Effects of Housing System on Dairy Heifer Replacement Cost From Birth to Calving: Evaluating Costs of Confinement, Dry-Lot, and Pasture-Based Systems and Their Impact on Total Rearing Investment.

Replacement heifer rearing is critical for the future of dairy operations, to improve genetic merit and maintain herd size. A myriad of options exist on how to manage, feed, and ultimately raise replacement heifers. Pasture is perceived to offer optimal welfare and an economical housing system for replacement animals, but confinement systems are gaining popularity. This study investigates the costs associated with replacement heifer management decisions from birth to calving, considering the factors of housing systems, labor, feed, and health. The objective of this study was to develop an economic model to determine the cost of raising a replacement heifer managed in confinement, dry-lot, and pasture-based scenarios post-weaning. We accounted for variation in feed, labor, and health inputs and quantified the impact of these individual management decisions. An economic simulation with 10,000 iterations were completed for each situation using @Risk and PrecisionTree add-ons (Palisade Corporation, Ithaca, NY) where health incidence, commodity prices, and management variables were made stochastic. Published literature or sample farm data created parameters used in Pert distributions. Costs and biological responses were reflective of published surveys, literature, and market conditions. Management decision inputs had 3 main factors: housing type, ration composition, and labor utilization. Housing systems were calculated separately for confinement, dry-lot, and pasture scenarios. The mean total cost (min, max) to raise a replacement heifer from birth to calving, assuming the same pre-weaning strategy of group housing with an automatic calf feeder, was found to be $1,919.02 ($1,777.25, $2,100.57), $1,593.57 ($1,490.30, $1,737.26), and $1,335.84 ($1,266.69, $1,423.94) for confinement, dry-lot, and pasture, respectively. Total housing cost per replacement heifer was $423.05, $117.96, and $207.96 for confinement, dry-lot, and pasture management systems, respectively. When compared to total cost, housing contributed 21% for confinement, 7% for dry-lot, and 15% for pasture. Upon analysis of all scenarios, utilizing pasture to raise heifers resulted in a lower overall cost when compared to confinement housing options. Percentage breakdowns of feed, labor, housing, and fixed and variable costs provided more information on efficiency rather than total cost, which makes each situation different in relation to on-farm cost. This cost analysis is critical to assisting farms in making decisions in the utilization of their resources for replacement dairy heifers.

EXTENSION EDUCATION SYMPOSIUM: reinventing extension as a resource--what does the future hold?

The mission of the Cooperative Extension Service, as a component of the land-grant university system, is to disseminate new knowledge and to foster its application and use. Opportunities and challenges facing animal agriculture in the United States have changed dramatically over the past few decades and require the use of new approaches and emerging technologies that are available to extension professionals. Increased federal competitive grant funding for extension, the creation of eXtension, the development of smartphone and related electronic technologies, and the rapidly increasing popularity of social media created new opportunities for extension educators to disseminate knowledge to a variety of audiences and engage these audiences in electronic discussions. Competitive grant funding opportunities for extension efforts to advance animal agriculture became available from the USDA National Institute of Food and Agriculture (NIFA) and have increased dramatically in recent years. The majority of NIFA funding opportunities require extension efforts to be integrated with research, and NIFA encourages the use of eXtension and other cutting-edge approaches to extend research to traditional clientele and nontraditional audiences. A case study is presented to illustrate how research and extension were integrated to improve the adoption of AI by beef producers. Those in agriculture are increasingly resorting to the use of social media venues such as Facebook, YouTube, LinkedIn, and Twitter to access information required to support their enterprises. Use of these various approaches by extension educators requires appreciation of the technology and an understanding of how the target audiences access information available on social media. Technology to deliver information is changing rapidly, and Cooperative Extension Service professionals will need to continuously evaluate digital technology and social media tools to appropriately integrate them into learning and educational opportunities.

The limitation of acute necrosis in retro-patellar cartilage after a severe blunt impact to the in vivo rabbit patello-femoral joint.

