Fabric Classification Using a Finger-Shaped Tactile Sensor via Robotic Sliding

Tactile sensing endows the robots to perceive certain physical properties of the object in contact. Robots with tactile perception can classify textures by touching. Interestingly, textures of fine micro-geometry beyond the nominal resolution of the tactile sensors can also be identified through exploratory robotic movements like sliding. To study the problem of fine texture classification, we design a robotic sliding experiment using a finger-shaped multi-channel capacitive tactile sensor. A feature extraction process is presented to encode the acquired tactile signals (in the form of time series) into a low dimensional (≤7D) feature vector. The feature vector captures the frequency signature of a fabric texture such that fabrics can be classified directly. The experiment includes multiple combinations of sliding parameters, i.e., speed and pressure, to investigate the correlation between sliding parameters and the generated feature space. Results show that changing the contact pressure can greatly affect the significance of the extracted feature vectors. Instead, variation of sliding speed shows no apparent effects. In summary, this paper presents a study of texture classification on fabrics by training a simple k-NN classifier, using only one modality and one type of exploratory motion (sliding). The classification accuracy can reach up to 96%. The analysis of the feature space also implies a potential parametric representation of textures for tactile perception, which could be used for the adaption of motion to reach better classification performance.

The efficacy and safety of rotavirus vaccines in countries in Africa and Asia with high child mortality

Rotavirus remains a leading cause of diarrhoeal morbidity and mortality in young children and rotavirus vaccines are critical for reducing global disease burden. This report addresses the performance of rotavirus vaccines in countries with high child mortality. We performed a sensitivity analysis as part of a systematic review on rotavirus vaccines to inform development of World Health Organization vaccine recommendations. The efficacy of four prequalified vaccines against severe rotavirus gastroenteritis was similar across high mortality settings in Asia and Africa. Within the first year following vaccination, vaccine efficacy for the four vaccines ranged from 48% to 57% while in the second year, efficacy ranged from 29% to 54%. The four vaccines showed no increase in intussusception risk in these settings. All four vaccines appear to prevent significant numbers of severe rotavirus gastroenteritis episodes with no measurable increase in intussusception risk in high mortality settings in Africa and Asia.

Disrupting a phospholipase A2 gene increasing lipid accumulation in the oleaginous yeast Yarrowia lipolytica

AIMS

Phospholipase A₂ (PLA₂ ) is a diverse superfamily that hydrolyzes fatty acyl ester bonds at the sn-2 position of phospholipids. The correlation between phospholipid metabolism and the anabolism of neutral lipids remains unclear in yeasts. This study aims to explore the effects of PLA₂ on lipid accumulation in the oleaginous yeast Yarrowia lipolytica.

METHODS AND RESULTS

This study identified an actively expressed phospholipase A₂ gene (PLA2-3, YAIL0_E16060g) in Y. lipolytica by quantitative PCR analysis. The gene PLA2-3 was disrupted in the strain po1gΔKu70 by homologous recombination and in the strain po1g-G3 by a CRISPR-Cas9 system, which caused an increase in stress sensitivity while the cell growth was not altered under fermentative conditions. Lipid production was performed in both flasks and bioreactors. The results showed that the lipid titre and lipid content were improved over 25% and 8-30%, respectively, in PLA2-3 disrupted strains compared to the controls.

CONCLUSIONS

Disruption of the phospholipase PLA2-3 gene could effectively improve lipid production in Y. lipolytica.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study presented a strategy on improving the lipid production of oleaginous yeasts and a similar strategy might be used in other oleaginous microbes.

