Metabolic adaptation of MDCK cells to different growth conditions: effects on catalytic activities of central metabolic enzymes.

Lactate and ammonia are the most important waste products of central carbon metabolism in mammalian cell cultures. In particular during batch and fed-batch cultivations these toxic by-products are excreted into the medium in large amounts, and not only affect cell viability and productivity but often also prevent growth to high cell densities. The most promising approach to overcome such a metabolic imbalance is the replacement of one or several components in the culture medium. It has been previously shown that pyruvate can be substituted for glutamine in cultures of adherent Madin-Darby canine kidney (MDCK) cells. As a consequence, the cells not only released no ammonia but glucose consumption and lactate production were also reduced significantly. In this work, the impact of media changes on glucose and glutamine metabolism was further elucidated by using a high-throughput platform for enzyme activity measurements of mammalian cells. Adherent MDCK cells were grown to stationary and exponential phase in six-well plates in serum-containing GMEM supplemented with glutamine or pyruvate. A total number of 28 key metabolic enzyme activities of cell extracts were analyzed. The overall activity of the pentose phosphate pathway was up-regulated during exponential cell growth in pyruvate-containing medium suggesting that more glucose-6-phosphate was channeled into the oxidative branch. Furthermore, the anaplerotic enzymes pyruvate carboxylase and pyruvate dehydrogenase showed higher cell specific activities with pyruvate. An increase in cell specific activity was also found for NAD(+)-dependent isocitrate dehydrogenase, glutamate dehydrogenase, and glutamine synthetase in MDCK cells grown with pyruvate. It can be assumed that the increase in enzyme activities was required to compensate for the energy demand and to replenish the glutamine pool. On the other hand, the activities of glutaminolytic enzymes (e.g., alanine and aspartate transaminase) were decreased in cells grown with pyruvate, which seems to be related to a decreased glutamine metabolism.

Cell-cell-neighborhood relations in tissue sections--a quantitative model for tissue cytometry.

Physical interactions between different cell types are a requirement for the initiation and maintenance of immune responses. The distribution pattern of cells within a tissue may result from specific cell-cell-interactions or random distribution. Tissue architecture, degree of inflammation, frequencies of cells, number of contact partners, cell type, and size as well as cell movement and contact time determine the distribution of cells within tissues. We developed a matrix model to determine the degree of expected random distribution of two cell types (A and B) and cell-cell-contacts within tissue sections. The model predictions were compared with experimental data derived from immunofluorescence microscopy. We implemented a computer algorithm for automatic image analysis to visualize and quantify cell-cell-neighborhood relations. Using the number of cells type A (a), the total cell number (t) and the mean number of cells that are in contact with cells type B (c(B)), the ratio of cells type B in contact with cells type A can be described by b(A)/b = 1- (1- (a/t))[symbol: see text]c(B). We applied the model system to investigate the distribution of Foxp3(+) regulatory T cells with Ki-67(+) proliferating cells within mouse tissue sections. The matrix model provides a tool to describe the expected distribution of two different cell types and their cell-cell-contacts within tissues. Comparing the degree of expected random distribution with experimental data might help to propose functional cell-cell-interactions in tissue sections.

Breast conservation therapy after augmentation mammaplasty: is it appropriate?

Breast conservation therapy, consisting of lumpectomy, axillary node dissection, whole-breast irradiation, and a boost to the tumor bed, is an increasingly popular option for the treatment of breast cancer. Among patients with stage I and stage II disease, breast conservation therapy yields survival rates equivalent to those for mastectomy. The cosmetic results of radiotherapy are usually good, and this approach preserves an intact, sensate breast. Most studies on breast conservation therapy, however, have been performed in nonaugmented patients. Relatively little has been published regarding breast conservation therapy in the presence of silicone implants. Between 1981 and 1994, we treated 33 augmented patients with breast conservation therapy. Among 26 individuals for whom complete follow-up data were available, 17 (65 percent) developed significant capsular contracture on the irradiated side. Thus far 8 patients with radiation-induced contracture have undergone corrective surgery. In our experience, augmented breast cancer patients treated with breast conservation therapy have less satisfactory cosmetic results than nonaugmented women. In addition, mammographic follow-up, critical for identifying local recurrence, may be impaired by the presence of an implant and capsular contracture. On the basis of these considerations, breast conservation therapy may be less than optimal in augmented cancer patients unless explantation is performed before treatment.

