Initial experience with transvaginal incisional hernia repair.

INTRODUCTION: Natural orifice surgery has evolved from a preclinical setting into a common occurrence at the University of California San Diego (UCSD). With close to 40 transvaginal cases, we have become comfortable with this technique and are exploring other indications. One of the perceived advantages in natural orifice surgery is the potential reduction in the incidence of hernia formation. Patients with abdominal wall hernias may be at increased risk of forming additional hernias at incision sites. In addition, patients with recurrent incisional hernias may, likewise, be at increased risk. We believe that reducing or eliminating abdominal wall incisions may be of benefit in the repair of abdominal wall hernias. Here, we describe what we believe to be the first natural orifice transluminal endoscopic surgical (NOTES) approach to the repair of an abdominal wall hernia. METHODS: The patient is a 38-year-old female with a painful recurrent umbilical hernia, previously repaired 8 years prior with a polypropylene-based mesh. The patient underwent a transvaginal recurrent umbilical hernia repair with one other 5-mm port in the abdomen for safety. RESULTS: The patient had no intraoperative or postoperative complications. At 5 months follow up, the patient had no complaints, no evidence of hernia recurrence, and was very pleased with her result. CONCLUSIONS: The repair of primary and incisional hernias of the ventral abdominal wall via a transvaginal approach is technically feasible, and the result of our initial case was exceptional. However, there are still significant obstacles which must be addressed before this approach can be widely utilized. These obstacles include safe entrance into the abdominal cavity via a transvaginal approach, the proper mesh to be placed during the repair, and the risk of infection.

Does weight loss improve incontinence in moderately obese women?

The aim of this study was to evaluate the effect of weight reduction on urinary incontinence in moderately obese women. This prospective cohort study enrolled moderately obese women experiencing four or more incontinence episodes per week. BMI and a 7-day urinary diary were collected at baseline and on the completion of weight reduction. The study included 10 women with a mean (+/-SD) baseline BMI of 38.3 (+/-10.1) kg/m2 and 13 (+/-10) incontinent episodes per week. Participants had a mean BMI reduction of 5.3 (+/-6.2) kg/ m2 (P < 0.03). Among women achieving a weight loss of > or = 5%, 6/6 had > or = 50% reduction in incontinence frequency compared to 1 in 4 women with < 5% weight loss (P < 0.03). Incontinence episodes decreased to 8 (+/-10) per week following weight reduction (P < 0.07). The study demonstrated an association between weight reduction and improved urinary incontinence. Weight reduction should be considered for moderately obese women as part of non-surgical therapy for incontinence.

Cutting edge: proteasome involvement in the degradation of unassembled Ig light chains.

Several studies on disposal of nonsecreted Ig L chains have identified the endoplasmic reticulum as the site of degradation. Here, we examine degradation of a nonsecreted Ig L chain, T15L, and an experimentally endoplasmic reticulum-retained secretion-competent L chain, D16L, in the absence of H chains. We demonstrate that 1) degradation is specifically impaired by the proteasome-specific inhibitors carboxybenzyl-leucyl-leucyl-leucine vinyl sulfone (Z-L3VS) and lactacystin, 2) L chain degradation occurs early in the biosynthetic pathway, and 3) degradation does not require vesicular transport. Our findings indicate that previous assertions of L chain disposal within the endoplasmic reticulum must be modified. To our knowledge, we provide the first direct evidence supporting a new paradigm for removal of nonsecreted Ig L chains via dislocation to cytosolic proteasomes.

Germline structure and differential utilization of Igha and Ighb VH10 genes.

