Spontaneous regression of a lumbar disc herniation: case report.

BACKGROUND: The phenomenon of the spontaneous disappearance of herniated discs is well known. CASE REPORT: The case of a 74-year-old male presenting with a large disc herniation at L5-S1, experiencing moderate sciatic pain, and having the straight-leg-raising test positive at 30 degrees is presented. The disc herniation was documented by computed tomography. He was treated conservatively with medication and physical therapy. One year later the patient was clinically reevaluated. He proved to be symptom-free and the follow-up computed tomography revealed spontaneous disappearance of the herniated disc fragment. The disc regression could have been due to dehydration, resorption as a result of an inflammatory reaction, or retraction into the intervertebral space. CONCLUSIONS: This report discusses the three aforementioned possible explanations and underlines the need for limiting surgical treatment strictly to patients with neurological deficits, severe unremitting leg pain despite conservative measures, and repeated time loss from work.     

Herpes Simplex Virus Type 1 (HSV-1) Strain HSZP Host Shutoff Gene: Nucleotide Sequence and Comparison with HSV-1 Strains Differing in Early Shutoff of Host Protein Synthesis

The UL41 gene of the HSZP strain of herpes simplex virus type 1 (HSV-1) defective with respect to the early shutoff of host protein synthesis was sequenced and compared with the corresponding HSV-1 strain KOS and 17 gene sequences. In comparison with strain 17, nine mutations (base changes) were HSZP specific, five KOS specific and four were common for both strains. Nine mutations caused codon changes. Three of these mapped to the nonconserved regions and the others to the conserved regions of the functional map of UL4l gene. One KOS specific mutation mapped to the region responsible for the binding of the virion host shutoff (vhs) protein to the alpha-transinducing factor (VP16). The possible relationship between mutations and host shutoff function is discussed. The nucleotide sequence data of the UL41 gene of HSZP and KOS have been submitted to the Genbank nucleotide database and have been assigned the accesion numbers Z72337 and Z72338. This revised version was published online in July 2006 with corrections to the Cover Date.     

Specificity of gamma delta receptor bearing T cells.

T cells expressing the gamma delta receptor heterodimer can recognize a broad array of different antigens, including classical and non-classical major histocompatibility complex (MHC) proteins, MHC-like CD1 antigens, and bacterial antigens such as the mycobacterial heat shock proteins and staphylococcal enterotoxins. Reactivity to self antigens including autologous stress proteins implicates TCR gamma delta T cells in autoimmune disease. It is as yet unclear whether the responses of gamma delta T cells specific for soluble proteins are restricted by conventional or non-classical MHC molecules. Correlations of TCR gamma delta usage with specificity suggest that, like TCR alpha beta, sequences encoded within both the V regions and the V(D)J junctions are important in determining receptor specificity.     

Prospective adverse event risk evaluation in clinical trials

Health Care Management Science - Proactive and objective regulatory risk management of ongoing clinical trials is limited, especially when it involves the safety of the trial. We seek to...     

The flow of forage particles and solutes through segments of the digestive tracts of cattle

An experiment was conducted to investigate the compartmental mean residence time, (CMRT) of feed residues in segments of gastrointestinal digesta of mature Holstein steers. The objective was to evaluate assumptions that feed residues flow through ruminal digesta as sequential mixing pools having age-dependent (GN) and age-independent (G1) distributed residence times respectively (GN-->G1 flow). The basal diet was a semi-tropical hay containing 98 g crude protein and 503 g apparently digestible DM per kg DM. The hay was consumed and feed residues of different size and/or previous digestion from the hay were inserted into the reticulo-rumen (rumen) and abomasum. Marker profiles appearing at the duodenum and faeces were fitted to various compartment models to estimate CMRT. Post-abomasal CMRT did not differ among solutes or feed residues of different size and previous digestion and constituted only 5.8% of the CMRT for the entire gastrointestinal tract. Markers initially applied to orally or ruminally dosed feed residues exhibited profiles in duodenal digesta and faeces conforming to GN-->G1 flow. Previously undigested, masticated feed residues inserted into the dorsal rumen digesta had longer ruminal CMRT in the GN pool but not the G1 pool than did similarly inserted faecal small particles or normally ingested hay. These results support model assumptions of GN-->G1 flow within rumen digesta. The results support mechanisms proposed for the GN pool as the 'lag-rumination pool' and the G1 pool as the 'mass action turnover pool'. If further validated, rumen CMRT in cattle could be estimated from marker profiles in more easily obtained faeces to estimate ruminal CMRT required for feed evaluation systems.     

Bone marrow-derived thymic antigen-presenting cells determine self-recognition of Ia-restricted T lymphocytes.

We previously have demonstrated that in radiation-induced bone marrow chimeras, T-cell self-Ia restriction specificity appeared to correlate with the phenotype of the bone marrow-derived antigen-presenting (or dendritic) cell in the thymus during T-cell development. However, these correlations were necessarily indirect because of the difficulty in assaying thymic function directly by adult thymus transplant, which has in the past been uniformly unsuccessful. We now report success in obtaining functional T cells from nude mice grafted with adult thymuses reduced in size by treatment of the thymus donor with anti-thymocyte globulin and cortisone. When (B10 Scn X B10.D2)F1 nude mice (I-Ab,d) are given parental B10.D2 (I-Ad) thymus grafts subcutaneously, their T cells are restricted to antigen recognition in association with I-Ad gene products but not I-Ab gene products. Furthermore, thymuses from (B10 X B10.D2)F1 (I-Ab,d)----B10 (I-Ab) chimeras transplanted 6 months or longer after radiation (a time at which antigen-presenting cell function is of donor bone marrow phenotype) into (B10 X B10.D2)F1 nude mice generate T cells restricted to antigen recognition in association with both I-Ad and I-Ab gene products. Thymuses from totally allogeneic bone marrow chimeras appear to generate T cells of bone marrow donor and thymic host restriction specificity. Thus, when thymus donors are radiation-induced bone marrow chimeras, the T-cell I-region restriction of the nude mice recipients is determined at least in part by the phenotype of the bone marrow-derived thymic antigen presenting cells or dendritic cells in the chimeric thymus.