How I investigate Clonal cytogenetic abnormalities of undetermined significance

Myelodysplastic syndromes are a group of hematopoietic stem cell diseases characterized by cytopenia(s), morphological dysplasia, and clonal hematopoiesis. In some patients, the cause of cytopenia(s) is uncertain, even after thorough clinical and laboratory evaluation. Evidence of clonal hematopoiesis has been used to support a diagnosis of myelodysplastic syndrome in this setting. In patients with cytopenia(s), the presence of clonal cytogenetic abnormalities, except for +8, del(20q) and -Y, can serve as presumptive evidence of myelodysplastic syndrome. Recent advances in next-generation sequencing have detected myeloid neoplasm-related mutations in patients who do not meet the diagnostic criteria for myelodysplastic syndrome. Various terms have been adopted to describe these cases, including clonal hematopoiesis of indeterminate potential (CHIP) and clonal cytopenia of undetermined significance (CCUS). Similarly, studies have shown that certain chromosomal abnormalities, including ones commonly detected in myelodysplastic syndrome, may not be associated necessarily with an underlying myelodysplastic syndrome. These clonal cytogenetic abnormalities of undetermined significance (CCAUS) are similar to CHIP and CCUS. Here, we review the features of CCAUS, distinguishing CCAUS from clonal cytogenetic abnormalities associated with myelodysplastic syndrome, and the potential impact of CCAUS on patient management.

Anti-HMGB1 antibody reduces weight gain in mice fed a high-fat diet

Insulin resistance in obesity is believed to be propagated by adipose tissue and liver inflammation. HMGB1 is a multifunctional protein that is pro-inflammatory when released from cells. It has been previously demonstrated that anti-HMGB1 antibody reduces atherosclerotic lesion pro-inflammatory cells and progression of atherosclerosis in a mouse model. To test the potential beneficial role of blocking HMGB1 in adipose tissue and liver inflammation in mice fed an obesogenic diet, we administered anti-HMGB1 antibody to C57Bl/6 mice fed a high (60%)-fat diet. The mice were treated with weekly injections of an anti-HMGB1 antibody or anti-KLH antibody (isotype control) for 16 weeks. Mice that received the anti-HMGB1 antibody gained less weight than the control-treated animals. Anti-HMGB1 treatment also reduced hepatic expression of TNF-alpha and MCP-1, molecules that promote inflammation. However, adipose tissue inflammation, as measured by gene expression analyses and immunohistochemistry, did not differ between the two groups. There also were no differences in glucose or insulin tolerance between the two groups. When feeding mice a high-fat diet, these data suggest that HMGB1 may have a crucial role in weight gain and liver inflammation.

Flow cytometry immunophenotypic analysis of Philadelphia-negative myeloproliferative neoplasms: Correlation with histopathologic features

BACKGROUND

Compared with the proven utility of flow cytometry immunophenotyping (FCI) analysis in the workup of myelodysplastic syndromes (MDS), immunophenotypic alterations in myeloproliferative neoplasms (MPN) have been less studied and the potential utility of FCI is not defined.

METHODS

Bone marrow (BM) samples of 83 Philadelphia-negative MPN patients were assessed by multicolor FCI including 27 with essential thrombocythemia (ET); 17 polycythemia vera (PV); 33 primary myelofibrosis (PMF) and 6 MPN-unclassifiable (MPN-U). The time interval from initial diagnosis of MPN to FCI analysis was 18 months (0-370). Ninety-five age-matched MDS patients with a similar BM blast count were included for comparison.

RESULTS

Immunophenotypic alterations, either in CD34(+) cells or myelomonocytic cells, were detected in 82 of 83 (99%) MPN cases. FCI abnormalities were more frequently observed in cases with substantial myelofibrosis but not different between PMF and fibrotic stage of ET/PV. Furthermore, FCI abnormalities were more frequent in cases with ≥5% BM blasts and/or circulating blasts (P = 0.006); as well as cases with an abnormal karyotype (P = 0.036); but not associated with morphologic dysplasia or JAK2 mutation status. Comparing with MDS, FCI abnormalities were overall less pronounced in MPN cases (P = 0.001).

CONCLUSIONS

MPNs exhibit frequent immunophenotypic alterations, more pronounced in cases with adverse histopathologic features. These findings illustrate that immunophenotypic alterations are a part of constellational findings in MPN, and correlate progressively with disease stage. The study results also suggest a role of FCI in diagnosis of MPN and monitoring disease over time and after therapy.

