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1.
Phys Rev Lett ; 130(18): 183602, 2023 May 05.
Article in English | MEDLINE | ID: mdl-37204878

ABSTRACT

The Heisenberg limit to laser coherence C-the number of photons in the maximally populated mode of the laser beam-is the fourth power of the number of excitations inside the laser. We generalize the previous proof of this upper bound scaling by dropping the requirement that the beam photon statistics be Poissonian (i.e., Mandel's Q=0). We then show that the relation between C and sub-Poissonianity (Q<0) is win-win, not a tradeoff. For both regular (non-Markovian) pumping with semiunitary gain (which allows Q→-1), and random (Markovian) pumping with optimized gain, C is maximized when Q is minimized.

3.
Org Lett ; 2(19): 2967-70, 2000 Sep 21.
Article in English | MEDLINE | ID: mdl-10986084
4.
Plast Reconstr Surg ; 105(7): 2500-12; discussion 2513-4, 2000 Jun.
Article in English | MEDLINE | ID: mdl-10845308

ABSTRACT

Less than 1 percent of the women interested in having larger breasts elect to have surgical augmentation mammaplasty with insertion of breast implants. The purpose of this report is to describe and test the efficacy of a nonsurgical method for breast enlargement that is based on the ability of tissues to grow when subjected to controlled distractive mechanical forces. Seventeen healthy women (aged 18 to 40 years) who were motivated to achieve breast enlargement were enrolled in a single-group study. The participants were asked to wear a brassiere-like system that applies a 20-mmHg vacuum distraction force to each breast for 10 to 12 hours/day over a 10-week period. Breast size was measured by three separate methods at regular intervals during and after treatment. Breast tissue water density and architecture were visualized before and after treatment by magnetic resonance imaging scans obtained in the same phase of the menstrual cycle. Twelve subjects completed the study; five withdrawals occurred due to protocol noncompliance. Breast size increased in all women over the 10-week treatment course and peaked at week 10 (final treatment); the average increase per woman was 98 +/- 67 percent over starting size. Partial recoil was seen in the first week after terminating treatment, with no significant further size reduction after up to 30 weeks of follow-up. The stable long-term increase in breast size was 55 percent (range, 15 to 115 percent). Magnetic resonance images showed no edema and confirmed the proportionate enlargement of both adipose and fibroglandular tissue components. A statistically significant decrease in body weight occurred during the course of the study, and scores on the self-esteem questionnaire improved significantly. All participants were very pleased with the outcome and reported that the device was comfortable to wear. No adverse events were recorded during the use of the device or after treatment. We conclude that true breast enlargement can be achieved with the daily use of an appropriately designed external expansion system. This nonsurgical and noninvasive alternative for breast enlargement is effective and well tolerated.


Subject(s)
Breast/abnormalities , Tissue Expansion/instrumentation , Tissue Expansion/methods , Adult , Female , Humans , Pressure , Treatment Outcome , Vacuum
5.
Otolaryngol Head Neck Surg ; 122(3): 346-8, 2000 Mar.
Article in English | MEDLINE | ID: mdl-10699807

ABSTRACT

OBJECTIVES: Ventilation tubes are the mainstay of surgical treatment for eustachian tube dysfunction and have been used successfully for many years. Certain disadvantages of ventilation tubes, however, have prompted research into alternative techniques including laser myringotomy. We investigated the use of KTP laser myringotomy in conjunction with topical mitomycin C to delay healing and prolong the patency of the myringotomy. METHODS: Twenty myringotomies were created in 10 Sprague-Dawley rats. A solution of mitomycin C was applied to the intact tympanic membrane for 15 minutes. The solution was then suctioned free, and a myringotomy was created with a KTP laser. Fifty-three rats with saline application serving as controls from a previous study were used to allow statistical assessment. RESULTS: The myringotomies remained open for a median of 9.5 weeks. Control myringotomies, which received saline solution instead of mitomycin C, healed within a median of 1.5 weeks. The difference was statistically significant at P < 0.0001. No complications were noted. CONCLUSION: Topically administered mitomycin C before laser myringotomy is effective in prolonging the patency of laser myringotomies in rats. The patency rate is similar to that achieved in experiments in which topical mitomycin C is placed into the myringotomy site created by the laser.