The fate of breast implants: a critical analysis of complications and outcomes.

Complications and outcomes were monitored following the implantation of 1655 breast implants over a 15-year period. Smooth, polyurethane, and textured implants were used in a variety of clinical settings. The time course of capsular contracture was analyzed by the Kaplan-Meier method. Regardless of implant type or indication for surgery, the probability of contracture increased with time. Polyurethane-covered implants were associated with a significant reduction in the risk of contracture for at least 7 years following implantation. Smooth and textured silicone implants had contracture rates similar to each other, and the particular type of surface texturing (Biocel versus Siltex) was of no consequence. Contracture was more common following breast reconstruction and implant replacement than after augmentation mammaplasty and was not affected by filler material or implant size. Implant position did not alter the risk of contracture after augmentation; tissue expansion did not affect the risk of contracture after breast reconstruction. Infections were unusual but most common after reconstruction and unrelated to surface texture or filler material. Skin wrinkling was more frequent with saline implants and in the presence of surface texturing. Implant rupture was rare, with an incidence of 1 per 760 implant-years. Implant-associated connective-tissue disease was noted in only one individual, an incidence of 1 per 3801 implant-years.

Extended skin island delay of the unipedicle TRAM flap: experience in 35 patients.

A technique to surgically delay a single-pedicle TRAM flap is described. This extended skin island delay essentially divides the unipedicle TRAM flap into two stages separated by 1 week. Experience with this flap in 35 patients is reported. On the basis of this experience, we believe that the extended skin island delayed TRAM flap should be considered a safe and reliable alternative to double muscle pedicle and free tissue transfer in high-risk patients.

Surgical alteration of appearance among primitive societies in New Guinea.

On the remote island of New Guinea, hundreds of primitive cultures flourish as they have for centuries, virtually unaffected by outside influences. Among these tribes, practices involving intentional surgical alteration of appearance are common. While these practices do not exactly constitute cosmetic surgery as we define it, they have some interesting parallels with modern plastic surgery. These customs have been observed by anthropologists for decades, but relatively little has been written about them, and nothing has been recorded from the perspective of the plastic surgeon. This paper reviews descriptions made by early anthropologists in New Guinea, records personal observations which I made during two recent trips to the area, and illustrates these customs with photographs of contemporary tribespeople. An examination of these unusual practices provides insight into the underlying impulses that motivate people from radically different cultures to intentionally alter their appearance.

An in vivo study of the effect of various breast implant filler materials on mammography.

Silicone breast implants have the potential to interfere with mammography through a variety of different mechanisms. One important factor is the radiopacity of the implant. A comparison was made of the effect of six different implant filler materials on visualization of known breast lesions in a living subject. The materials studied were normal saline, a triglyceride solution, silicone gel, a solution of 50% polyvinylpyrrolidone (PVP) in saline, a solution of 10% PVP in saline, and a solution of 2.5% PVP in glycerine. The ease with which known breast lesions could be identified through different materials varied dramatically. The poorest visualization was through the silicone gel-filled implant. The best visualization was through the prosthesis containing a triglyceride solution. Physical density, atomic number, and electron density are the factors which determine the radiopacity of materials used to fabricate breast implants. Radiopacity, in turn, affects the ease with which breast lesions can be imaged in vivo. The radiologic characteristics of filler materials will be an important consideration in the design of future breast implants.

Knowledge, concern, and satisfaction among augmentation mammaplasty patients.

Eighty-five patients with augmentation mammaplasty were surveyed. Patients were polled about knowledge of risks, level of concern, awareness of media publicity, incidence of complications, and degree of satisfaction with breast implants. Sixty-one percent of the patients were satisfied or very satisfied with implants, whereas 32% were somewhat or very unsatisfied. Level of satisfaction was not related to knowledge of risks, but did correlate with having experienced side effects or complications. Virtually all patients were aware of recent media publicity about implants, and 90% of women perceived the publicity to be negative. Seventy-five percent of the patients expressed concern about implant safety. Even after exposure to negative publicity, however, < 10% of those surveyed regret having had the surgery and only 6% indicated they would like their implants removed. Overall, patients with augmentation mammaplasty perceive the benefits of implants greatly outweigh the risks.

