Stand-alone optical spinning tweezers with tunable rotation frequency

Advances in optical trapping design principles have led to tremendous progress in manipulating nanoparticles (NPs) with diverse functionalities in different environments using bulky systems. However, efficient control and manipulation of NPs in harsh environments require a careful design of contactless optical tweezers. Here, we propose a simple design of a fibered optical probe allowing the trapping of dielectric NP as well as a transfer of the angular momentum of light to the NP inducing its mechanical rotation. A polarization conversion from linearly-polarized incident guided to circularly transmitted beam is provoked geometrically by breaking the cylindrical symmetry of a coaxial nano-aperture that is engraved at the apex of a tapered metal coated optical fiber. Numerical simulations show that this simple geometry tip allows powerful light transmission together with efficient polarization conversion. This guarantees very stable trapping of quasi spherical NPs in a non-contact regime as well as potentially very tunable and reversible rotation frequencies in both directions (up to 45 Hz in water and 5.3 MHz in air for 10 mW injected power in the fiber). This type of fiber probe opens the way to a new generation of miniaturized tools for total manipulation (trapping, sorting, spinning) of NPs.

Expression of caveolin-1 in tooth germ, ameloblastoma and ameloblastic carcinoma

BACKGROUND

The caveolin-1 protein (structural component of membrane caveolae) plays important roles in several biological functions, such as endocytosis, cell adhesion, and cell signaling. However, this protein has been associated with mechanisms of tumorigenesis in several neoplasms. The expression patterns and roles of caveolin-1 in the oral epithelium and in embryonic and odontogenic tumor tissues are still unclear.

MATERIAL AND METHODS

The expression of caveolin-1 was evaluated in samples of the normal gingival epithelium (n=7), human tooth germ (TG) (n=12), ameloblastoma (AM) (n=83), and ameloblastic carcinoma (AC) (n=9) by immunohistochemistry. Additionally, AM samples were analyzed by qRT-PCR and Western blot.

RESULTS

Most TG (91.7%), AM (73.5%) and AC (100%) samples showed diverse patterns of immunohistochemical positivity for caveolin-1, while only one gingival sample was positive. The transcript levels of cav-1 were significantly upregulated by 14.9-fold in AM tissue (P = 0.0014) compared to those in normal gingival epithelial tissue, as shown by qRT-PCR. Presence of caveolin-1 protein was confirmed by Western blot analysis. The caveolin-1 immunoexpression patterns throughout the stages of TG show its importance during odontogenesis.

CONCLUSIONS

The overexpression of caveolin-1 in AM and AC compared to its expression in normal gingival epithelium (adult tissue) suggests a possible role of caveolin-1 in protumoral events, but due to the similar immunoexpression observed in AM and AC, caveolin-1 may not necessarily participate in the malignant transformation process. However, future studies are needed to clarify and confirm these hypotheses.

0787 Autonomic Dysfunction and Phenoconversion in Idiopathic/Isolated REM Sleep Behavior Disorder

Introduction

REM-sleep behavior disorder (RBD) is a common finding among patients with synucleinopathies. We aimed to determine the degree of autonomic dysfunction in patients presenting with idiopathic RBD (iRBD), and the predictive value of autonomic dysfunction for phenoconversion to a defined neurodegenerative disease.

Methods

We searched our electronic medical record for patients diagnosed with iRBD who also underwent standardized autonomic function testing within 6 months of iRBD diagnosis, and who had clinical follow-up of at least 3 years following iRBD diagnosis. Patients who received a diagnosis of phenoconversion within 3 months of autonomic testing were excluded. The composite autonomic severity score (CASS) was derived and compared between phenoconverters and non-converters using chi-square and Wilcoxon rank-sum tests.

Results

We identified 18 patients who fulfilled in- and exclusion criteria. Average age at autonomic testing was 67 ± 6.6 years. Twelve (67%) patients phenoconverted during the follow-up period; 6 developed PD, the other 6 DLB. Fifteen (83%) patients had at least mild autonomic dysfunction. There were no significant differences between overall converters and non-converters in total CASS or CASS subscores. However, iRBD patients who developed DLB had significantly higher total and cardiovagal CASS scores compared with those who developed PD (p <0.05), and a trend for higher adrenergic CASS scores compared to those who developed PD and those who did not phenoconvert (p=0.08 for each).