Subject(s)
Laser Therapy , Middle Ear Ventilation , Mitomycin/pharmacology , Nucleic Acid Synthesis Inhibitors/pharmacology , Premedication , Wound Healing/drug effects , Administration, Topical , Animals , Postoperative Complications/etiology , Postoperative Complications/prevention & control , Rats , Rats, Sprague-Dawley
6.
Plast Reconstr Surg ; 105(1): 290-301, 2000 Jan.
Article in English | MEDLINE | ID: mdl-10627000

ABSTRACT

As we have gained experience with the extended superficial musculoaponeurotic system (SMAS) technique in face lifting, refinements in our procedure have led to increased consistency in results. The important factors that have led to our technical modifications include the following: (1) the significance of the retaining ligaments of the midface, which determine the degree of surgical dissection required for both skin and SMAS in rhytidectomy; (2) the changes in facial shape that occur with aging, secondary to the descent of facial fat; (3) the possibility of modifying facial shape through the repositioning of facial fat in an extended SMAS face lift; (4) the improved longevity of result to be obtained by incorporating Vicryl mesh into SMAS fixation; (5) the artistic nuances of incision design that help to minimize scar perceptibility. Understanding these factors enables surgeons to use the extended SMAS technique successfully with more challenging cases, enhancing facial appearance while minimizing signs that the patient has undergone a surgical procedure.


Subject(s)
Polyglactin 910 , Rhytidoplasty/methods , Surgical Mesh , Adult , Aged , Esthetics , Female , Follow-Up Studies , Humans , Male , Middle Aged , Suture Techniques , Treatment Outcome
7.
J Org Chem ; 65(26): 9054-8, 2000 Dec 29.
Article in English | MEDLINE | ID: mdl-11149851

ABSTRACT

The new guanidinylation reagent N,N'-diBoc-N''-triflylguanidine was used to efficiently convert multiamine-containing glycosides including kanamycin A and B, tobramycin, paromomycin, and neomycin B to the corresponding fully guanidinylated analogues (guanidinoglycosides). This transformation occurs in the presence of H(2)O under mild conditions. Guanidinotobramycin and guanidinoneomycin B were found to inhibit the replication of the HIV virus with activities approximately 100 times greater than the parent aminoglycosides.


Subject(s)
Anti-HIV Agents/chemical synthesis , Glycosides/chemical synthesis , Guanidines/chemical synthesis , Anti-HIV Agents/pharmacology , Carbohydrate Sequence , HeLa Cells , Humans , Indicators and Reagents , Molecular Sequence Data
8.
J Biol Chem ; 274(31): 21878-84, 1999 Jul 30.
Article in English | MEDLINE | ID: mdl-10419507

ABSTRACT

The absence of viral receptors is a major barrier to efficient gene transfer in many cells. To overcome this barrier, we developed an artificial receptor based on expression of a novel sugar. We fed cells an unnatural monosaccharide, a modified mannosamine that replaced the acetyl group with a levulinate group (ManLev). ManLev was metabolized and incorporated into cell-surface glycoconjugates. The synthetic sugar decorated the cell surface with a unique ketone group that served as a foundation on which we built an adenovirus receptor by covalently binding biotin hydrazide to the ketone. The artificial receptor enhanced adenoviral vector binding and gene transfer to cells that are relatively resistant to adenovirus infection. These data are the first to suggest the feasibility of a strategy that improves the efficiency of gene transfer by using the biosynthetic machinery of the cell to engineer novel sugars on the cell surface.


Subject(s)
Adenoviridae , Endothelium, Vascular/physiology , Gene Transfer Techniques , Genetic Vectors , Hexosamines/pharmacokinetics , Receptors, Cell Surface/physiology , Transfection/methods , beta-Galactosidase/genetics , 3T3 Cells , Animals , Biotin/analogs & derivatives , Biotin/pharmacokinetics , Cells, Cultured , Endothelium, Vascular/cytology , Genes, Reporter , Humans , Kinetics , Mice , Models, Biological , Receptors, Cell Surface/biosynthesis , Streptavidin/pharmacokinetics , Umbilical Veins , beta-Galactosidase/biosynthesis
10.
Plast Reconstr Surg ; 100(2): 502-8, 1997 Aug.
Article in English | MEDLINE | ID: mdl-9252622
11.
Plast Reconstr Surg ; 99(7): 2036-50; discussion 2051-5, 1997 Jun.
Article in English | MEDLINE | ID: mdl-9180729