Multi-color flow cytometric immunophenotyping for detection of minimal residual disease in AML: past, present and future

Current chemotherapeutic regimens achieve CR in a large percentage of patients with AML. However, relapse after CR remains a significant problem. The presence of leukemic cells at levels too low to be detected by conventional microscopy, termed minimal residual disease (MRD), has been associated with an increased risk of relapse and shortened survival. Detection of MRD requires the use of highly sensitive ancillary techniques. Multi-color flow cytometric immunophenotyping is a sensitive method for quick and accurate detection of MRD. Use of this method in patient management may result in lower rates of relapse and improved survival, and is an effective means of assessing novel therapeutic agents. This method can be used in the vast majority of patients with AML, regardless of the immunophenotypic, cytogenetic and molecular genetic abnormalities present. Unfortunately, conflicting data regarding optimum methods of measurement and reporting, as well as the expertize required to interpret results have limited broad application of this technique. We provide a broad overview of this technique, including its advantages and limitations, and discuss the methods employed at our institution. We also review several possible areas of future investigation.

Toll-like receptor alterations in myelodysplastic syndrome

Recent studies have implicated the innate immunity system in the pathogenesis of myelodysplastic syndromes (MDS). Toll-like receptor (TLR) genes encode key innate immunity signal initiators. We recently identified multiple genes, known to be regulated by TLRs, to be overexpressed in MDS bone marrow (BM) CD34+ cells, and hypothesized that TLR signaling is abnormally activated in MDS. We analyzed a large cohort of MDS cases and identified TLR1, TLR2 and TLR6 to be significantly overexpressed in MDS BM CD34+ cells. Deep sequencing followed by Sanger resequencing of TLR1, TLR2, TLR4 and TLR6 genes uncovered a recurrent genetic variant, TLR2-F217S, in 11% of 149 patients. Functionally, TLR2-F217S results in enhanced activation of downstream signaling including NF-κB activity after TLR2 agonist treatment. In cultured primary BM CD34+ cells of normal donors, TLR2 agonists induced histone demethylase JMJD3 and interleukin-8 gene expression. Inhibition of TLR2 in BM CD34+ cells from patients with lower-risk MDS using short hairpin RNA resulted in increased erythroid colony formation. Finally, RNA expression levels of TLR2 and TLR6, as well as presence of TLR2-F217S, are associated with distinct prognosis and clinical characteristics. These findings indicate that TLR2-centered signaling is deregulated in MDS, and that its targeting may have potential therapeutic benefit in MDS.

Trisomy 11 in myelodysplastic syndromes defines a unique group of disease with aggressive clinicopathologic features

Trisomy 11 in myelodysplastic syndromes (MDS) is rare, with undefined clinical significance and is currently assigned to the International Prognostic Scoring System (IPSS) intermediate-risk group. Over a 15-year period, we identified 17 MDS patients with trisomy 11 either as a sole abnormality (n=10) or associated with one or two additional alterations (n=7), comprising 0.3% of all MDS cases reviewed. Of 16 patients with Bone Marrow material available for review, 14 (88%) patients presented with excess blasts, 69% patients evolved to acute myeloid leukemia (AML) in a 5-month median interval and the median survival was 14 months. For comparison, we studied 19 AML patients with trisomy 11 in a noncomplex karyotype, of which, a substantial subset of patients had morphologic dysplasia, and/or preexisting cytopenia(s)/MDS. Genomic DNA PCR showed MLL partial tandem duplication in 5 of 10 MDS and 7 of 11 AML patients. A review of literature identified 17 additional cases of MDS with trisomy 11, showing similar clinicopathologic features to our patients. Compared with our historical data comprising 1165 MDS patients, MDS patients with trisomy 11 had a significantly inferior survival to patients in the IPSS intermediate-risk cytogenetic group (P=0.0002), but comparable to the poor-risk group (P=0.97). We conclude that trisomy 11 in MDS correlates with clinical aggressiveness, may suggest an early/evolving AML with myelodysplasia-related changes and is best considered a high-risk cytogenetic abnormality in MDS prognostication.

Gonorrhea in the HIV era: a reversal in trends among men who have sex with men

OBJECTIVES

Gonorrhea cases among men who have sex with men (MSM) declined in the early years of the HIV epidemic. We evaluated more recent trends in gonorrhea among MSM through the Centers for Disease Control and Prevention's Gonococcal Isolate Surveillance Project.