Conclusion

Autonomic dysfunction was seen in 83% of iRBD patients, and more severe baseline cardiovagal and adrenergic autonomic dysfunction in iRBD was associated with phenoconversion to DLB but not PD. Prospective studies are needed to confirm the value of autonomic testing for predicting phenoconversion and disease phenotype in iRBD.

Support

 

Abstract P5-22-10: Intraoperative ultrasound guided surgery after neoadjuvant treatment in breast cancer improves patient´s quality of life

Background: Intraoperative ultrasound guided surgery (IOUS) has shown not only to improve surgical outcomes by achieving higher rates of negative margins and reducing the need for re-excisions, but also showing better cosmetic results and patient's satisfaction in the adjuvant setting. After neoadjuvant treatments (NAT) we have shown that IOUS lowers the volume of resection in patients with pathologic complete response or minimal microscopic disease after NAT without compromising margins and local recurrences when compared to wire localization techniques (WL) The aim of this study was to determine if IOUS after NAT contributes to improve cosmetic outcomes and quality of life (QOL) when compared with WL.

Material and Methods. The pilot study enrolled patients treated with NAT who underwent breast-conserving surgery (BCS) between July 2008 and December 2012. On the follow up visit, cosmetic outcomes were assessed by the patient and surgeon on a 4 point Likert scale, by the Breast Cancer Conservative Treatment cosmetic results (BCCT.core) software, and by an independent panel. QOL was assessed using cancer-specific (EORTC QLQ-C30 and EORTC QLQ-B23) questionnaires.

Results. The study investigated 113 patients: 81 (71.6 %) in the IOUS group and 32 (28.3 %) in the WL group. The patient and tumor characteristics were comparable between the two groups. Mean follow up was 64 months (range, 12-90) in the WL group while 41 months (range, 18-107) in the IOUS group.

Cosmetic outcomes reported by the patient showed a tendency (p=0.07) for better results in the IOUS group. Patient reported cosmetic outcomes and the independent panel cosmetic evaluation significantly correlated with lumpectomy volume excised (p= 0.04, p = 0.02 respectively). The BCCT.core did not correlate with volume of tissue excised (p < 0.14). IOUS achieved better cosmetic outcomes compared to WL, with excellent outcomes of 30% and 19% respectively, although poor cosmetic outcomes were 3% and 0% respectively. Correlation between patients and surgeons evaluation regarding cosmetic outcomes and satisfaction was low (0.38 and 0.40 respectively). A comparison of the QOL scores of 113 patients showed a significantly better global health status (p = 0.03), better emotional and role function (p = 0.004), for patients with IOUS compared to WL patients.

Conclusions. This is the first study to show that breast volume excised significantly correlates with cosmetic outcomes in the neoadjuvant setting. These results suggest that IOUS after NAT contributes to a better quality of life and may influence cosmetic outcomes in breast cancer patients. Patient reported outcomes should be included in the quality assessment in breast surgery as the correlation with surgeons' evaluation is low.

Citation Format: Rubio IT, Rodriguez R, Esgueva-Colmenarejo A, Suarez M, Espinosa-Bravo M, Siso C, Cordoba O, Alvarado S, Volders J, Van Den Tol P. Intraoperative ultrasound guided surgery after neoadjuvant treatment in breast cancer improves patient´s quality of life [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P5-22-10.

Patterns of biofilm structure and formation kinetics among Acinetobacter baumannii clinical isolates with different antibiotic resistance profiles

This study evaluates the rates of biofilm formation in light of the different characteristics of twelve A. baumannii clinical isolates.

Impact of constitutional polymorphisms in VCAM1 and CD44 on CD34+ cell collection yield after administration of granulocyte colony-stimulating factor to healthy donors

Background The number of CD34(+) cells mobilized from bone marrow to peripheral blood after administration of granulocyte colony-stimulating factor varies greatly among healthy donors. This fact might be explained, at least in part, by constitutional differences in genes involved in the interactions tethering CD34(+) cells to the bone marrow.

