The increased angiogenic capacity and decreased inflammatory response when a mesh is used in combination with an omental flap. A prospective experimental study

BACKGROUND

The use of a surgical mesh for abdominal wall reconstruction is well established and has been used for long with minor complications, whereas the omental flap has been used for decades in reconstructive surgery.

AIM

To demonstrate the increased angiogenic capacity and the reduced inflammatory markers of a synthetic mesh when used in combination with an omental flap. Furthermore, we compare two independent meshes when used alone or in combination with the omental flap.

MATERIALS AND METHODS

Twenty-eight rats were included in the study. To determine the effect of using an omental flap under two different meshes, the animals were separated into four groups, i.e., group A (flap + mesh 1), group B (flap + mesh 1 + silicone), group C (flap + mesh 2), and group D (flap + mesh 2 + silicone). A silicone sheet was placed as a barrier between the mesh and the flap. All groups were sacrificed 8 weeks post-operatively.

RESULTS

The use of a silicone sheet barrier between any of the two synthetic meshes and the omental flap in an abdominal wall defect is accompanied by a markedly reduced angiogenesis in terms of a cluster of differentiation (CD)-34 (p < 0.001) and factor VIII (p = 0.0012) and by increased inflammatory response CD-68 (p = 0.0024) and visual scoring (p < 0.001).

CONCLUSIONS

Τhe increased angiogenic capacity and the reduced inflammatory markers of a synthetic surgical mesh when used in combination with an omental flap make it a useful option in the reconstruction of an abdominal wall defect on a large or contaminated wound.

Therapeutic options and results for the management of minimally invasive carcinoma of the breast: influence of axillary dissection for treatment of T1a and T1b lesions

BACKGROUND

Axillary dissection has maintained a role of primacy for the surgical therapy of invasive carcinoma of the breast for many years. More recently, early (T1) minimally invasive carcinoma of the breast has been diagnosed with increasing frequency, and the necessity of axillary dissection for sampling purposes in these small tumors has been questioned, based primarily on the finding of low rates of axillary metastases.

STUDY DESIGN

The Rhode Island State Tumor Registry records of 1,126 patients with T1a or T1b tumors were examined to assess the effect of axillary dissection on patient outcome. These data span 9 years (1985 to 1992) with a median follow-up duration of 64 months. Five-year overall, disease-free, and breast cancer-specific (determinate) survival were determined according to treatment modality. Axillary node positivity was calculated for patients with minimally invasive carcinoma of the breast who underwent axillary dissection. Multivariate statistical methods were used to provide adjustment for known confounding prognostic variables.

RESULTS

Omission of axillary dissection occurred in 157 cases and correlated with reductions in overall, disease-free, and breast cancer-specific survival (p < .001 in all cases). Nodal status significantly influenced disease-free survival in minimally invasive carcinoma of the breast (90 percent node-negative compared with 76 percent node-positive, p = .02). Nodal positivity was evident in 18.2 percent of patients undergoing axillary dissection for minimally invasive carcinoma of the breast (9.8 percent for T1a, 19.4 percent for T1b, p = .01). In multivariate analysis, the performance of axillary dissection with breast conservation or modified radical mastectomy were independent predictors of overall survival, as well as disease-free and breast cancer-specific survival.

CONCLUSIONS

A significant number of patients with small (less than or equal to 1 cm) invasive tumors of the breast will have axillary metastases at the time of diagnosis. Omission of axillary dissection in these patients was associated with significant impairment of overall, disease-free, and breast cancer-specific survival. Axillary dissection should continue to be a standard approach for the surgical therapy of all patients with invasive carcinoma of the breast, regardless of tumor size.

Survival of patients with stage IA malignant melanoma

There is ongoing clinical research on prognostic parameters relevant to stage IA melanoma. The object is to identify those factors associated with an increased risk of recurrence. The charts of 197 patients first treated at our Institute between 1980 and 1992 along with 62 patients referred for follow-up or treatment of recurrent disease, all having been initially diagnosed with stage IA disease, were reviewed. Only one patient (0.5%) of those first treated at our Institute manifested recurrence and this was a local recurrence. No statistically significant differences were found between patients who relapsed and those who did not with regard to lesion thickness, level of invasion, evidence of ulceration, location of the primary lesion, gender, or age. Generally, stage IA melanomas have excellent prognosis. However, there are patients who experience recurrent and metastatic disease. At the present time, there are no reliable indicators available for use in predicting which patients are at risk.