Ab heavy chains encoded by mouse VH10 genes have been of particular interest due to their frequent association with DNA binding. We reported previously that VH10 sequences are over-represented in the preimmune repertoire considering the apparent number of germline-encoded VH10 gene segments. In this report, we show that the VH10 family consists of three and two germline genes in the Igha and Ighb haplotypes, respectively. The complete nucleotide sequences of these five genes, including promoters and recombination signal sequences, were determined and allow unambiguous assignment of allelic relationships. The usage of individual VH10 genes varied significantly and ranged from 0.2% to an extraordinary 7.2% of the VH genes expressed by splenic B cells. Since the promoter and recombination signal sequence elements of all five VH10 genes are identical, we suggest that the few amino acid differences encoded by these five germline VH10 genes determine their representation in the preimmune repertoire. Rearrangements of the most frequently used VH10 gene have an apparent bias for histidine at position 95 of complementarity-determining region-3 (CDR3). These CDR3s are also biased for asparagine, an amino acid associated with the CDRs of DNA binding Abs. Together, these results suggest that high VH10 gene use is the result of B cell receptor-mediated selection and may involve DNA and/or ligands that share antigenic features with DNA.

Harmful somatic mutations: lessons from the dark side.

The ability of somatic mutation to modify the course of an immune response is well documented. However, emphasis has been placed almost exclusively on the ability of somatic mutation to improve the functional characteristics of representative antibodies. The harmful effects of somatic mutation, its dark side, have been far less well characterized. Yet evidence suggests that the number of B cells directed to wastage pathways as a result of harmful somatic mutation probably far exceeds the number of cells whose antibodies have been improved. Here we review our recent findings in understanding the structural and functional consequences of V-region mutation.

Rearrangement and selection in the developing Vkappa repertoire of the mouse: an analysis of the usage of two Vkappa gene segments.

Detailed analysis of the rearrangement and expression of two mouse Vkappa genes has been used to examine B cell repertoire development. The Vkappa1-A gene is used by a large proportion (9.6%) of splenic B cells in the adult primary repertoire, whereas the Vkappa22 gene is used at a much lower frequency (0.16%). Consistent with these results, quantitative PCR (Q-PCR) assays revealed that the number of splenic B cells with rearranged Vkappa1-A genes is much greater than the number with rearranged Vkappa22 genes. Q-PCR was also performed on both normal bone marrow pre-B cells and transformed pre-B cells induced to rearrange their kappa loci at high frequency. In contrast to splenic B cell rearrangements, the numbers of Vkappa1-A and Vkappa22 rearrangements in pre-B cells differ by only two- or threefold, suggesting that the intrinsic rearrangement frequencies of these two Vkappa genes are not significantly different. Further evidence of disproportionate selection was obtained by comparing the percentages of productive rearrangements amplified from genomic splenic DNA. Sequence analysis showed 84% (37 of 44) of the Vkappa1-A rearrangements but only 57% (29 of 51) of the Vkappa22 rearrangements to be in-frame. Together these results suggest that B cells expressing Vkappa1-A-encoded light chains are preferentially selected either in the periphery or in the transition from pre-B to B cell. Sequence data also reveal a surprisingly restricted diversity of VJ junctions, apparently due to biases introduced by the rearrangement mechanism.

Differential effects of interleukin-1 alpha and interleukin-1 beta on human peripheral blood eosinophils.

Interleukin-1 (IL-1) plays a major role in the response to infection, inflammation, and immunological challenge. Eosinophils participate in the host response to parasitic infection and allergic and hypersensitivity diseases. The role of IL-1 in these disease states has not been extensively explored. We have reported that purified human monocyte derived IL-1 (mIL-1), a mixture of the two IL-1 forms but predominantly consisting of IL-1 beta, modulates eosinophil oxidative metabolism and enzyme secretion. Although the two major species of IL-1 (IL-1 alpha and IL-1 beta) have identical specific activities on T cells, we now report the selective effects of human recombinant IL-1 (hrIL-1) alpha and hrIL-1 beta on eosinophil function. Whereas hrIL-1 beta caused a significant increase in arylsulfatase secretion (235.4 +/- 29% of resting secretion, P less than or equal to .01) and beta-glucuronidase secretion (135.8 +/- 9.6% of resting secretion, P less than or equal to .02) similar to our experience with mIL-1, hrIL-1 alpha had no effect on enzyme secretion. However, a mixture of hrIL-1 alpha and hrIL-1 beta reproduced the ability of mIL-1 to inhibit the oxidative response to suboptimal doses of phorbol myristate acetate (PMA). When eosinophils were separated into subpopulations by density gradients, we found that eosinophil responses to IL-1 differed among the populations. These results suggest that eosinophil subpopulations respond selectively to each form of IL-1.