DESIGN AND METHODS

We analyzed genetic characteristics associated with CD34(+) cell mobilization in 112 healthy individuals receiving granulocyte colony-stimulating factor (filgrastim; 10 μg/kg; 5 days).

RESULTS

Genetic variants in VCAM1 and in CD44 were associated with the number of CD34(+) cells in peripheral blood after granulocyte colony-stimulating factor administration (P = 0.02 and P = 0.04, respectively), with the quantity of CD34(+) cells ×10⁶/kg of donor (4.6 versus 6.3; P < 0.001 and 7 versus 5.6; P = 0.025, respectively), and with total CD34(+) cells ×10⁶ (355 versus 495; P = 0.002 and 522 versus 422; P = 0.012, respectively) in the first apheresis. Of note, granulocyte colony-stimulating factor administration was associated with complete disappearance of VCAM1 mRNA expression in peripheral blood. Moreover, genetic variants in granulocyte colony-stimulating factor receptor (CSF3R) and in CXCL12 were associated with a lower and higher number of granulocyte colony-stimulating factor-mobilized CD34(+) cells/μL in peripheral blood (81 versus 106; P = 0.002 and 165 versus 98; P=0.02, respectively) and a genetic variant in CXCR4 was associated with a lower quantity of CD34(+) cells ×10⁶/kg of donor and total CD34(+) cells ×10⁶ (5.3 versus 6.7; P = 0.02 and 399 versus 533; P = 0.01, respectively). Conclusions In conclusion, genetic variability in molecules involved in migration and homing of CD34(+) cells influences the degree of mobilization of these cells.

Human immunodeficiency virus testing uptake and risk behaviours in Spain

BACKGROUND

The purpose of this study was to estimate the prevalence of human immunodeficiency (HIV) testing in the general population; to analyse factors related to voluntary testing; and to describe the main reasons for testing, the kinds of health services where testing takes place and the relations between self-risk perception and HIV testing.

METHODS

A probability sample survey of health and sexual behaviour in men and women aged 18-49 years and resident in Spain in 2003 (n = 10 980) was used. A combination of face-to-face and computer-assisted self-interview was used, and bivariate and multivariate logistic regression analyses were performed.

RESULTS

Some 39.4% (40.2% in men and 38.5% in women) had ever been tested, blood donation being the main reason for men and pregnancy for women. In the multivariate analysis, HIV testing was associated with foreign nationality, high educational level, having injected drugs and having a large number of sexual partners. In men, it was also associated with age 30-39 years, having had sex with other men and having paid for sex. About 29.3% of men and 32.8% of women had their last voluntary HIV test in primary healthcare centres, whereas only 3.4% of men and 3.6% of women had last been tested in sexually transmitted infection/HIV diagnostic centres. About 20.2% of men and 5.5% of women with risk behaviours had never been tested.

CONCLUSION

The proportion of men with risk behaviours who have never had an HIV test is unacceptably high in Spain. Scaling up access to HIV testing in this population group remains a challenge for health policies and research.

Mechanical, tribological, and biocompatibility properties of ZrN-Ag nanocomposite films

Nanocomposite films of ZrN-Ag were produced by reactive unbalanced magnetron sputtering, and their structural, chemical, mechanical, tribological, haemocompatibility, and antibacterial properties were studied as a function of film composition. The films formed a dense and homogeneous microstructure whereby nanocrystals of Ag are distributed evenly throughout the ZrN matrix. For small additions of silver, the hardness was found to increase, whereas the elastic modulus was found to decrease drastically. In the process of optimizing the deposition conditions, three kinds of coatings were prepared on 316 L surgical steel and tested by accelerated electrochemical polarization tests in order to detect the influence of Ag and the value of the bias potential on the corrosion performance of the system. Films produced under the optimum deposition conditions were, subsequently, deposited on medical grade Ti-Al-V and worn against ball-bearing steel using a ball-on-disk tribotester in bovine serum and were found to have superior tribological properties compared with single-phase ZrN coatings. The haemocompatibility of the films was assessed by investigating the adsorption of human serum albumin and fibrinogen on samples with different phase compositions. Quantification of the protein adsorption was carried out using spectroscopic ellipsometry, which confirmed the haemocompatibility of the films. Antibiotic activity of the films was quantified by incubating the films in bacterial cultures, namely, Staphylococcus epidermis, Staphylococcus aureus, and Escherichia coli. Films with a silver content > 10% exhibited superior antibacterial activity compared with the uncoated samples.

