor prognosis are essentially characterized by a low expression of sst2 (and therefore are insensitive to a therapy with ss). In these patients adjuvant treatment with ss might be indicated, but would have little chance of success. Although the majority of neuroendocrine tumours expresses sst2, pancreas and prostate cancer express sst1 but not sst2, and are therefore insensitive to octreotide treatment which binds preferentially to sst2. Tumours like colorectal carcinoma and breast cancer also express sst2 in their more favourable forms. However, the concentration of sst2 in colorectal cancer is similar, if not lower than that in the surrounding normal tissue. Therefore, the probability of successful adjuvant therapy with ss is relatively low. In breast cancer, it is possible that sensitivity to estrogens may have a positive influence on the expression of sst2. This might justify clinical trials with ss in breast cancer.

Adenocarcinoma↗
PubMed2000

Intranasal immunization with mumps virus DNA vaccine delivered by influenza virosomes elicits mucosal and systemic immunity.

To improve the efficiency of liposome-mediated DNA transfer as a tool for gene therapy or vaccinology, we have further developed a new delivery system based on the modified immunopotentiating reconstituted influenza virus (IRIV). In this study, we engineered a plasmid DNA vector expressing the mumps virus hemagglutinin or the fusion protein. The administration of this DNA vaccine delivered by influenza virosomes, in combination with the mucosal adjuvant Escheriagen via the intranasal route, was efficient for inducing an immune response, both mucosally and systemically, in mice. The production of IgG2a mumps virus-specific antibodies and the secretion of interleukin 10 (IL-10) by antigen-specific T cells indicated that not only Th1 but also Th2 responses were induced by this DNA vaccine formulation. These results suggest that cationic virosomes in combination with Escheriagen may have great potential as an efficient delivery system for intranasal DNA immunization and provide an immune barrier at the mucosal sites.

Administration, Intranasal↗