The prevention and treatment of amputation neuromata by silicone capping

A technique of silicone capping of amputated sciatic or tibial nerves was evaluated in a single litter of ten New Zealand white rabbits (eight experimental, two control). All nerves and caps were evaluated 12 and 4 weeks after operation. Neuroma formation was prevented when a lengh:diameter ratio of 5:1 (minimum) to 10:1 (maximum) of the cap was observed and a smooth, filmy, nonreactive capsule around all nerve ends and caps was noted. Eighteen patients with 38 traumatic neuromata in the upper extremity were treated by silicone capping and were evaluated an average of 41 months after operation. Of these 18 patients, 17 underwent revision surgery for the specific purpose of relieving disabling neuroma pain. Two patients developed a causalgic state. One patient had recurrence of symptoms in one of four nerves capped and was relieved by reoperation and recapping. The remaining 15 patients were relieved of their preoperative complaints.     

Assessment of skeletal muscle ventricle function using tissue velocity imaging

Because the visibility of homeless persons congregating in urban areas has increased since the 1980's, the relationship between homelessness and mental illness has caused more and more concern. A multitude of epidemiological surveys have been organized in Great Britain, Australia, Canada, and mainly in United States, and have attempted to evaluate scientifically the psychiatric morbidity of this population. This literature review reveals disparity of epidemiological methods in assessing the type and extent of mental illness among homeless adults. The lack of consensual definition of homelessness, the choice of different settings in which the research is organized (street, health centres, shelters), and the use of diverse instruments of psychiatric evaluation (diagnosis by clinician, by scale or by structured diagnostic interview) lead to a great disparity of the results. Thus, 1/3 of the homeless adults had prior history of psychiatric hospitalisation. Rates of psychosis range to 70% and it is estimated that 4% to 74% of the homeless persons suffer from affective disorders. Substance abuse disorder remains a problem for a significant number of these individuals, with a high frequency of dual diagnosis. Such divergent data highlight the anglo-saxon debate between those who accuse desinstitutionnalisation as a reason of homelessness, and those who blame the socioeconomic background.     

Pre-B cell receptor-mediated selection of pre-B cells synthesizing functional mu heavy chains

Ig gene rearrangements could generate V(H)-D-J(H) joining sequences that interfere with the correct folding of a mu-chain, and thus, its capability to pair with IgL chains. Surrogate light (SL) chain might be the ideal molecule to test the capacity of a mu-chain to pair with a L chain early in development, in that only pre-B cells that assemble a membrane mu-SL complex would be permitted to expand and further differentiate. We have previously identified two SL chain nonpairing V(H)81X-mu-chains with distinct V(H)-D-J(H) joining regions. Here, we show that one of these V(H)81X-mu-chains does not rescue B cell development in J(H) knock-out mice, because flow cytometric analysis of bone marrow cells from V(H)81X-mu transgenic J(H) knock-out mice revealed normal numbers of pro-B cells, but essentially no pre-B and surface IgM+ B cells. Immunoprecipitation analysis of transfected pre-B and hybridoma lines revealed that the same mu-chain fails to pair not only with SL chain but also with four distinct kappa L chains. These findings demonstrate that early pre-B cells are selected for maturation on the basis of the structure of a mu-chain, in particular its V(H)-D-J(H) joining or CDR3 sequence, and that one mechanism for this selection is the capacity of a mu-chain to assemble with SL chain. Therefore, we propose a new function of SL chain in early B cell development: SL chain is part of a quality control mechanism that tests a mu-chain for its ability to pair with conventional L chains.     

Treatment of mucosa-associated lymphoid tissue lymphoma of the stomach with radiation alone

PURPOSE: Mucosa-associated lymphoid tissue (MALT) lymphoma of the stomach (MLS) has recently been defined as a distinct clinicopathologic entity, often associated with Helicobacter pylori infection. Many regard antibiotic therapy as the primary treatment of MLS, but in the absence of H pylori infection, or when salvage of antibiotic failures is required, gastrectomy and/or chemotherapy have frequently been used. This study evaluates the efficacy of low-dose radiotherapy alone as an alternative to surgery. PATIENTS AND METHODS: Seventeen patients with stage I to II(2) low-grade MLS without evidence of H pylori infection or with persistent lymphoma after antibiotic therapy of associated H pylori infection were included in this series. Median age was 69 years (range, 39 to 84). Median total radiation dose was 30 Gy (range, 28.5 to 43.5 Gy) delivered in 1.5-Gy fractions within 4 weeks to the stomach and adjacent lymph nodes. Following treatment, all patients underwent endoscopic evaluation and biopsy at a median of 4 months, at 6-month intervals to 2 years, and annually thereafter. RESULTS: All obtained a biopsy-confirmed complete response. At a median follow-up time of 27 months (range, 11 to 68) from completion of radiotherapy, event-free survival was 100%. Treatment was well tolerated, with no significant acute side effects. All remained asymptomatic at last follow-up. CONCLUSION: These results suggest that effective treatment of MLS with low-dose radiation therapy alone is feasible and safe, and allows stomach preservation. Longer follow-up evaluation is required to determine the long-term efficacy of this treatment approach and its side effects. Further studies should clarify the indications for radiotherapy in H pylori-negative or antibiotic-resistant cases of MLS.     

Interleukin-1 beta stimulates adrenocorticotropin and corticosterone release in 10-day-old rat pups

Clinical, radiological and biological features of 19 cases of serologically proven Mycoplasma pneumoniae pneumonia were compared with those of 21 cases of other types of pneumonia. Some clinical features were more frequent in M pneumoniae: patients older than 5 years, association with upper respiratory tract infection, skin rashes, acute course, unsuccessful treatment with penicillin. There were no specific radiological features. When compared with the complement fixation method, the serological diagnosis using agglutination technique appears to be more sensitive.     

Molecular modeling studies on ligand binding to sialidase from influenza virus and the mechanism of catalysis

A molecular modeling study has been used to investigate the structural and energetic aspects of substrate and inhibitor binding and the mechanism of catalysis of influenza virus sialidase. A detailed analysis of the interactions of both N-acetylneuraminic acid (Neu5Ac,1) and a number of transition-state analogues with the active site of influenza A sialidase at an atomic level is reported. In each case the calculated structures favorably agreed with the results from X-ray studies. A qualitative agreement between the calculated binding energies for inhibitors with positive substituents at the C4 position on the sugar ring and experimental Ki values was observed. We propose that the hydrolysis of sialosides occurs via an SN1 type mechanism that is facilitated through an activated solvent water molecule which can be expelled upon inhibitor binding. A reaction scheme is presented that is consistent with previously observed crystallographic structures, anomeric products, and isotope effects.