We have previously shown that surface lesions and acute necrosis of chondrocytes are produced by severe levels of blunt mechanical load, generating contact pressures greater than 25 MPa, on chondral and osteochondral explants. We have also found surface lesions and chronic degradation of retro-patellar cartilage within 3 years following a 6J impact intensity with an associated average pressure of 25 MPa in the rabbit patello-femoral joint. We now hypothesized that cellular necrosis is produced acutely in the retro-patellar cartilage in this model as a result of a 6J impact and that an early injection of the non-ionic surfactant, poloxamer 188 (P188), would significantly reduce the percentage of necrotic cells in the traumatized cartilage. Eighteen rabbits were equally divided into a 'time zero' group and two other groups carried out for 4 days. One '4 day' group was administered a 1.5 ml injection of P188 into the impacted joint immediately after trauma, while the other was injected with a placebo solution. Impact trauma produced surface lesions on retro-patellar cartilage in all groups. Approximately 15% of retro-patellar chondrocytes suffered acute necrosis in the 'time zero' and '4-day no poloxamer' groups. In contrast, significantly fewer cells (7%) suffered necrosis in the poloxamer group, most markedly in the superficial cartilage layer. The use of P188 surfactant early after severe trauma to articular cartilage may allow sufficient time for damaged cells to heal, which may in turn mitigate the potential for post-traumatic osteoarthritis. Additional studies are needed to improve the efficacy of this surfactant and to determine the long-term health of joint cartilage after P188 intervention.

Health and performance of Holstein calves that suckled or were hand-fed colostrum and were fed one of three physical forms of starter.

Intake of colostrum by neonatal calves and early transition to calf starter are two important factors in successful calf programs. Thirty-one Holstein calves were used to determine health and performance of calves that were 1) allowed to remain with their dams for 3 d and suckle (suckled calves) or were removed from their dams and fed colostrum only by bottle (bottle calves); and were 2) fed ground, pelleted, or textured starters, formulated to be isonitrogenous. Bottle calves were removed from their dams at birth, fed 2.84 L of colostrum, placed in individual hutches, and fed 1.89 L of colostrum 12 h after the first feeding. Suckled calves were removed from their dams after 3 d and placed in individual hutches. Once calves were housed in hutches, they were fed 2 L of whole milk twice daily and were provided starters and water beginning on d 3. Calves were weighed at birth and weekly for 6 wk. Blood samples were obtained at birth, 24 h, and weekly for serum protein determination. Starter intake, fecal scores, and electrolyte treatments were recorded daily. Weaning began when calves had consumed 0.68 kg starter for 2 d consecutively. There were no differences in treatment means between suckled and bottle calves for total gain, grain consumption, days with fecal scores >2, or electrolyte treatments per calf. Average days to weaning was greater for bottle calves compared with suckled calves. Mean serum protein concentration at 24 h was greater for bottle (6.0 g/dl) compared with suckled calves (5.8 g/dl) and only 2 of 15 bottle calves had serum protein concentrations <5.0 g/dl compared with 6 of 16 suckled calves. For starter treatments, calves fed textured starter consumed more total grain, were weaned earlier, and weighed more at 6 wk of age than calves fed pelleted starter. Based on 24-h serum protein concentrations, transfer of passive immunity was greater for bottle calves compared with suckled calves.

Comparison of microbicides for efficacy in protecting mice against vaginal challenge with herpes simplex virus type 2, cytotoxicity, antibacterial properties, and sperm immobilization.

BACKGROUND: Currently, a number of different over-the-counter spermicides and potential microbicides under development are in various phases of clinical trials. It is difficult to know how the various formulations would compare with each other or how efficacious they would be because no existing microbicides are commercially available. GOAL: To evaluate, in a standardized manner, various parameters of potential microbicides. STUDY DESIGN: In an effort to make a comprehensive comparison, several potential microbicides and over-the-counter vaginal products were assayed for their efficacy in protecting mice from infection by herpes simplex virus type 2 (HSV-2), for their cytotoxicity to human vaginal epithelial cells, for their effect on the growth rate of L acidophilus, and for their spermicidal activity. Test formulations were K-Y Plus, Gynol II, Advantage S, Replens, BufferGel, No Fertil, Carrageenan, and PC-550. Additionally, several formulations were evaluated for their use as a possible placebo in microbicide clinical trials. RESULTS: The formulations tested fell into three categories of efficacy in protecting mice from HSV-2 infection. The most efficacious were Carraguard and PC-550. All the other test formulations except methyl cellulose afforded varying degrees of protection against herpes simplex virus-2 infection. It was found that formulations containing the surfactant N9 had a cytotoxic effect on human vaginal cells, inhibited the growth rate of L acidophilus, and exhibited spermicidal activity. In addition, it was found that Replens, BufferGel, No Fertil, and the Carbopol formulation might have some effect on sperm motility. Also, K-Y Jelly significantly inhibited the growth rate of L acidophilus. CONCLUSION: Evaluating formulations under the same testing conditions can help to distinguish among potential formulations that are likely to show promise as safe and effective microbicides.