ABSTRACT

To delineate the histologic effects of laser resurfacing at photoaged skin, a protocol was designed to biopsy laser test sites in conjunction with adjacent actinically damaged skin at the time of rhytidectomy. Five patients with photodamaged skin underwent resurfacing of the preauricular region to examine the effect of increasing pulse energy and increasing number of passes on depth of dermal penetration. Histologic examination of these specimens showed that the depth of laser injury was dose-dependent. Increasing pulse energy created a deeper wound, and increasing the number of passes similarly produced a larger band of necrosis. Ten patients with photodamaged skin underwent resurfacing of the preauricular region 15 days to 6 months prior to undergoing a rhytidectomy. A comparison of the laser-resurfaced test spot with the adjacent untreated photodamaged skin demonstrated consistent histologic changes to both epidermis and dermis in all specimens examined. Following laser resurfacing, epidermal atrophy and atypia were eliminated, and all specimens exhibited a regeneration of epithelium that was normal in its morphology. Melanocytic hypertrophy and hyperplasia were corrected following treatment, although density and function of epidermal melanocytes appeared normal. All specimens exhibited a substantial amount of neocollagen formation involving both the superficial and middermis following resurfacing. In association with new collagen development within the dermis, there was noted to be a similar degree of proliferation of elastic fibers, as well as a diminution of glycosaminoglycans, which are typically present in actinically damaged elastotic dermis. To determine the effect of laser resurfacing on-black skin, laser test spots were placed in the postauricular region of three black patients. Biopsy of these test sites showed that the histologic effects of laser resurfacing were similar to those observed in Caucasian patients, with complete repopulation of epidermal melanocytes in specimens biopsied 3 months following resurfacing. The histologic effects of laser resurfacing are microscopically similar to those of phenol peeling in terms of the amelioration of photodamage. The distinction between these two treatment methods lies in their apparent effect on epidermal melanocytes, which appear to function normally following laser resurfacing.


Subject(s)
Laser Therapy , Rhytidoplasty , Skin Aging/pathology , Atrophy , Biopsy , Black People , Carbon Dioxide , Cell Count , Cell Division , Chemexfoliation , Collagen/analysis , Dermatologic Agents/therapeutic use , Elastic Tissue/pathology , Epidermis/pathology , Epithelium/pathology , Face , Follow-Up Studies , Glycosaminoglycans/analysis , Humans , Hyperplasia , Hypertrophy , Laser Therapy/methods , Melanocytes/pathology , Necrosis , Phenols/therapeutic use , Regeneration , Skin/pathology , Skin Pigmentation , White People
12.
J Immunol ; 157(4): 1758-72, 1996 Aug 15.
Article in English | MEDLINE | ID: mdl-8759766

ABSTRACT

We have used fas-defective MRL-lpr/lpr mice to study the effects of the staphylococcal enterotoxin superantigens on the development of autoimmune, inflammatory joint disease in animals that are susceptible to the development of rheumatoid arthritis-like disease. We show that systematic administration by a single i.p. injection of staphylococcal enterotoxin B (SEB; 10 micrograms/mouse) caused a mild, inflammatory arthritis +30 days postchallenge in the knee joints of young (< 2-mo-old) MRL-lpr/lpr mice, but not aged-matched MRL +/+ mice. In aged (> 8-mo-old) MRL-lpr/lpr mice, but not in aged MRL +/+ mice, SEB caused a severe, inflammatory arthritis, as assessed histologically, and systemic autoimmune disease, including glomerulonephritis and autoantibody production. Furthermore, in aged MRL-lpr/lpr mice, SEB but not heat-denatured SEB caused acute weight loss and elevated levels of serum proinflammatory cytokines. Compared with highly purified peritoneal macrophages obtained from either aged MRL +/+, young MRL-lpr/lpr, or young MRL +/+, peritoneal macrophages obtained from aged MRL-lpr/lpr mice constitutively expressed 2- to 10-fold greater levels of TNF-alpha, IL-1 beta, IL-6, and IL-10, and produced elevated amounts of these cytokines when treated in vitro with SEB. SEB-challenged aged MRL-lpr/lpr mice treated with anti-TNF mAb (100 micrograms/mouse; every other day), anti-V beta 8 TCR mAb (250 micrograms/mouse; every other day), or orally with the novel TNF-alpha inhibitor MDL 201,449A (9-[(1R, 3R)-trans-cyclopentan-3-ol] adenine; 25 mg/kg/day) exhibited reduced inflammatory arthritis, autoantibody formation, and serum TNF-alpha levels, but not IL-10 levels, after +30 days of treatment. These data suggest that SEB is an extremely potent macrophage-activating factor in vitro and in vivo, enhancing several aspects of autoimmune disease in MRL-lpr/lpr mice, and that anti-TNF therapies may have potential use in inflammatory arthritis.