Systematic review: Proton pump inhibitor-associated acute interstitial nephritis

BACKGROUND

A number of recent case reports and case series suggest that proton pump inhibitors may cause acute interstitial nephritis.

AIM

To establish the nature of the relationship (cause or association) between proton pump inhibitor use and development of interstitial nephritis.

DATA COLLECTION

Two researchers independently searched electronic databases (MEDLINE, EMBASE, GOOGLE, LILACS, COCHRANE) for articles from 1970 to 2006, including all study designs, populations and languages. Two independent reviewers assessed study quality and collected the data.

SELECTION CRITERIA

absence of baseline renal failure, development of interstitial nephritis after proton pump inhibitor exposure, nephritis confirmed by creatinine plus either renal biopsy or recurrence upon reinitiating proton pump inhibitor.

RESULTS

Sixty four cases (60% females, mean age 78 years) of proton pump inhibitor-associated interstitial nephritis were found, 60 included in this review (59 confirmed by renal biopsy, one by recurrence upon reinitiating proton pump inhibitor). The most common symptoms were non-specific. The mean proton pump inhibitor treatment duration before diagnosing nephritis was 13 weeks, average recovery time was 35.5 weeks, one patient required permanent dialysis, there were no deaths.

CONCLUSION

Proton pump inhibitor-related interstitial nephritis is rare, idiosyncratic and difficult to predict. It requires a high level of clinical suspicion. While there is not sufficient evidence to establish a causal relationship with certainty, there does appear to be a low-prevalence association.

Activation of nuclear factor-kappa B is linked to resistance to neoadjuvant chemotherapy in breast cancer patients

The nuclear factor (NF)-kappaB system is a promising anticancer target due to its role in oncogenesis and chemoresistance in preclinical models. To provide evidence in a clinical setting on the role of NF-kappaB in breast cancer, we aimed to study the value of basal NF-kappaB/p65 in predicting resistance to neoadjuvant chemotherapy, and to characterise the pharmacodynamic changes in NF-kappaB/p65 expression following chemotherapy in patients with locally advanced breast cancer. Pre- and post-chemotherapy tumour specimens from 51 breast cancer patients treated with anthracycline- and/or taxane-containing neoadjuvant chemotherapy were assayed by immunohistochemistry for NF-kappaB/p65 subcellular expression. We studied NF-kappaB/p65, a well-characterised member of the NF-kappaB family that undergoes nuclear translocation when NF-kappaB is activated. Activation of NF-kappaB (i.e. nuclear NF-kappaB/p65 staining in pre-therapy specimens) was linked to chemoresistance. Patients with NF-kappaB/p65 nuclear staining in pre-treatment samples had a 20% clinical response rate, while patients with undetected nuclear staining had a 91% response rate to chemotherapy (P = 0.002). Notably, four patients achieved a complete histological response and none of them had pre-treatment NF-kappaB/p65 nuclear staining. Moreover, the number of patients with NF-kappaB/p65 activation increased after chemotherapy exposure. It is concluded that NF-kappaB/p65 activation assayed by immunohistochemistry is a predictive factor of resistance to neoadjuvant chemotherapy in breast cancer patients. Moreover, NF-kappaB activation was inducible following chemotherapy in a proportion of breast cancer patients. These novel clinical findings strengthen the rationale for the use of NF-kappaB inhibitors to prevent or overcome chemoresistance in breast cancer.