Nonoxynol-9 causes rapid exfoliation of sheets of rectal epithelium.

Nonoxynol-9 (N-9) containing spermicides and other N-9 containing products are commonly used as lubricants during rectal intercourse. We have previously demonstrated that rectal application of N-9 products in mice can cause exfoliation of epithelial cells, increasing the probability of infection by HSV-2. To determine if N-9-containing products would have a similar effect on the rectal epithelium in humans, the application of K-Y Plus and ForPlay, both over-the-counter (OTC) N-9 products, were compared to the application of two formulations, carrageenan and methyl cellulose, that do not contain N-9. The effects of each formulation were evaluated in 4 human participants. Light and electron microscope examination of rectal lavage specimens collected 15 min post application of N-9 products revealed the presence of sheets of epithelium. Each sheet contained hundreds of epithelial cells that included columnar and goblet cells, varieties of cells typical of rectal epithelial morphology. Sheets of epithelium were not observed in rectal lavage specimens collected 8 to 12 hr post N-9 product use or in either of the timed lavages involving non-N-9 containing formulations. In addition, no sheets of epithelial cells were observed in the baseline lavage specimens. We conclude that the rectal use of N-9-containing products causes a rapid exfoliation of extensive areas of the rectal epithelium. Exfoliation of the epithelium is no longer observed at 8 hr. It is reasonable to assume that the loss of the protective epithelium would render a person more at risk for infection by HIV and other sexually transmitted pathogens. We, therefore, caution against the use of N-9-containing products during rectal intercourse.

A randomized phase II trial comparing two different sequence combinations of autologous vaccine and human recombinant interferon gamma and human recombinant interferon alpha2B therapy in patients with metastatic renal cell carcinoma: clinical outcome and analysis of immunological parameters.

PURPOSE: The clinical observation of spontaneous regression in patients with renal cell carcinoma (RCC) and the response to various immunotherapeutic therapies strongly suggest a role for the host immune system in this disease. Prior studies showed that sequential administration of interferon (IFN) gamma and IFN alpha to RCC patients was safe. Clinical responses as well as immune changes in the peripheral blood mononuclear cell compartment were observed. Autologous tumor cell vaccines (AV) have also demonstrated activity in renal cell carcinoma. We hypothesize that the addition of AV to sequential IFN gamma and a therapy might improve the tumor-specific immune response by providing an appropriate source of antigen in the appropriate cytokine environment. To our knowledge, this is the first trial using AV combined with IFN alpha and IFN gamma. The purpose of this study was to evaluate the feasibility of manufacturing and administering (AV) from resected tumor samples, and administration of AV with combination IFN gamma and IFN alpha therapy. Finally, the impact on immunological parameters of these treatment options was assessed. MATERIALS AND METHODS: Patients with metastatic RCC were randomly assigned to receive AV plus bCG along with a sequential administration of IFN gamma and a either together or after initiation of vaccine. Toxicity and clinical responses were evaluated. Modulations of the immune system were investigated by analyzing phenotype, cytokine mRNA expression, T cell proliferation and cytotoxicity in the peripheral blood mononuclear cell compartment. RESULTS: Fourteen patients with metastatic renal cell carcinoma were enrolled in this study; 9 were available for response evaluation. In a 70 day period, 3 (33%) showed mixed responses, 5 (56%) stable disease and 1 (11%) progression of disease. Toxicities were consistent with previous clinical reports. In the flow-cytometry phenotype analysis, stimulation of distinct subsets of circulating T-lymphocytes and a decrease of CD8+ T cell subsets was demonstrated. T-cell proliferation to allogeneic tumor cell stimulation improved following treatment. IL-4 and IL-5 mRNA levels were reduced in all patients after treatment. Patients who responded to treatment did not produce any IL-4 mRNA at all, before or after treatment. CONCLUSIONS: AV with IFNgamma and IFNalpha therapy might induce a MHC class-mediated cytotoxic T lymphocyte (CTL) response. We suggest that adequate therapy might direct T cell response toward a Th1 type response. We hypothesize a state of improved immune readiness in patients who might eventually respond to immunotherapy.