Subject(s)
Antibodies, Monoclonal/therapeutic use , Antigens, Bacterial/immunology , Arthritis, Infectious/prevention & control , Autoimmune Diseases/immunology , Cytokines/biosynthesis , Enterotoxins/immunology , Glomerulonephritis/immunology , Receptors, Antigen, T-Cell, alpha-beta/immunology , Superantigens/immunology , Tumor Necrosis Factor-alpha/antagonists & inhibitors , Tumor Necrosis Factor-alpha/immunology , fas Receptor/physiology , Aging/immunology , Animals , Antibodies, Monoclonal/immunology , Antibodies, Monoclonal/pharmacology , Arthritis, Infectious/immunology , Autoimmune Diseases/complications , Cells, Cultured , Cytokines/genetics , Glomerulonephritis/complications , Histocompatibility Antigens Class II/immunology , Macrophages, Peritoneal/immunology , Macrophages, Peritoneal/metabolism , Mice , Mice, Mutant Strains , Protein Denaturation , Receptors, Antigen, T-Cell, alpha-beta/physiology , Transcription, Genetic/drug effects , Tumor Necrosis Factor-alpha/genetics , Tumor Necrosis Factor-alpha/physiology , fas Receptor/genetics
13.
Nurse Pract ; 21(2): 26, 29-32, 42, 1996 Feb.
Article in English | MEDLINE | ID: mdl-8907782

ABSTRACT

The purpose of this cross-sectional descriptive study was to explore factors that influence the timing of the first prenatal care visit of pregnant adolescents. Although researchers agree that barriers to prenatal care need to be identified and interventions formulated, barriers have not been well defined for any specific population. Increased availability and adequacy of health care resources, more family system support, and higher self-care agency scores are hypothesized to predict earlier prenatal care. A convenience sample of 51 pregnant adolescents from a university clinic was surveyed. The study found that the availability/adequacy of health care resources was the most significant predictor of the initiation of prenatal care (p = .03). Of the various health care resources assessed, only the ease in attaining a medical card was positively related to the onset of prenatal care. Practitioners can be instrumental in disseminating information about the availability of health care resources and in easing access to those resources through local and national political involvement.


PIP: In order to identify the factors that influence the gestational age when pregnant adolescents seek prenatal care, data were gathered from a convenience sample of 51 pregnant adolescents who were younger than 18, nullipara, received a government-sponsored medical card, and could read at the sixth-grade level or higher. Availability and adequacy of resources and the family support system were assessed using a modified version of Slusher's conditioning factor data collection tool, and self-care agency was measured using the Denyes Self-Care Agency Instrument. Sociodemographic data were also collected, and gestational age at initial prenatal screening was based on calculations of the estimated date of delivery. In the analysis of structural and nonstructural barriers to initiation of prenatal care, the only significance found was associated with the structural barriers of availability and adequacy of health care resources (the ease of attaining a medical card). The perceived difficulty of dealing with the medical-card system, rather than actual unavailability of funding, created the barrier to seeking care. There was no support for the hypotheses that increased family support or higher self-care agency would be associated with earlier onset of care. An interesting, but not statistically significant, association showed that the subsample with the lowest reported family support and health care resources (the Black adolescents) had the highest self-care scores and earliest prenatal care initiation. It is concluded that additional research is needed on the actual and perceived barriers to prenatal care faced by adolescents and that health care providers can play a role in improving the current Medicaid system.