Increased immunohistochemical expression of thrombomodulin at placental perivascular myofibroblast in severe preeclampsia (PE)

The presence of pro-coagulant and anti-coagulant components of the placental vascular endothelium and syncytiotrophoblast are essential for homeostasis. Vascular endothelium prevents blood clot formation in vivo by involving a cell surface thrombin-binding glycoprotein, thrombomodulin (TM), that activates plasma anti-coagulant protein C. The TM levels increase during pregnancy, but the fibrinolytic capacity diminishes. Since vascular lesions with placental coagulation disorders can be associated with preeclampsia (PE), we hypothesized that TM expression in the stem villous vasculature and syncytiotrophoblast of the placenta are impaired in PE. Plasma and placental tissue samples were collected from PE (n=12) and normotensive pregnant patients (n=11). Patient's gestational age was 35.7+/-1.2 (normotensive) and 30.6+/-1.5 weeks (PE). Blood samples were drawn 30 min before delivery. Serum PAI-1 and PAI-2 antigens were determined by enzyme-linked immunoabsorbent assay (ELISA). A monoclonal antibody specific for TM was used for immunohistochemical tissue staining (ABC) and the staining was quantified by semi quantitative scores. Results show no intensity differences at the apical syncytiotrophoblast between the two groups. However, in preeclamptic placenta, TM expression diminished in the endothelium of the stem villi arteries and increased in the perivascular and stromal myofibroblats in cases of severe PE. TM changes were associated with an increased PAI-1/PAI-2 ratio. It is suggested that in severe PE, the decreased placental blood flow may be due to structural and functional impairment of the endothelium of the stem villi vessels and the surrounding perivascular and stromal myofibroblast, by increasing TM expression which may modulate fetal blow flow in the villous tree.

Sclerosing mesenteritis in small bowel transplantation: possible manifestation of acute vascular rejection

BACKGROUND

Acute rejection of human small bowel allografts is characterized by clinical symptoms combined with characteristic morphologic alterations. The typical geographic distribution of acute rejection in the bowel is involvement of the intestinal parenchyma, which can be transmural, particularly when the rejection is more severe. However, little is known concerning the potential for donor-derived soft tissue adjacent to the bowel to become involved by the host alloimmune response.

METHODS

We describe a male patient who, several weeks after combined small bowel and liver transplantation, demonstrated sclerosing mesenteritis with vasculitis and acute rejection of the bowel.

RESULTS

The vascular lesions in the mesentery demonstrated increased IgG deposition and the patient developed an alloantibody to the donor.

CONCLUSIONS

The changes described herein may represent a novel presentation of acute vascular rejection.

Simple sequence repeat marker diversity in cassava landraces: genetic diversity and differentiation in an asexually propagated crop

Cassava (Manihot esculenta) is an allogamous, vegetatively propagated, Neotropical crop that is also widely grown in tropical Africa and Southeast Asia. To elucidate genetic diversity and differentiation in the crop's primary and secondary centers of diversity, and the forces shaping them, SSR marker variation was assessed at 67 loci in 283 accessions of cassava landraces from Africa (Tanzania and Nigeria) and the Neotropics (Brazil, Colombia, Peru, Venezuela, Guatemala, Mexico and Argentina). Average gene diversity (i.e., genetic diversity) was high in all countries, with an average heterozygosity of 0.5358 +/- 0.1184. Although the highest was found in Brazilian and Colombian accessions, genetic diversity in Neotropical and African materials is comparable. Despite the low level of differentiation [F(st)(theta) = 0.091 +/- 0.005] found among country samples, sufficient genetic distance (1-proportion of shared alleles) existed between individual genotypes to separate African from Neotropical accessions and to reveal a more pronounced substructure in the African landraces. Forces shaping differences in allele frequency at SSR loci and possibly counterbalancing successive founder effects involve probably spontaneous recombination, as assessed by parent-offspring relationships, and farmer-selection for adaptation.

Expression of a plant-derived peptide harboring water-cleaning and antimicrobial activities

Drinking water is currently a scarce world resource, the preparation of which requires complex treatments that include clarification of suspended particles and disinfection. Seed extracts of Moringa oleifera Lam., a tropical tree, have been proposed as an environment-friendly alternative, due to their traditional use for the clarification of drinking water. However, the precise nature of the active components of the extract and whether they may be produced in recombinant form are unknown. Here we show that recombinant or synthetic forms of a cationic seed polypeptide mediate efficient sedimentation of suspended mineral particles and bacteria. Unexpectedly, the polypeptide was also found to possesses a bactericidal activity capable of disinfecting heavily contaminated water. Furthermore, the polypeptide has been shown to efficiently kill several pathogenic bacteria, including antibiotic-resistant isolates of Staphylococcus, Streptococcus, and Legionella species. Thus, this polypeptide displays the unprecedented feature of combining water purification and disinfectant properties. Identification of an active principle derived from the seed extracts points to a range of potential for drinking water treatment or skin and mucosal disinfection in clinical settings.