Health status, staffing, and medicaid reimbursement in nursing homes: 1985 to 1995.

CONTEXT: Policy changes implemented by Medicaid and Medicare in the early 1980s resulted in a functionally more dependent nursing home population. OBJECTIVES: This paper contends that (1) staffing in nursing homes has become more efficient; (2) nursing home residents are functionally more dependent;(3) Medicaid per diem reimbursement is inadequate. DATA SOURCES: Staffing data came from the National Nursing Home Facility Survey conducted by the National Center for Health Statistics (NCHS) in 1985 and 1995. Functional dependency data, defined as assistance with any of six Activities of Daily Living (ADLs), came from the NCHS National Nursing Home Current Resident Surveys in 1985 and 1995. Reimbursement rates came from the State Medicaid Reimbursement Surveys conducted by the University of California at San Francisco to which the Consumer Price Index, Hospital and Related Services Item was applied. DATA SYNTHESIS: Administration decreased by 4.4 full-time equivalents (FTEs) (80.0%) per 100 beds, whereas patient care increased by 8.2 FTEs (18.9%). Residents requiring assistance with four or more ADLs increased by 9.9%, and the mean number of ADLs per patient increased from 3.9 to 4.3. Applying the Consumer Price Index to the 1984 reimbursement rate indicated an annual deficit of 5526.00 dollars for each Medicaid patient by 1995. CONCLUSIONS: This research strongly supports its contentions but fails to demonstrate them conclusively. The data indicate that long-term care facilities have reallocated staffing to accommodate the requirements of more functionally dependent residents and that Medicaid reimbursement has failed to maintain its initial purchasing power.

Evaluation of a probe for predicting beef tenderness.

A series of three experiments were conducted to evaluate the performance of the MIRINZ (Meat Industry Research Institute of New Zealand) tenderness probe. In the first experiment, assessments on raw samples from two different muscles (longissimus lumborum and semimembranosus) were obtained using the tension head. Results indicated D50 values (torque at 50° of rotation) were the most highly related to both sensory (taste, olfactory, and feeling factors measured by a trained sensory panel) and consumer (hedonic ratings provided by untrained consumers) properties and were the values of choice, since all probe values were essentially measuring the same characteristics. In the second experiment, assessments were made using both the tension and shear heads on raw and cooked striploin (longissimus lumborum) steaks. Results confirmed probe values were essentially measuring the same characteristics, but indicated raw tension head, area 2 values (area before 50° of rotation) were more highly related to both sensory and consumer properties than were D50 values. However, probe values from raw samples did not account for a sufficient amount of variation in either sensory or consumer properties to be useful predictors of these traits, and stepwise, linear regression did not improve the predictive value of raw probe values, since all probe values were interrelated. Probe values on cooked samples indicated the shear head and area 3 values (area under the entire trace) were the most related to both sensory and consumer properties and were the values of choice. Based upon the amount of variation accounted for in sensory and consumer traits, probe area 3 values using the shear head on cooked samples provided greater predictive value for both sensory and consumer traits than Warner-Bratzler shear values obtained from steaks cooked either fresh or after being frozen and thawed. In experiment 3, correlations with individual, parametric character notes from the texture profiles of two different muscles provided no clear indication as to the textural properties being assessed by the probe. However, the MIRINZ probe appears to be a quick viable alternative to the Warner-Bratzler shear for providing an objective measure of cooked meat tenderness.

School problems and the family physician.

Children with school problems pose a challenge for the family physician. A multidisciplinary team of professionals can most appropriately assess and manage complex learning problems, which are often the cause of poor school performance. The family physician's primary role in this process is to identify or exclude medical causes of learning difficulties. An understanding of the complicated nature of school problems, the methods used to assess, diagnose and treat them, and the resources available to support the child and family are essential to successful management. Various references and resources are helpful for a more in-depth study of specific school problems.

An investigation of the latency period between sperm oolemmal adhesion and oocyte penetration.