METHODS

Isolates and case information were collected from 29 US sexually transmitted disease (STD) clinics. Gonococcal urethritis cases among MSM were compared with those among heterosexual men, and cases among MSM in 1995 to 1999 were compared with earlier MSM cases.

RESULTS

Of 34,942 cases, the proportion represented by MSM increased from 4.5% in 1992 to 13.2% in 1999 (P < .001). Compared with heterosexuals, MSM were older, more often White, and more often had had gonorrhea previously, although fewer had had gonorrhea in the past year. MSM with gonorrhea in 1995 to 1999 were slightly older than those with gonorrhea in 1992 to 1994, and a higher proportion had had gonorrhea in the past year.

CONCLUSIONS

MSM account for an increasing proportion of gonococcal urethritis cases in STD clinics. Given recent evidence that gonorrhea may facilitate HIV transmission, these trends demand increased attention to safe sexual behaviors and reducing STDs among MSM.

Experience of healthcare workers taking postexposure prophylaxis after occupational HIV exposures: findings of the HIV Postexposure Prophylaxis Registry

OBJECTIVE

To collect information about the safety of taking antiretroviral drugs for human immunodeficiency virus (HIV) postexposure prophylaxis (PEP).

DESIGN

A voluntary, confidential registry.

SETTING

Hospital occupational health clinics, emergency departments, private physician offices, and health departments in the United States.

RESULTS

492 healthcare workers (HCWs) who had occupational exposures to HIV, were prescribed HIV PEP, and agreed to be enrolled in the registry by their healthcare providers were prospectively enrolled in the registry. Three hundred eight (63%) of 492 of the PEP regimens prescribed for these HCWs consisted of at least three antiretroviral agents. Of the 449 HCWs for whom 6-week follow-up was available, 195 (43%) completed the PEP regimen as initially prescribed. Forty-four percent (n=197) of HCWs discontinued all PEP drugs and did not complete a PEP regimen. Thirteen percent (n=57) discontinued > or =1 drug or modified drug dosage or added a drug but did complete a course of PEP Among the 254 HCWs who modified or discontinued the PEP regimen, the two most common reasons for doing so were because of adverse effects attributed to PEP (54%) and because the source-patient turned out to be HIV-negative (38%). Overall, 340 (76%) HCWs with 6-week follow-up reported some symptoms while on PEP: nausea (57%), fatigue or malaise (38%), headache (18%), vomiting (16%), diarrhea (14%), and myalgias or arthralgias (6%). The median time from start of PEP to onset of each of the five most frequently reported symptoms was 3 to 4 days. Only 37 (8%) HCWs with 6-week follow-up were reported to have laboratory abnormalities; review of the reported abnormalities revealed that most were unremarkable. Serious adverse events were reported to the registry for 6 HCWs; all but one event resolved by the 6-month follow-up visit. Fewer side effects were reported by HCWs taking two-drug PEP regimens than by HCWs taking three-drug PEP regimens.

CONCLUSIONS

Side effects from HIV PEP were very common but were rarely severe or serious. The nature and frequency of HIV PEP toxicity were consistent with information already available on the use of these antiretroviral agents. Clinicians prescribing HIV PEP need to counsel HCWs about PEP side effects and should know how to manage PEP toxicity when it arises.

Monitoring std prevalence and reproductive health care among high-risk adolescent women