Subject(s)
Health Services Accessibility , Patient Acceptance of Health Care , Pregnancy in Adolescence , Prenatal Care , Adolescent , Female , Humans , Nursing Theory , Parity , Predictive Value of Tests , Pregnancy , Self Care , Surveys and Questionnaires , Time Factors
14.
Clin Plast Surg ; 23(1): 3-16, 1996 Jan.
Article in English | MEDLINE | ID: mdl-8617029

ABSTRACT

This article describes new trends, techniques, and instrumentation in aesthetic surgery. Advances in our understanding of anatomy and the changes that come about with intrinsic and extrinsic factors are discussed. Specifically, anatomic approaches to rhytidectomy, the preservation of lid shape in blepharoplasty, and CO2 facial resurfacing are highlighted. Body contouring surgical techniques, including minimal scar breast reductions, endoscopic-assisted augmentation mammoplasty, and superficial liposuction, are reviewed.


Subject(s)
Surgery, Plastic/trends , Antihypertensive Agents/therapeutic use , Clonidine/therapeutic use , Esthetics , Eyelids/surgery , Female , Humans , Laser Therapy , Lipectomy , Male , Mammaplasty , Preoperative Care , Rhytidoplasty , Surgery, Plastic/methods , Surgical Flaps
15.
J Immunol ; 155(10): 4829-37, 1995 Nov 15.
Article in English | MEDLINE | ID: mdl-7594485

ABSTRACT

MRL-lpr/lpr mice are defective in the fas Ag/APO-1 apoptosis gene (CD95). Using the hepatotoxin D-galactosamine (D-GalNH2), we demonstrate that MRL-lpr/lpr mice have an increased susceptibility to staphylococcal enterotoxin B (SEB)-induced lethal shock, which causes them to exhibit the septic shock-like behaviors of fur ruffling and listlessness, and death occurs within 8 to 18 h. SEB susceptibility is greater in V beta 8.2 TCR transgenic MRL-lpr/lpr mice than in nontransgenic mice. In studies designed to elucidate the molecular pathways of SEB-induced septic shock, we found that C57Bl/6.Ab0/Ab0, MHC class II-deficient "C2D" mice, but not C57Bl/6-(+/+) mice, are nonresponsive to challenge with SEB. C2D mice, backcrossed with the fas mutation resulting in double-knockout C2D;lpr/lpr mice, are more susceptible to challenge with SEB/D-GalNH2. The LD50s for C57Bl/6.C3H-gld/gld "fas ligand-mutant mice" challenged with SEB/D-GalNH2 were comparable to C57Bl/6.MRL-lpr/lpr and MRL-lpr/lpr mice, suggesting that reciprocal mutations in either fas or fas ligand increases susceptibility to bacterial superantigens (SAGs). SEB-induced lethal shock can be reversed by treatment with Abs to V beta 8 TCR, MHC class II Ia+, IL-2, and TNF-alpha, by the immunosuppressant cyclosporin A, or by treatment with carbocyclic nucleoside analogues. These data indicate that SAG-induced septic shock is dependent on interactions with the TCR and MHC class II Ags, and they also suggest a critical role for a functional fas and/or fas ligand in resistance to SAG-induced septic shock.


Subject(s)
Enterotoxins/immunology , Histocompatibility Antigens Class II/immunology , Receptors, Antigen, T-Cell/immunology , Shock, Septic/immunology , Staphylococcus , T-Lymphocytes/immunology , fas Receptor/genetics , Animals , Histocompatibility Antigens Class II/genetics , Mice , Mice, Knockout , Mice, Mutant Strains , Mice, Transgenic , Mutation , Receptors, Antigen, T-Cell/genetics , Superantigens/immunology , fas Receptor/immunology
16.
Clin Plast Surg ; 22(2): 295-311, 1995 Apr.
Article in English | MEDLINE | ID: mdl-7634739

ABSTRACT

The objective in rhytidectomy is to rejuvenate and improve facial appearance. To obtain consistent results, facelifting should be approached not just as a tightening or lifting procedure but also as a reconstructive procedure, reversing the anatomic changes that occur in aging. The ability to bring aesthetic harmony back into the aging face requires the blending of surgical technique, anatomic knowledge, and artistic sensitivity to individualize the surgical approach for a given patient. To obtain surgical rejuvenation while minimizing signs of surgical distortion remains the ultimate goal of our facelifting procedures.


