The use of polypropylene mesh in midline incision closure following gastric by-pass surgery reduces the risk of postoperative hernia

BACKGROUND: Incisional hernia is a common problem following Roux-en-Y gastric bypass for morbid obesity. PATIENTS AND MATERIALS: We report the preliminary results of nonrandomized prophylactic use of polypropylene mesh in a group of 60 consecutive patients. The patients with highest body mass index, and/or history of abdominal hernias and profound liver damage had abdominal wall reinforced with mesh during an operation. A year later the wound was assessed in all patients. RESULTS: In standard wound closure group (n=48) incisional hernia was found in 9 cases (20%). None of the patients with inserted mesh (n=12) developed hernia. The length of hospital stay in mesh group was similar to that in the nonmesh group and shorter than in patients with hernia occurrence. Mesh insertion was complicated with wound discharge in three patients. CONCLUSIONS: In our opinion prophylactic use of polypropylene mesh in bariatric patients is highly effective in postoperative hernia prevention.     

Human chronic kidney allograft rejection is accompanied by increased intraglomerular cathepsin B and L activity

Abstract The major reason for late graft losses is chronic rejection. Recently, a large number of studies have indicated that proteolytic enzymes play an important role as mediators of glomerular injury. The cysteine proteinases cathepsins B and L degrade structural matrix proteins such as type I collagen and laminin. We investigated intraglomerular protease activities in 12 patients after kidney graftectomy because of end-tage renal disease following chronic rejection. A group of 12 patients undergoing nephrectomy because of cancer served as controls using only non-involved parts of the kidney. The activities of cathepsins B and L in homogenates of isolated glomeruli were measured fluorometrically methylcoumarylamidc substrates and related to DNA content. In rejected kidney allografts we observed significantly enhanced intraglomerular cathepsin B activity and cathepsin B + L activity.     

Transfer of the distal phalange of the ring finger as a method of reconstruction of the partially amputated thumb--preliminary report]

Loss of a thumb accounts for 60% decrease of functional value of the hand, thus any attempt of it's reconstruction is a priority in the field of hand surgery. Optimal reconstructive solution for subtotal thumb amputations has not been settled. The results of partial pollicization of ring finger in 5 adult men is presented. Four patients sustained distal subtotal thumb amputation (MCP joint level), one total amputation. In three patients the distal phalange of the ring finger was transferred with the DIP joint, FDP tendon and a fragment of extensor tendon. An effective movement of a newly created thumb's IP joint was achieved in two patients. In one patient with a total thumb amputation the transfer was followed by a pollicization of the second metacarpal with remnants of proximal phalange. The postoperative course was uneventful in all of the patients. The sensitivity tested on the pulp of the transferred finger equalized to the preoperative value, the hand strength was not diminished. The cosmetic result was excellent.     

Characterization of human hepatocytes isolated from non-transplantable livers

INTRODUCTION: The successful use of hepatocytes depends on a reliable demonstration of the functional and morphological integrity of isolated cells. Herein we investigated whether the isolation and cryopreservation of primary human hepatocytes can compromise cell viability and liver-specific characteristics. MATERIAL/METHODS: Hepatocytes were isolated from encapsulated human liver segments by a modified 2-step perfusion technique. Isolated cells were Percoll-purified, cryopreserved, and stored in liquid nitrogen for 1-12 months. For rapid assessment of fresh and cryopreserve/thawed hepatocyte yield and viability, the cells were stained with trypan blue or labeled with fluorochromes. For immunocytochemical analysis, the cells were labeled with monoclonal antibodies for the presence of the following antigens and chemokines: CD3, CD45Ro, CD45Ra, CD34, CD68, CD90, CD95, CD20, HLA-DR, Ki67, PCNA, Bcl-2, p53, CXCR3, CXCR4, and SDF-1. The cells were tested for several specific functions, such as ureagenesis, energy status, MTT activity, lactate dehydrogenase leakage, and total CYP450 content. RESULTS: Assessment of both freshly isolated (Percoll-purified) and cryopreserved/thawed hepatocytes revealed a low constitutive level of contamination by non-parenchymal cells compared with crude (unpurified) preparations and tissue sections. All viable hepatocytes showed intact morphology and retained CYP450 protein, energy status, and urea synthesis. CONCLUSIONS: Modifications in hepatocyte preparations, such as depletion of dead, damaged, and nonparenchymal cells, improves cell purity, which can be adapted to further evaluation of hepatocyte immunogenicity. These data illustrate the importance and feasibility of human hepatocyte banking.     