In clinical studies of the ability of capacitated human sperm to penetrate zona-free hamster eggs, we have previously observed that the ratio of oolemmal adherent to penetrating sperm varied between men. Sperm incorporation did not occur immediately following gamete adhesion and not all adherent sperm penetrated the egg. To further investigate this phenomenon, comparisons were made of the kinetics of gamete adhesion, membrane fusion, and sperm incorporation of capacitated mouse and human spermatozoa by zona-free hamster eggs and of mouse sperm by zona-free mouse and hamster eggs. Eggs were inseminated with either capacitated human or mouse sperm or combinations of both, washed out of sperm suspension after initial gamete adherence, and further incubated in sperm-free medium. Gamete membrane fusion was judged by dye transfer of Hoechst 33342 and sperm entry of the cortical ooplasm by observation of expanded sperm heads within acridine orange stained eggs. Oolemmal adherent mouse and human sperm fused with and penetrated zona-free hamster eggs at different times whether eggs were inseminated in parallel or with combinations of sperm of both species. Oolemmal adherent mouse sperm penetrated zona-free hamster eggs prior to their penetration of zona-free mouse eggs. Ultrastructural studies of zona-free human eggs inseminated with human sperm confirmed prior observations with hamster eggs that only acrosome-reacted human sperm adhere to the oolemma. These results have lead us to postulate that sperm entry into the egg may occur through a "zipper" mechanism involving the ligation of local gamete receptors similar to the incorporation of target particles by phagocytes and suggest that not all oolemmal adherent human sperm are capable of being incorporated although they have undergone an acrosome reaction.

Pushing the frontiers of science--the Population Council's Microbicide Basic Science Network on vaginal microbicide research.

Microbicides are the new frontier of products for the prevention of sexually transmitted infections (STIs). Twelve years ago, scientists realized that existing spermicides had some anti-microbial activity and perhaps could be improved or reformulated with new compounds to provide a complete barrier against STIs. However, the development and successful marketing of an effective, non-toxic, convenient and affordable vaginal microbicide that women can use on a long-term basis hinges on a close collaboration between research institutions and the pharmaceutical industry. The Population Council has recently taken the first step in instituting a multifaceted strategy for the development of a microbicide by establishing the Microbicide Basic Science Network, comprising of scientists with diverse backgrounds and expertize.

Phenylephrine, endothelin, prostaglandin F2alpha' and leukemia inhibitory factor induce different cardiac hypertrophy phenotypes in vitro.

In these studies, we show that endothelin (ET), leukemia inhibitory factor (LIF), phenylephrine (PE), and prostaglandin F2alpha (PGF2alpha), which are all hypertrophic for neonatal rat cardiac myocytes in culture, induce distinct morphological, physiological, and genetic changes after a 48-h treatment. Transmission electron microscopy revealed differences in myofibril organization, with ET-treated cells containing the most mature-looking myofibrils and PGF2alpha- and LIF-treated cells the least. ET- and PE-treated cultures contained the same number of beating cells as control, but LIF and PGF2alpha treatment increased the number of beating cells 180%. Treatment with LIF, PE, and PGF2alpha increased the beat rate to 3.3 times that of control. After exposure to the beta-adrenergic agonist isoproterenol, the beat rate increased 50% for PGF2alpha' 54% for PE, 84% for LIF, and 125% for control. ET treatment did not increase the beat rate, nor did these cells respond to isoproterenol. ET, LIF, and PE increased the production of atrial natriuretic peptide (ANP) by three-fold and PGF2alpha by 18-fold over nontreated cells. Brain natriuretic peptide (BNP) was increased fourfold by ET and PE, 16-fold by LIF, and 29-fold by PGF2alpha. Interestingly, on a pmol/L basis, only LIF induced more BNP than ANP. Treatment with all agents led to a similar pattern of gene induction: increased expression of the embryonic genes for ANP and skeletal alpha-actin, and less than a twofold change in the constitutively expressed gene myosin light chain-2, with the exception that LIF did not induce skeletal alpha-actin. Each agent, however, induced ANP mRNA with a different time-course. We conclude that at least four distinct cardiac myocyte hypertrophy response programs can be induced in vitro. Further studies are necessary to determine whether these correlate to the different types of cardiac hypertrophy seen in vivo.

Carrageenan-based nonoxynol-9 spermicides for prevention of sexually transmitted infections.