Subject(s)
Rhytidoplasty/methods , Female , Humans , Postoperative Complications
18.
Clin Nurse Spec ; 8(1): 2-5, 1994 Jan.
Article in English | MEDLINE | ID: mdl-8299060

ABSTRACT

The image of nurse-midwifery forms a barrier to utilization that is just as, if not more, formidable as laws restricting practice. In this paper, the issue of image for its impact on the practice of nurse-midwifery is analyzed. Historical, technological, consumer-oriented, and nursing-oriented factors that have affected midwifery's image and the profession's current status are explored. Recommendations to clarify the role and image, including political involvement, networking strategies, and research, are discussed. Although nurse-midwives, who emphasize cost-effective, quality, primary care, should be in the forefront of health care delivery, they are still widely misperceived, underutilized, and unrecognized as mainstream health care providers. In this era of health care reform, it is essential that the role and image of the nurse-midwife be clearly defined to the general public, maternity care consumer, fellow health care providers, and legislators.


Subject(s)
Nurse Midwives , Professional Practice , Social Perception , Health Policy , Humans , Interprofessional Relations , Role
19.
Clin Plast Surg ; 20(1): 9-25, 1993 Jan.
Article in English | MEDLINE | ID: mdl-8420712

ABSTRACT

A complete armamentarium using phenol, trichloroacetic acid, and dermabrasion allows the physician to successfully treat a variety of difficult photoaged skin problems in a consistent fashion. These three techniques have their specific indications, and patient selection is the key to a successful outcome. Proper attention to technical detail will allow the physician to fine-tune technique to meet the individual's needs. It is important to realize that phenol, trichloroacetic acid, and dermabrasion are not exclusive of each other, but are additive in their value. As one becomes well versed in these differing treatment modalities, one can tailor these techniques to obtain consistent results according to the needs and desires of the patient.


Subject(s)
Chemexfoliation/methods , Dermabrasion/methods , Phenols/therapeutic use , Skin Aging , Trichloroacetic Acid/therapeutic use , Chemexfoliation/standards , Dermabrasion/adverse effects , Dermabrasion/standards , Humans , Occlusive Dressings , Phenol , Phenols/administration & dosage , Phenols/adverse effects , Postoperative Care , Preoperative Care , Recurrence , Skin Aging/drug effects , Skin Aging/pathology , Trichloroacetic Acid/administration & dosage , Trichloroacetic Acid/adverse effects
20.
Plast Reconstr Surg ; 89(3): 441-9; discussion 450-1, 1992 Mar.
Article in English | MEDLINE | ID: mdl-1741467

ABSTRACT

Controversy persists regarding the relationship of the superficial facial fascia (SMAS) to the mimetic muscles, deep facial fascia, and underlying facial nerve branches. Using fresh cadaver dissection, and supplemented by several hundred intraoperative dissections, we studied facial soft-tissue anatomy. The facial soft-tissue architecture can be described as being arranged in a series of concentric layers: skin, subcutaneous fat, superficial fascia, mimetic muscle, deep facial fascia (parotidomasseteric fascia), and the plane containing the facial nerve, parotid duct, and buccal fat pad. The anatomic relationships existing within the facial soft-tissue layers are (1) the superficial facial fascia invests the superficially situated mimetic muscles (platysma, orbicularis oculi, and zygomaticus major and minor); (2) the deep facial fascia represents a continuation of the deep cervical fascia cephalad into the face, the importance of which lies in the fact that the facial nerve branches within the cheek lie deep to this deep fascial layer; and (3) two types of relationships exist between the superficial and deep facial fascias: In some regions of the face, these fascial planes are separated by an areolar plane, and in other regions of the face, the superficial and deep fascia are intimately adherent to one another through a series of dense fibrous attachments. The layers of the facial soft tissue are supported in normal anatomic position by a series of retaining ligaments that run from deep, fixed facial structures to the overlying dermis. Two types of retaining ligaments are noted as defined by their origin, either from bone or from other fixed structures within the face.(ABSTRACT TRUNCATED AT 250 WORDS)


Subject(s)
Aging/pathology , Face/anatomy & histology , Face/surgery , Fascia/anatomy & histology , Fasciotomy , Rhytidoplasty/methods , Humans
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