Thyroid autoantibodies in the subsets of lupus erythematosus: correlation with other autoantibodies and thyroid function

Thirty four sera from: 12 patients with Systemic Lupus Erythematosus (SLE), 9 with Subacute Cutaneous Lupus Erythematosus (SCLE) and 13 with Discoid Lupus Erythematosus (DLE) (disseminatus 3, localised 10) were tested for the presence of: (a) anti-thyroglobulin and anti-microsomal autoantibodies (b) anti-Sm/RNP, anti-doublestranded. DNA (anti-ds. DNA), anti-single-Stranded. DNA (anti-ss. DNA), anti-cardiolipin (anti-Cl), anti-SSA, anti-SSB, Antinuclear Antibodies (ANA). T3, T4, TSH levels were also determined. Five patients with SLE (41.6%), 4 with SCLE (44.4%), and 2 with DLE (15.3%) had thyroid autoantibodies and only three of the 41 controls (7.3%). Five patients (14.7%), especially from SLE and SCLE groups, had biochemical hypothyroidism whereas only one had hyperthyroidism. Statistical evaluation for the possible coexistence of thyroid autoantibodies with a panel of lupus characteristic autoantibodies, revealed highly significant correlations with anti-Sm/RNP, IgG (p = 0.003) and anti-ds. DNA, IgM (p = 0.012). It may be concluded, that not only SLE but also SCLE predisposes to autoimmune thyroid disease and the prevalence of the latter is related to a great extent to the subset of the LE spectrum. From these results and from the inhibition experiments, it seems that some of the specific mono- or polyclonal autoantibodies may be multiple organ reactive.

Autoreactive T cells from MRL-lpr/lpr mice secrete multiple lymphokines and induce the production of IgG anti-DNA antibodies

The study of T cells in individuals with systemic lupus erythematosus has been limited because a specific marker for the disease has not been identified. To approach this issue, we isolated autoreactive T cell clones from lupus-prone MRL mice, a strain that develops an accelerated form of lupus. These CD4+ T cell clones grew spontaneously from unimmunized mice, and were maintained in culture by intermittent stimulation with syngeneic antigen presenting cells in the absence of exogenous antigen. One autoreactive T cell clone, termed ARTC-1, previously reported to have atypical MHC requirements for activation (both I-Ak and I-Ek were required) and to stimulate B cell proliferation and Ig production in vitro, was found to have an unrestricted pattern of lymphokine secretion. Following stimulation, it produced IL-4, IFN-gamma and IL-2. ARTC-1 induced B cell proliferation both by cell contact and through secretion of soluble lymphokines. B cell proliferation by cell-cell contact was MHC restricted in a manner analogous to ARTC-1 activation by APCs; the B cell response was inhibited by both anti-I-Ak and anti-I-Ek antibodies. The ARTC-1 B cell interaction was also found to result in the production of IgG autoantibodies. These observations suggest that cells such as ARTC-1, if unregulated, could lead to B cell stimulation and autoantibody production in vivo, in the absence of exogenous stimulation. Furthermore, IFN-gamma production by ARTC-1 could also result in enhanced class II expression, leading both to additional T-B cell interactions and to T cell interactions with endogenous cells capable of expressing class II antigens in other organs.

Monoclonal IgM with unique specificity to gangliosides GM1 and GD1b and to lacto-N-tetraose associated with human motor neuron disease

IgM lambda monoclonal antibodies in two patients with motor neuron disease showed the same unique antigenic specificity. They bound to gangliosides GM1 and GD1b and to lacto-N-tetraose-BSA. By immunofluorescence microscopy they bound to central and peripheral nerve tissue and to motor end-plates at the neuromuscular junction. Sera from control subjects did not contain antibodies of similar specificity. Monoclonal IgMs with the same unique specificity could be responsible for motor neuron disease in some patients with monoclonal gammopathies.