A novel single chain I-A(b) molecule can stimulate and stain antigen-specific T cells

Multimers of soluble major histocompatibility complex class I and II molecules have proven to be useful reagents in quantifying and following specific T cell populations. This study describes the design, generation, and characterization of a novel, single chain I-A(b) molecule which utilizes a unique linker derived from the murine invariant chain. A fragment of the invariant chain, residues 58-85, binds to a region proximal to the class II peptide binding groove and stabilizes occupancy of the class II invariant chain-associated peptide. We have utilized this fragment, replacing CLIP with the Ealpha peptide sequence, to lock the attached peptide into the class II binding groove. The single chain I-A(b) molecule was recognized by a panel of conformation-sensitive, I-A(b)-specific, monoclonal antibodies. Membrane-bound and soluble forms of the single chain I-A(b) stimulated an antigen-specific T cell hybridoma, and tetramers made from soluble monomers stained these cells. The unique features of this molecule may be useful in the design of recombinant T cell receptor ligands containing peptides with low affinity for MHC.     

Blends of alkyloxy-substituted liquid-crystalline aromatic polyesters and copolyesters with poly(ethylene terephthalate)

Blends containing poly(ethylene terephthalate) (PET) and a series of alkyloxy laterally substituted liquid-crystalline copolyesters (HTO5-X series 1 ) in various ratios were prepared in the melt at 260°C by mechanical mixing. The visual and light microscopical appearance of the blends in the solid state and in the melt was found to be homogeneous for those blends which contained an aliphatic-rich HT05-X copolyester. The homogeneous appearance can be explained by a colloidal dispersion of the liquid-crystalline polymer (LCP) in PET. Obvious phase separation in the melt occurs slowly after long periods of time. Phase separation is forced by annealing at about 270°C, where a change of viscosity is observed, and by shearing the sample. Characterization of theblends by DSC experiments shows that the thermal behaviour of all blends is dominated by the phase transitions of PET and that the LC-low-phase of the HTO5-X copolyesters with a high degree of alkyloxy substitution is suppressed. The WAXS diffraction patterns of all blends contained an amorphous halo. For blends with low HTO5-X concentration, inner reflexions from the nematic sanidic phase, as exhibited by the HTO5-X copolyester, could be observed. For blends with higher HTO5-X copolyester concentration, characteristic reflexions from HTO5-X copolyester crystals could be observed. The number of X-ray reflexions of the crystalline LCP in the blend is reduced compared to that of the pure LCP.     

Improved immunoglobulin production in dialysis patients treated with recombinant erythropoietin.

Improvements in B lymphocyte function have been reported in hemodialysis patients receiving erythropoietin. The present investigation studied whether erythropoietin interferes with B cell function and the mechanisms of this effect. Antibody production by cultured peripheral blood mononuclear cells (PBMC) (7 days) from 15 dialysis patients before and during erythropoietin treatment and from 14 healthy controls was followed. IgG and IgA were formed less in the uremic group than in healthy subjects. After 8 weeks of erythropoietin (hematocrit rose from 19 to 31%) basal IgG formation by PBMC rose from 304 +/- 83 to 566 +/- 49 ng/ml (p less than 0.02), while IgA production rose from 380 +/- 121 to 563 +/- 362 ng/ml (p less than 0.01). IgM production, which appeared to be normal in uremia, remained unchanged during erythropoietin treatment. Production of IgG and IgA stimulated by pokeweed-mitogen was subnormal in uremia, but improved under erythropoietin therapy. To establish whether erythropoietin acted by itself or through correction of the renal anemia, healthy PBMC were directly incubated with 2 U/ml of erythropoietin. Under these conditions production of IgG (+19%), IgA (+28%), and IgM (+32%) was enhanced. Taken together these data indicate a direct stimulant effect of erythropoietin on B lymphocytes in end-stage renal failure.     