Modulation of human peripheral blood eosinophil function by tumor necrosis factor-alpha.

Eosinophils are important effectors in helminthic parasitic infection. Tumor necrosis factor (TNF-alpha) has been implicated as a mediator in the host response to parasitic infection and enhances eosinophil-mediated helminthotoxicity. We have examined the direct effects of recombinant human (rh) TNF on eosinophil functions of degranulation and oxidative metabolism. This report describes the minimal effects of rhTNF-alpha on eosinophil superoxide anion generation and enzyme secretion, which do not satisfactorily explain the observed increases in helminthotoxicity. In contrast to other cell types, eosinophils are unique in their differential responses to interleukin-1 beta and TNF.

Interaction of IL 1 and TPA in modulation of eosinophil function.

The tumor co-promotor TPA is believed to enhance a wide variety of cellular processes by interacting with protein kinase C. Interleukin (IL 1) is a family of highly active molecules which augments the host response to infection. We have explored the interactions of these activators of cell function on the modulation of selected eosinophil functions. The effects of purified monocyte-derived IL 1 on the eosinophil functions of oxidative metabolism (as measured by superoxide anion production) and degranulation (as measured by release of the granular enzymes arylsulfatase and beta-glucuronidase) have been examined. Superoxide anion production by eosinophils stimulated with standard doses of the stimulant phorbol myristic acetate (TPA) (1 microgram/ml) was augmented approximately 20% by preincubation with IL 1. However, IL 1 alone had no effect on superoxide anion production. At suboptimal doses of TPA, there was a dose-dependent inhibition of superoxide anion production in the presence of IL 1. Calcium ionophore (2 X 10(-7) M) markedly enhanced superoxide anion production elicited by 0.1 ng/ml of TPA, but had only modest effects in the absence of TPA. When IL 1 was added to eosinophils stimulated by TPA in the presence of calcium ionophore, there was a dose-dependent increase in superoxide anion production. In contrast to other cell types, degranulation as measured by the release of arylsulfatase and beta-glucuronidase was not elicited by the addition of TPA (1 microgram/ml). Although calcium ionophore (2 X 10(-6) M) caused enzyme release (24.2% release of beta-glucuronidase, 29.4% release of arylsulfatase), this release was inhibited by the addition of TPA. The addition of IL 1 alone caused an approximate twofold increase in enzyme release, but pretreatment with IL 1 (1 U) reduced ionophore-mediated degranulation (p less than or equal to 0.05). Studies employing purified monocyte IL 1 were confirmed by recombinant IL 1-beta. These studies demonstrate for the first time that eosinophil function is modulated by IL 1. IL 1 may also modify the response of eosinophils to other stimuli such as ionophore and TPA. Because TPA is known to act by direct binding to protein kinase C, these studies also demonstrate that, in eosinophils, activation of protein kinase C by phorbol esters may augment one cellular function (oxidative metabolism) while inhibiting another cellular function (degranulation). Similarly, phorbol esters may act synergistically with calcium ionophore in regulation of one function (oxidative metabolism) and act antagonistically with another function (degranulation). The concept that IL 1 uniformly enhances cell function may need to be re-evaluated.

Effect of paraoxon on erythrocyte metabolism as measured by oxygen uptake in vitro.

1. Oxygen consumption in vitro and persistence in the general circulation of rabbit erythrocytes treated with the cholinesterase inhibitor paraoxon were determined.2. Paraoxon in vitro reduced oxygen consumption below a measureable level within 2 hours. By contrast, the metabolic inhibitor N-ethylmaleimide (NEM) produced complete inhibition within 15 minutes.3. Erythrocytes from rabbits orally dosed with parathion also exhibited marked depression of oxygen consumption.4. Glutathione (GSH) restored oxygen uptake to pretreatment levels within 15 min in erythrocytes previously inhibited with NEM or paraoxon.5. Erythrocytes treated with NEM were rapidly removed from the general circulation while paraoxon treated cells were removed at a rate comparable to untreated cells.