[PREVALENCE OF HBsAg AND anti-HBs CARRIERS IN PREGNANT WOMEN WHO RESIDE IN DIFFERENT ENDEMIC AREAS LOCATED IN CENTRAL-SOUTHERN DEPARTAMENTS OF PERU]

The present study was performed to estimate the prevalence of HBV in pregnant women (mean age among groups 25,0 6,9) who live in areas of different endemicity, and located in the Departments of Lima, Junin, Apurimac, and Ayacucho in Peru. All studies were carried out using radioimmunological techniques. In the Instituto Materno Perinatal in Lima, located in a low endemical area, 2086 pregnant women whose ages ranged between 14 and 44 years were evaluated (for laboratory tests) at their first prenatal examination. A prevalence of 9,38% (HbsAG+), 0,38% (Ratio), and 3,18% (HBsAg+, anti-HBsAg+) was found, corresponding to 107 HBsAg+ pregnant women whose treated newborn wouId prevent the HBV chronic infection of approximate 21 newborn each year. 63% HBsAg+ pregnant women were born in Departments other than Lima. In the Hospital de Apoyo La Merced, located in Chanchamayo, Junin, which is a medium endemic area, 217 pregnant women whose ages ranged between 14 and 48 years were evaluated. The prevalence found in this Hospital was of 1,38% (HBsAg+), 1,2% (Ratio), and 17,8% (HBsAg+, anti-HBs+). All positive HBsAg were negative for HBeAg. The projection of results corresponded to a total of 9 HbsAg+ pregnant women and 2 newborn preventive of chronic disease per year. In the Guillermo D az de la Vega Hospital in Abancay, Apurimac, located in a medium to high endemic area, 221 pregnant women whose ages ranged between 15 and 46 years were evaluated. A prevalence of 1,36% (HBsAg+), 1,0% (Ratio), and 36,16% (HBsAg+, anti-HBs+) was found. All positive HBsAg were negative for HBeAg. Projected results corresponded to a total of 37 HBsAg+ pregnant carriers and 7 newborn preventive of chronic disease per year. The Hospital General de Huanta, in Ayacucho, located in a high endemicity area, presented a prevalence of 3,2% (HBsAg+), 1,9% (Ratio), and 76,2% (HBsAg+, anti-HBs+) from 126 pregnant women evaluated with ages between 15 and 48 years old. These results gave a total projection per year of 39 HBsAg+ pregnant women and 8 newborn preventive of chronic hepatic disease. Among a total of 4 positive HBsAg cases, 3 positive pregnant women were studied for HBeAg. All 3 were negative. These results establish the prevalence of HbsAg and antiHBs in pregnant women from different endemical areas with significant prevalence in the Departments of Ayacucho (Huanta), and Apurimac (Abancay). They also contribute towards the costbenefit analysis for the prevention of HBV chronic infection.

Foreign body granuloma mimicking intracranial meningioma: case report and review of the literature

OBJECTIVE AND IMPORTANCE

Intracranial foreign body granulomas are rare. We describe a case of an intracranial foreign body granuloma found in a 17-year-old female patient 9 years after she underwent a craniotomy for a tumor of unknown type. Postoperative imaging of patients who have undergone neurosurgical procedures can often reveal enhancing masses, and foreign body granuloma should be included in the differential diagnosis.

CLINICAL PRESENTATION

The patient presented with a history of developmental delay, panhypopituitarism, and chronic headache. Admission resulted from an acute increase in the severity of her headache.

INTERVENTION

Imaging studies, including computed tomography and magnetic resonance imaging, demonstrated a 1.5 x 2 cm round, enhancing anterior interhemispheric mass, appearing to arise from the falx and causing mild mass effect. A nonenhancing cystic mass was also noted in the suprasellar region but was without mass effect. The patient underwent a craniotomy and removal of the anterior mass without complication, and her headache resolved. A pathological examination of the specimen confirmed the diagnosis of foreign body granuloma.