Therapeutic Vaccines for Cervical Cancer

Human papillomavirus (HPV) infection is associated with transformation and clonal expansion of infected epithelial cells, resulting in the production of a benign growth, i.e. a wart. Recently, however, HPV has emerged as the primary causative agent of cervical carcinoma, malignancy being associated with the presence of the viral genome (predominantly genotypes 16 and 18) in cancerous cells. The only HPV proteins reliably expressed in neoplastic lesions are the 'oncogenic' E6 and E7 proteins, that serve both as tumour-specific markers and potential targets for immunotherapeutic intervention. As intracellular (nuclear) proteins, the E6 and E7 gene products may be hidden from the humoral immune response. Attention has thus focused on the generation of a vaccine capable of inducing or stimulating a cellular immune response to HPV 16 and HPV 18 E6 and E7. Vaccine development has been constrained by the absence of an appropriate animal model, the oncogenic nature of E6 and E7 and technical difficulties associated with detection of cytotoxic T cell responses to these antigens. Despite these difficulties, vaccine strategies have now been devised based on immunisation with synthetic peptide, whole protein and a vaccinia virus recombinant. Phase I/II human clinical trials have been initiated, and preliminary results have demonstrated the induction of specific cellular immune responses after immunisation. The HPV-associated neoplasia in cervical cancer represents an excellent target for therapeutic intervention because the tumour-associated antigens are so clearly defined. As such, it provides an appropriate model for establishing the general principles of cancer immunotherapy in humans.     

Effect of endurance and sprint exercise on the sensitivity of glucose metabolism to insulin in the epitrochlearis muscle of sedentary and trained rats

Summary The effects of two types of acute exercise (1 h treadmill running at 20 m· min^–1, or 6 × 10-s periods at 43 m · min^–1, 0° inclination), as well as two training regimes (endurance and sprint) on the sensitivity of epitrochlearis muscle [fast twitch (FT) fibres] to insulin were measured in vitro in rats. The hormone concentration in the incubation medium producing the half maximal stimulation of lactate (la) production and glycogen synthesis was determined and used as an index of the muscle insulin sensitivity. A single period of moderate endurance as well as the sprint-type exercise increased the sensitivity of la production to insulin although the rate of la production enhanced markedly only after sprint exercise at 10 and 100 U· ml^–1 of insulin. These effects persisted for up to 2 h after the termination of exercise. Both types of exercise significantly decreased the muscle glycogen content, causing a moderate enhancement in the insulin-stimulated rates of glycogen synthesis in vitro for up to 2 h after exercise. However, a significant increase in the sensitivity of this process to insulin was found only in the muscle removed 0.25 h after the sprint effort. Training of the sprint and endurance types increased insulin-stimulated rates of glycolysis 24 h after the last period of exercise. The sensitivity of this process to insulin was also increased at this instant. Both types of training increased the basal and maximal rates of glycogen snythesis, as well as the sensitivity of this process to insulin at the 24^th following the last training session. It was concluded that in the epitrochlearis muscle, containing mainly FT fibres, both moderate and intensive exercise (acute and repeated) were effective in increasing sensitivity of glucose utilization to insulin. Thus, the response in this muscle type to increased physical activity differs from that reported previously in the soleus muscle, representing the slow-twitch, oxidative fibres in which sprint exercise did not produce any changes in the muscle insulin sensitivity.     

Axonal collateral branching of neurones in the inferior olive projecting to the cerebellar paramedian lobule in the rabbit

The double fluorescent retrograde technique was employed to examine the distribution of the inferior olive (IO) neurones projecting to the cortex of the rostral and caudal parts of the paramedian lobule (PML) in the rabbit cerebellum, known to be the face-forelimb and hindlimb receiving areas, respectively. Moreover, this technique was also used to investigate the possibility that IO projections reaching these two somatotopically non-homologous PML regions are collaterals of the same axones. No other reports have addressed this question. After non-overlapping unilateral injections of the cytoplasmic tracer fast blue (FB) and the nuclear dye diamidino yellow (DY) into the rostral and caudal PML, respectively, numerous single FB- or DY-labelled cells were found in the defined regions of the contralateral IO. These regions showed considerable overlap, apart from the dorsal accessory olive where a clear spatial separation of labelled cell groups was observed. Furthermore, double FB + DY-labelled neurones (n = 310) were seen in the medial accessory olive, the dorsal and ventral laminas of the principal olive, in the dorsomedial cell column and the beta nucleus. It suggests that IO neurones may branch to supply the two functionally different PML regions and in this way participate in the mechanisms of forelimb-hindlimb coordination.