Factors affecting mammographic visualization of the breast after augmentation mammaplasty.

OBJECTIVE: To measure the effect of various parameters on mammographic visualization of the breast after augmentation mammaplasty. DESIGN: Preoperative and postoperative mammography was performed in patients undergoing augmentation mammaplasty. The area of breast tissue visualized on each film was measured. Changes in the area visualized were correlated with a variety of different parameters. SETTING: The Breast Center, Van Nuys, Calif, a free-standing multidisciplinary breast diagnostic and treatment facility. PATIENTS: The 68 women (126 breasts) represent a consecutive sample of patients undergoing augmentation mammaplasty for whom preoperative and postoperative mammograms were available. MAIN OUTCOME MEASURES: Area visualized was correlated with degree of capsular contracture, implant position, type of mammography, preoperative breast size, implant size, and implant type. RESULTS: The major factor affecting mammography is capsular contracture. Little or no capsular contracture results in a 30% reduction in the area visualized; moderate or severe contracture results in a 50% reduction. Other important factors include implant position (improved visualization with implant beneath pectoral muscle) and type of mammography performed (slightly more tissue seen with displacement technique). Very small preoperative breast size yields increased visualization. Implant size and type have little or no effect. CONCLUSIONS: In most women with breast implants, there is a decrease in measurable breast tissue on the postaugmentation mammogram. Capsular contracture and implant position exert a profound effect; type of mammography performed and preoperative breast size are also significant.

Reduction mammaplasty following radiation therapy for breast cancer.

This report describes an unusual case in which reduction mammaplasty was performed following radiation therapy for breast cancer. While healing was significantly prolonged (compared with the nonirradiated contralateral breast), the final result was satisfactory from both the functional and the aesthetic standpoint. Women with prior radiation therapy may be considered candidates for reduction mammaplasty. Patients should be warned of the increased risks of wound complications, the likelihood of delayed healing, and the possibility of pigmentation changes in the grafted nipple-areola complex. We elected to transpose the nipple as a full-thickness graft, but consideration also might be given to use of an inferiorly based pedicle flap.

An improved technique for creation of the inframammary fold in silicone implant breast reconstruction.

A "lipo-fascial" flap is described for creation of the inframammary fold in patients undergoing breast reconstruction with silicone implants. We have employed this technique in 13 patients. The fold has been enhanced in all cases, and we have not encountered any significant complications. This technique is a useful adjunct to breast reconstruction with a silicone implant, and we recommend that it be considered in appropriate patients.

Breast cancer diagnosis and prognosis in women following augmentation with silicone gel-filled prostheses.

62 healthy women were studied mammographically before and after augmentation mammoplasty. Postaugmentation mammograms were done using both the implant compression and implant displacement technique. The amount of visualisable tissue was measured in all films before and after augmentation. We concluded: State-of-the-art film-screen mammography is extremely difficult to obtain in most patients augmented with silicone-gel-filled prostheses. On average, there is a decrease in measurable visualised breast tissue after augmentation mammoplasty with silicone-gel-filled prostheses. The area of mammographically measurable tissue is no different whether smooth or textured implants are used. Textured implants are less likely to form an early capsular contracture and are therefore preferred. However, the cancer-causing potential of polyurethane in humans is currently unknown. Anterior breast tissue is generally seen better with displacement mammography; posterior breast tissue with compression mammography. Better films are generally obtained when the implant is in the subpectoral position rather than subglandular. The more severe the capsular contracture, the poorer the mammogram. In addition 42 previously augmented patients developed breast carcinomas an average of 8.4 years after augmentation with silicone-gel-filled implants; 95% had palpable lesions (only 60% of which could be seen on mammography), 90% had infiltrating carcinomas, 45% had metastases to axillary nodes, and 7 patients have recurred, 5 of whom have died. We concluded: Augmented women who develop breast cancer are similar, in terms of tumour size and nodal positivity, to non-augmented breast cancer patients who present with palpable masses. When compared with non-augmented women whose breast cancers are found with screening mammography, augmented patients with breast cancer present with a higher percentage of invasive lesions and involved axillary lymph nodes, resulting in a poorer prognosis. The 40% false negative rate for mammography in this series is unduly high and alarming. Augmentation mammoplasty with silicone-gel-filled implants should be discouraged in women with a high risk of developing breast cancer.