CONCLUSION

Although rare, foreign body granuloma should be included in the differential diagnosis of previously operated intracranial masses. The importance of accurate historical information and guidelines that may assist in diagnosis are discussed.

Mass spectral fragmentation patterns of new 5-acetyl-4-aryl-6-methyl-2(1H)pyridones

The electron impact mass spectra of new 5-acetyl-4-aryl-6-methyl-2(1H)pyridones have been studied. A dominant peak in all the spectra is due to cleavage of the CO-NH bond of the amido group with charge retention on the carbonyl group. This fragmentation is followed by a hydrogen rearrangement to the nitrogen atom forming ketene intermediates; this pathway leads to a highly stabilized ion which constitutes the base peak in the spectra in most of the compounds studied. Copyright 1999 John Wiley & Sons, Ltd.

Improved outcome of cytomegalovirus retinitis in AIDS patients after introduction of protease inhibitors

The objective of this study was to evaluate the influence of protease inhibitor therapy on the rate of progression and survival of 17 AIDS patients with stable Cytomegalovirus retinitis, who were receiving anti-CMV therapy. CD4+ count, HIV load, and CMV antigenemia assay were determined at baseline, at the first month, and every 3 months thereafter. Median CD4+ count increased from 11 to 87 cells/mm3, and median HIV RNA level decreased from 4.96 to 3.28 log10 copies/ml, after 6 months on therapy. Although 9 patients (53%) relapsed in a median time of 97 days (range, 15-152 days), no further episodes were observed during a median follow-up of 17 months (range, 5-18 months). Thus, the probability of remaining free of relapse was twofold higher than that observed in matched patients who did not receive protease inhibitors. Median CD4+ count at the 3rd month was higher in those individuals who went on to progress (p = .03), and a positive result to a CMV antigenemia test was associated with progression of retinitis (relative hazard, 4.45; p = .04). Survival rate was 94% at 17 months (89% increase). Therefore, protease inhibitor therapy reduces retinitis progression and improves survival. However, the immunologic response may not provide initial sufficient protection to avoid, or even may play a role on, early CMV progression.

Small volume fat transfer

BACKGROUND

The use of autologous fat has been advocated for tissue augmentation for over a century. However, this technique remains controversial and many investigators have made suggestions to increase its potential.

OBJECTIVES

To develop a less traumatic method to collect, purify, and reinject fat to obtain more dramatic augmentations for the cosmetic improvement of contours and tissue defects.

METHODS

Fat was collected from the donor site following tumescent infiltration of tissue. A "vented" syringe with an atraumatic Mercedes tip was used to collect the fat and, after washing with lactated Ringers or saline, the fat was transferred to small syringes for controlled injections. Small filaments of fat were placed in multi-layers throughout the area of the defect or area of desired contour change. The unused fat was frozen for a second or third injection session.

RESULTS

The fat transfer method yielded augmentations of 40%-120% of injected volume in the 339 areas treated. After 45-60 days, the implant was stabilized and remained for the length of our study (up to 10 years). In several cases excessive fat had to be removed. Other than slight bruising, occasional divots at the donor site, and three cases of bacterial infection, the autologous tissue transfer was an uncomplicated event.

CONCLUSION

Fat grafting has proven to be a safe and effective procedure for correcting and enhancing tissue defects and contour deficiencies.

A novel occlusive dressing for skin resurfacing

BACKGROUND

Over the last decade the benefits of occlusive dressings have been appreciated. These dressings allow the epithelium to resurface easier. The wound heals quicker.

OBJECTIVE

To evaluate a new silicone sheeting for immediate post-op wound care. Our objective was to determine its benefit in the wound care management after laser skin resurfacing.

METHOD

The silicone sheeting was applied immediately after laser resurfacing in 35 individuals. This temporary skin replacement was held in place with 4 x 4 gauzes and tube gauze netting. Although the tube netting and the 4 x 4 gauzes were changed daily the silicone sheeting remained in place for 4 or 5 days. Following this, applications of a petrolatum-based ointment were continued for another 5 days. At day 10 the skin care program was changed to a moisturizing sunscreen. Bleaching cream was added at day 15 in darker complexed individuals.