Background: Urban adolescent women, particularly those in socially disadvantaged situations are at high risk for infections with Chlamydia trachomatis (CT), and Neisseria gonorrhoeae (GC) and their sequelae. Non-invasive screening technologies, including ligase chain reaction (LCR) and polymerase chain reaction (PCR) urine tests for CT and GC allow for provision of screening services in settings frequented by high-risk adolescents where such services have not been traditionally provided. In 1999, the CDC lead a multi-site project monitoring STD prevalence and reproductive health service, collecting a standard set of variables in women <20 yrs in juvenile justice system, drug treatment centers, and school-based clinics. This report provides preliminary data from Alabama and Colorado. Methods: Adolescent women who present for intake/services at selected facilities are enrolled in the project. In collaboration with CDC, sites developed a set of standard variables to be collected, including demographics, risk behaviors, symptoms, test performed, and test results. Dependent on services already performed, sites added CT and/or GC urine PCR/LCR and pregnancy testing to existing screening protocols.Results: In first 3-months, 533 adolescent women were enrolled in this on-going study; 379 in juvenile institutions, 38 in drug treatment centers, and 116 in school-based clinics. Mean age was 16 yrs, over 90% were sexually experienced, nearly 50% did not use condom with the last sex, less than 40% reported "current" birth control use, over 2/3 had sexual intercourse in past 3 months, many with multiple partners. Prevalence rates for CT and GC are summarized in the table. Conclusions: Non-invasive (urine) LCR/PCR tests allow for easy monitoring of selected STDs among adolescent women in high-risk settings. These findings may contribute to a sentinel surveillance system among high-risk populations and, in turn, may provide the rationale for the development of health care/intervention priorities at policy level.

Enterobacter cloacae bloodstream infections traced to contaminated human albumin

In August 1996, a patient in Kansas developed an Enterobacter cloacae bloodstream infection (BSI) shortly after receiving Albuminar, a brand of human albumin. Albuminar contamination was suspected. A case-control study of patients with primary gram-negative bacterial BSIs showed that patients with E. cloacae BSIs were significantly more likely than patients with non-E. cloacae gram-negative BSIs to have received Albuminar within 3 days of developing their BSIs (3 of 5 vs. 0 of 9; OR, undefined; P=.03). The E. cloacae isolate from the Kansas patient was found by pulsed-field gel electrophoresis to be identical to the isolate from the patient's Albuminar vial, to isolates from 2 previously unopened Albuminar vials, and to an isolate from a Wisconsin patient who had received Albuminar. A worldwide recall of approximately 116,000 Albuminar vials took place. This multistate outbreak was detected because of clinical astuteness and prompt reporting. Combined epidemiological and laboratory approaches are valuable when investigating potentially contaminated blood components and plasma derivatives.

An outbreak of gram-negative bacteremia in hemodialysis patients traced to hemodialysis machine waste drain ports

OBJECTIVE

To investigate an outbreak of gram-negative bacteremias at a hemodialysis center (December 1, 1996-January 31, 1997).

DESIGN

Retrospective cohort study. Reviewed infection control practices and maintenance and disinfection procedures for the water system and dialysis machines. Performed cultures of the water and dialysis machines, including the waste-handling option (WHO), a drain port designed to dispose of saline used to flush the dialyzer before patient use. Compared isolates by pulsed-field gel electrophoresis.

SETTING

A hemodialysis center in Maryland.

RESULTS

94 patients received dialysis on 27 machines; 10 (11%) of the patients had gram-negative bacteremias. Pathogens causing these infections were Enterobacter cloacae (n = 6), Pseudomonas aeruginosa (n = 4), and Escherichia coli (n = 2); two patients had polymicrobial bacteremia. Factors associated with development of gram-negative bacteremias were receiving dialysis via a central venous catheter (CVC) rather than via an arterio-venous shunt (all 10 infected patients had CVCs compared to 31 of 84 uninfected patients, relative risk [RR] undefined; P<.001) or dialysis on any of three particular dialysis machines (7 of 10 infected patients were exposed to the three machines compared to 20 of 84 uninfected patients, RR = 5.8; P = .005). E cloacae, P aeruginosa, or both organisms were grown from cultures obtained from several dialysis machines. WHO valves, which prevent backflow from the drain to dialysis bloodlines, were faulty in 8 (31%) of 26 machines, including 2 of 3 machines epidemiologically linked to case-patients. Pulsed-field gel electrophoresis patterns of available dialysis machine and patient E cloacae isolates were identical.

CONCLUSIONS

Our study suggests that WHO ports with incompetent valves and resultant backflow were a source of cross-contamination of dialysis bloodlines and patients' CVCs. Replacement of faulty WHO valves and enhanced disinfection of dialysis machines terminated the outbreak.