BACKGROUND AND OBJECTIVES: Carrageenan-based nonoxynol-9 (N-9)-containing formulations were developed in response to the concern that over the counter (OTC) spermicides may not protect people from HIV infection and other sexually transmitted pathogens. GOAL OF THIS STUDY: The goal of this study was to compare the efficacy of carrageenan-based formulations to OTC spermicides in protecting mice from infection by herpes simplex virus 2 (HSV-2). STUDY DESIGN: Mice were challenged with vaginal inoculation of HSV-2 after pretreatment with test formulations. RESULTS: Carrageenan-based formulations were significantly more effective than currently marketed spermicides containing the same amount of N-9. Efficacy was demonstrated over a wide pH range. The carrageenan-based formulations could be autoclaved without losing antiviral activity and remained active in the vagina for several hours. CONCLUSIONS: We conclude that carrageenan-based N-9 formulations are likely to provide a more significant degree of protection against HSV-2 and other enveloped viruses than current OTC spermicides while providing comparable spermicidal activity.

Breast cancer in older women.

The American Geriatric Society currently recommends screening mammography for women up to 85 years of age whose life expectancy is three years or longer. The value of clinical breast examinations in older women needs further study. Total mastectomy and partial mastectomy with postoperative radiation therapy yield similar results in localized breast cancer. Postoperative irradiation may be avoided in women with small tumors (2.5 cm or less in diameter) who have undergone quadrantectomy. Lymph node dissection is important for tumor staging but significantly increases the risks and morbidity of surgery. Lymph node mapping may obviate the need for lymphadenectomy in many older women. Adjuvant hormonal therapy for at least two years appears to be beneficial in all women with hormone-receptor-rich tumors. Adjuvant chemotherapy is indicated in women with lymph node involvement or high-risk tumors with no lymph node involvement. Unless life-threatening metastases are present, hormonal therapy is the first approach to metastatic cancer. Chemotherapy is indicated if endocrine therapy is unsuccessful or life-threatening metastases are present. Most chemotherapy regimens appear to be well tolerated, even by women over 70 years of age. Special treatment should be employed for metastases to tumor sanctuaries (i.e., brain, eyes), the long bones, the spine and the chest wall.

Ultrastructure of the murine cervix following infection with Chlamydia trachomatis.

We have used electron microscopy to follow the course of Chlamydia trachomatis infection in the mouse cervix. Although numerous elementary bodies (EBs) were observed on the surface of epithelial cells, evidence of coated pits or entry of EBs into epithelial cells were rarely observed. After 2 days postinoculation, inclusions contained numerous reticulate bodies (RBs) and a few intermediate forms (IBs). At 4 days postinoculation, microvilli were no longer present on infected cells and inclusions had often ruptured and released chlamydiae into the cytoplasm of the cells. Aberrant and miniature RBs, similar to those which have been described in in vitro models for persistence, were observed. Unlike the case in vitro where inclusion cause rupture of the cell, infection in vivo may result in rupture of inclusions within the cytoplasm of infected cells. Our observations also suggest that persistent chlamydia can form in some of the cells of the cervical epithelium that are infected by the initial inoculation.

Structure-based design of peptides that recognize the CD4 binding domain of HIV-1 gp120.

DESIGN: Envelope protein-specific antiviral peptides, called mucibodies, that can specifically recognize and bind to the surface unit protein gp120 of HIV-1 were designed. The initial mucibody binding target was the V3 loop of HIV-1 gp120. Here, the gp120-CD4 binding domain was chosen as the site of mucibody binding. The CD4 binding domain of gp120 is known to be a conformational epitope and is involved in the earliest events of viral entry into many cells. METHODS: The design of the mucibody antivirals was based on previous observations that antibody complementarity determining regions (CDR) are generally similar to the repeating loops or knob structures found in the 20-residue tandem repeat domain of human mucin MUC1. The heavy chain CDR3 from the bacteriophage display antibody b12 was used to construct two mucibodies, b12-CDR1 and b12-26. RESULTS: Peptides corresponding to three tandem repeats were shown to bind directly to the CD4 binding domain of HIV-1 gp120 in a solid-phase enzyme-linked immunosorbent assay. These mucibody peptides also disrupted the gp120-CD4 interaction in a solution-phase inhibition assay. Finally, mucibodies neutralized primary and laboratory macrophage-tropic isolates of HIV-1. CONCLUSIONS: There is a potential for medical use of these peptides as topical vaginal microbicides in preventing HIV-1 transmission during sexual contact. These results also suggest that multivalent, non-immunogenic binding proteins of virtually any specificity could be constructed for use in therapeutic applications involving infectious diseases and immune system dysfunction.