RESULTS

The dressing accelerated wound healing. Pain and swelling were minimized under the sheeting. Histologic examinations demonstrated a more rapid reepithelialization at these treated sites. Other than technical problems, such as the riding up of the dressing over the jawline or retraction of the dressing off the lips or off the eyelids, there were no adverse sequelae. The wound healed rapidly and allowed the rapid progression to the application of a moisturizer-sunscreen or a skin-bleaching cream. Other than these technical problems there were no complications. No wound infections were noted.

CONCLUSION

The use of silicone sheeting following skin resurfacing facilitated a rapid reepithelialization of treated areas. There was a remarkable reduction in erythema and edema accompanying the use of the dressing. The program made it possible for patients to return to work in 12-15 days.

Deletion of the Saccharomyces cerevisiae gene RAD30 encoding an Escherichia coli DinB homolog confers UV radiation sensitivity and altered mutability

The dinB gene of Escherichia coli is an SOS-inducible gene of unknown function. Its mode of regulation and the amino acid sequence similarity of the predicted DinB protein to the UmuC protein of E. coli both suggest a role in cellular responses to DNA damage and probably in error-prone repair. Proteins with sequence similarity to DinB have been predicted from genes cloned from various prokaryotic and eukaryotic organisms, including Caenorhabditis elegans. Here we present the phenotypic characterization of a haploid Saccharomyces cerevisiae strain deleted for the ORF YDR419W, encoding a yeast DinB homolog. The deletion mutant is viable but is moderately sensitive to killing following exposure to ultraviolet (UV) radiation. Hence, we have named the gene RAD30. Steady-state levels of RAD30 transcripts are increased following UV irradiation. UV-induced locus-specific reversion of an ochre allele (arg4-17) is reduced in the rad30 deletion mutant. However, enhanced mutability was observed following treatment with the alkylating agent methylmethanesulfonate (MMS). Spontaneous mutability was also slightly increased. We conclude that RAD30 encodes an accessory function involved in DNA repair and mutagenesis. We speculate that the relatively weak phenotype and the opposite effects on mutability as a function of the type of DNA damage involved may derive from a functional redundancy of yeast proteins which facilitate replicative bypass of non-coding DNA lesions.

Identification of peripheral vascular disease in elderly subjects using optical spectroscopy

The purpose of this study was to determine the usefulness of near-infrared spectroscopy (NIRS) measurements to identify peripheral vascular disease (PVD). Usefulness was determined by the frequency of a successful test, as well as comparison with standard clinical assessments. Study subjects (N = 117, mean age = 67.8 +/- 8.1 yrs) responded to a free screening for PVD. NIRS was used to measure the relative O2 saturation of hemoglobin in the soleus muscle. The time to 1/2 recovery of O2 saturation (O2T1/2) was measured after 1 minute of repeated plantar flexions using a Cybex Eagle seated calf machine. O2T1/2 was used as many subjects had recovery curves that did not have an exponential line shape. The test was done on both legs and the worst leg was used for analysis. For comparative purposes, a clinical history and physical examination were performed by a physician or nurse practitioner, which included questions on intermittent claudication, examination of peripheral pulses, and questions to identify cardiovascular risk factors. NIRS signals were obtained on 105 of 117 subjects (89% success rate). Subjects with body mass index (BMI) values above 32 appeared to have NIRS O2T1/2 values that were less reliable than subjects with BMI values < or = 32 (77% success rate). The O2T1/2 was longer in subjects with claudication and reduced pulses than in subjects without these conditions. Sensitivity comparing O2T1/2 to claudication and reduced pulse varied from 51-76% and specificity from 65-80%, depending on the cutoff value for O2T1/2 that was used (normal value plus 1 or 2 SD). A longer O2T1/2 was significantly associated with incidence of diabetes, smoking, hypercholesterol, and coronary bypass surgery. In summary, successful NIRS O2T1/2 measurements were made in 77% of the subjects, with failure primarily occurring in obese subjects. NIRS O2T1/2 measurements showed reasonable although not strong agreements with clinical assessment of PVD, and with some risk factors for cardiovascular disease.