Total mandibular and lower lip reconstruction with a prefabricated osteocutaneous free flap

Large, complex bony defects can be a vexing problem for the reconstructive surgeon, especially when standard donor sites are not available or do not provide sufficient tissue. Using the concept of flap prefabrication, we demonstrated in a single patient that (1) iliac crest bone chips and bone morphogenic protein in an alloplastic mandibular tray can ossify in a heterotopic location and (2) neovascularization sufficient to support a large, custom-designed bone graft occurs within a convenient "carrier" flap. Ultimately, the fields of angiogenesis and osteogenesis research could significantly contribute to the ability of the plastic surgeon to construct the "ideal" composite prefabricated flap for complicated reconstruction.

Dietary isoflavones reduce plasma cholesterol and atherosclerosis in C57BL/6 mice but not LDL receptor-deficient mice

Susceptibility to atherosclerosis is determined by a combination of genetic and environmental factors, including diet. Consumption of diets rich in soy protein has been claimed to protect against the development of atherosclerosis. Potential mechanisms include cholesterol lowering, inhibition of lipoprotein oxidation and inhibition of cell proliferation by soy proteins or isoflavones, such as genistein, that are present in soy. This study was designed to determine whether soy isoflavones confer protection against atherosclerosis in mice and whether they reduce serum cholesterol levels and lipoprotein oxidation. C57BL/6 and LDL receptor-deficient (LDLr-null) mice were fed soy protein-based, high fat diets with isoflavones present (IF+, 20.85 g/100 g protein, 0.027 g/100 g genistein, 0.009 g/100 g daidzein) or diets from which isoflavones, and possibly other components, had been extracted (IF-, 20.0 g/100 g protein, 0.002 g/100 g genistein, 0.001 g/100 g daidzein). Because LDLr-null mice develop extensive atherosclerosis and hypercholesterolemia after minimal time on a high fat diet, they were fed the diets for 6 wk, whereas C57BL/6 mice were fed the diets for 10 wk. Plasma cholesterol levels did not differ between LDLr-null mice fed IF- and those fed IF+, but were 30% lower in C57BL/6 mice fed the IF+ diet than in those fed the IF- diet. Susceptibility of LDL to oxidative modification, measured as the lag phase of conjugated diene formation in LDLr-null mice, was not altered by isoflavone consumption. All LDLr-null mice developed atherosclerosis, and the presence or deficiency of dietary isoflavones did not influence atherosclerotic lesion area. In contrast, atherosclerotic lesion area was significantly reduced in C57BL/6 mice fed IF+ compared with those fed IF-. Thus, this study demonstrates that although the isoflavone-containing diet resulted in a reduction in cholesterol levels in C57BL/6 mice, it had no effect on cholesterol levels or on susceptibility of LDL to oxidative modification in LDLr-null mice. Further, dietary isoflavones did not protect against the development of atherosclerosis in LDLr-null mice but did decrease atherosclerosis in C57BL/6 mice. These findings suggest that soy isoflavones might lower cholesterol levels by increasing LDL receptor activity, and the reduction in cholesterol may offer some protection against atherosclerosis.

Alveolar ridge augmentation with bioactive glass ceramics: a histological study

A particulate BGC (bioactive glass ceramics), has been developed as a new bone graft biomaterial for alveolar ridge augmentation and has been evaluated by simulated animal models. Five beagle dogs were used in this investigation. Prior to augmentation the mandibular posterior teeth of the animals were extracted. Three months after the extractions, the porous BGC particles were packed into the subperiosteal tunnels in the ridges with a special syringe. The animals were killed at different time intervals and the specimens were examined by light microscopy, scanning electron microscopy (SEM), and X-ray energy dispersive analysis (EDAX), respectively. The results of this study indicate that the BGC particles are firmly combined with the adjacent hard and soft tissues by the bone bonding interface between the implants and the alveolar bone, and by the ingrowth of bone or fibrous connective tissue into the interspaces and the pores of the particles. The results have demonstrated that particulate BGC with pores is an excellent implant material for alveolar ridge augmentation because of its very good biocompatibility.