Current status of breast reconstruction after mastectomy.

Breast reconstruction after mastectomy can make an important contribution to the quality of life of women with breast cancer. Reconstruction eliminates the need for a cumbersome external prosthesis, allows greater freedom in the selection of clothing styles, and makes a woman more comfortable undressing in front of others. Reconstruction also reduces anxiety and depression and helps a woman regain a sense of wholeness and femininity. Advances in breast reconstruction include improved types of implants, use of autogenous tissues, and refinements in nipple reconstruction. This article summarizes the "state of the art" in breast reconstruction, the various surgical techniques available, their indications, advantages, and potential drawbacks.

Comparative experience with smooth and polyurethane breast implants using the Kaplan-Meier method of survival analysis.

Smooth-walled silicone implants have been widely used in breast surgery. Capsular contracture, causing undesirable firmness and spherical deformity, has been a common problem. Recent studies suggest that polyurethane-covered breast implants are associated with a lower incidence of capsular contracture. The statistical methodology employed in some of these studies, however, may be subject to criticism. Between July of 1984 and June of 1990 (72 months), 427 polyurethane breast implants were used in 279 patients and 439 smooth prostheses were used in 250 patients for a variety of aesthetic and reconstructive procedures. The occurrence of capsular contracture was carefully monitored and then analyzed using the Kaplan-Meier method of survival analysis. This method is particularly well suited to analysis of these types of clinical data because it allows for the fact that contractures occur at varying intervals after surgery and that follow-up of patients is incomplete. The probability of capsular contracture with smooth-walled prostheses was found to be significantly greater than with polyurethane-covered implants in each group of patients studied (p less than 0.05). Other complications occurred at a similar rate regardless of prosthesis type. This study supports the belief that polyurethane breast implants have a lower contracture rate; furthermore, it introduces the Kaplan-Meier method for analyzing the outcome of alternative plastic surgical therapies.

The effect of silicone-gel-filled implants on mammography.

Fifty-four women who had previously undergone breast augmentation underwent film-screen mammography using both the standard implant compression technique and, when possible, the implant displacement technique. All had preaugmentation mammography available for evaluation. The area of mammographically visualized breast tissue before and after augmentation mammoplasty was measured using a transparent grid. Patients with subglandular implants had a mean 44% decrease of measurable tissue area with compression mammography and 36% decrease with displacement mammography. Patients with submuscular implants had a mean 25% decrease in measurable tissue area with compression mammography and 15% decrease with displacement mammography. Anterior breast tissue was seen better with displacement mammography, and posterior breast tissue was seen better with compression mammography. Most patients had some degree of parenchymal scarring and lower image quality after augmentation. State-of-the-art mammography was not possible in most patients whose breasts were augmented with silicone-gel-filled implants.

Conservation therapy for breast cancer following augmentation mammaplasty.

Breast conservation therapy (wide local excision, axillary lymph node dissection, and whole-breast irradiation) is an increasingly popular alternative to mastectomy for breast cancer patients. A sizable (and growing) number of breast cancers occur in women with prior augmentation mammaplasty. Augmented breast cancer patients are currently being treated with conservation therapy, but no study has investigated complications and cosmetic results of radiation therapy specifically in this group of women. Between 1981 and 1988, we used conservation therapy in 17 augmented breast cancer patients. Fifteen patients were available for follow-up. In 10 (67 percent), significant capsular contracture occurred in the irradiated breast an average of 12 weeks following completion of treatment. Four patients have undergone revisionary surgery to correct symptoms arising from contracture. This poor outcome contradicts the results reported in previously published studies. We conclude that irradiation of the breast for cancer in augmented women results in a high incidence of scar-tissue contracture and poor cosmetic results.