Effect of lactose standardization of milk using low-concentration factor ultrafiltration: Effect of reducing the lactose-to-casein ratio on the properties of milled-curd Cheddar cheese.

The pH of cheese is determined by the amount of lactose fermented and the buffering capacity of the cheese. The buffering capacity of cheese is largely determined by the protein contents of milk and cheese and the amount of insoluble calcium phosphate in the curd, which is related to the rate of acidification. The objective of this study was to standardize both the lactose and casein contents of milk to better control final pH and prevent the development of excessive acidity in Cheddar cheese. This approach involved the use of low-concentration factor ultrafiltration of milk to increase the casein content (∼5%), followed by the addition of water, ultrafiltration permeate, or both to the retentate to adjust the lactose content. We evaluated milks with 4 different lactose-to-casein ratios (L:CN): 1.8 (control milk), 1.4, 1.1, and 0.9. All cheesemilks had similar total casein (2.3%) and fat (3.4%) contents. These milks were used to make milled-curd Cheddar cheese, and we evaluated cheese composition, texture, functionality, and sensory properties over 9 mo of ripening. Cheeses made from milks with varying levels of L:CN had similar moisture, protein, fat, and salt contents, due to slight modifications during manufacture (i.e., cutting the gel at a smaller size than control) as well as control of acid development at critical steps (i.e., cutting the gel, whey drainage, salting). As expected, decreasing the L:CN led to cheeses with lower lactic acid, residual lactose, and insoluble Ca contents, as well as a substantial pH increase during cheese ripening in cheeses. The L:CN ratio had no significant effect on the levels of primary and secondary proteolysis. Texture profile analysis showed no significant differences in hardness values during ripening. Maximum loss tangent, an index of cheese meltability, was lower until 45 d for the L:CN 1.4 and 0.9 treatments, but after 45 d, all reduced L:CN cheeses had higher maximum loss tangent values than the control cheese (L:CN 1.8). Sensory analyses showed that cheeses made from milks with reduced L:CN contents had lower acidity, sourness, sulfury notes, and chewdown cohesiveness. Standardization of milk to a specific L:CN ratio, while maintaining a constant casein level in the milk, would allow Cheddar cheese manufacturers to have tighter control of pH and acidity.

Fluorocarbon Modified Low-Molecular-Weight Polyethylenimine for siRNA Delivery.

We report the synthesis and study of fluorocarbon (FC) modified polyethylenimine (PEI) for the purpose of siRNA delivery. Low-molecular-weight PEI (Mn = 600) was functionalized with fluorocarbon epoxides of varying length. All FC-modified samples with greater than 2.0 equiv of FC epoxide per PEI induced potent gene silencing in vitro. Compared to hydrocarbon (HC) analogues, the FC vectors showed greater general silencing efficacy, higher cell uptake, and reduced association with serum components. Collectively, the data suggest that modification of polyamines with FCs is a promising approach for the discovery of novel vectors for siRNA delivery.

Focused Library Approach to Discover Discrete Dipeptide Bolaamphiphiles for siRNA Delivery.

In this study, we report a new dipeptide functionalization strategy for developing new dendritic bolaamphiphile vectors for efficient siRNA transfection. A focused library of dipeptides was constructed using four amino acids: l-arginine, l-histidine, l-lysine, and l-tryptophan. The dipeptides were coupled to two dendritic bolaamphiphile scaffolds that we developed previously, allowing us to quickly access a focused library of discrete vectors with multivalent dendritic dipeptide functionalities. The resulting discrete bolaamphiphiles were screened for siRNA delivery in vitro in HEK-293 and HeLa cells. Bolaamphiphiles functionalized with dipeptides containing Lys or Arg and either His or Trp were the most effective for in vitro siRNA delivery. Necessary cationic charge to ensure efficient siRNA binding are provided by Arg and Lys residues, whereas endosomal escape is provided through pH responsive buffering of His or membrane interactions of Trp. The most effective vectors (F10 HR/RH) exhibited greater than 75% gene silencing in multiple cell lines and exhibited serum stability.

Evaluation of NaCl, pH, and lactic acid on the growth of Shiga toxin-producing Escherichia coli in a liquid Cheddar cheese extract.

A Cheddar cheese model system, Cheddar cheese extract, was used to examine how different levels of known microbial hurdles (NaCl, pH, and lactic acid) in Cheddar cheese contribute to inhibition of bacterial pathogens. This knowledge is critical to evaluate the safety of Cheddar varieties with altered compositions. The range of levels used covered the lowest and highest level of these factors present in low-sodium, low-fat, and traditional Cheddar cheeses. Four pathogens were examined in this model system at 11 °C for 6 wk, with the lowest levels of these inhibitory factors that would be encountered in these products. The 4 pathogens examined were Salmonella enterica, Staphylococcus aureus, Listeria monocytogenes, and Shiga toxin-producing Escherichia coli (STEC). None of these organisms were capable of growth under these conditions. The STEC exhibited the highest survival and hence was used to examine which of these inhibitory factors (NaCl, pH, and lactic acid) was primarily responsible for the observed inhibition. The STEC survival was examined in Cheddar cheese extract varying in NaCl (1.2 vs. 4.8%), lactic acid (2.7 vs. 4.3%), and pH (4.8 vs. 5.3) at 11 °C for 6 wk. The microbial hurdle found to have the greatest effect on STEC survival was pH. The interactions between pH and levels of protonated lactic acid and anionic lactic acid with STEC survival was also evaluated; only the concentration of protonated lactic acid was determined to have a significant effect on STEC survival. These results indicate that, of the pathogens examined, STEC is of the greatest concern in Cheddar varieties with altered compositions and that pH is the microbial hurdle primarily responsible for controlling STEC in these products.

Spectral Decomposition of the Flow and Characterization of the Sound Signals through Stenoses with Different Levels of Severity.

Treatments of atherosclerosis depend on the severity of the disease at the diagnosis time. Non-invasive diagnosis techniques, capable of detecting stenosis at early stages, are essential to reduce associated costs and mortality rates. We used computational fluid dynamics and acoustics analysis to extensively investigate the sound sources arising from high-turbulent fluctuating flow through stenosis. The frequency spectral analysis and proper orthogonal decomposition unveiled the frequency contents of the fluctuations for different severities and decomposed the flow into several frequency bandwidths. Results showed that high-intensity turbulent pressure fluctuations appeared inside the stenosis for severities above 70%, concentrated at plaque surface, and immediately in the post-stenotic region. Analysis of these fluctuations with the progression of the stenosis indicated that (a) there was a distinct break frequency for each severity level, ranging from 40 to 230 Hz, (b) acoustic spatial-frequency maps demonstrated the variation of the frequency content with respect to the distance from the stenosis, and (c) high-energy, high-frequency fluctuations existed inside the stenosis only for severe cases. This information can be essential for predicting the severity level of progressive stenosis, comprehending the nature of the sound sources, and determining the location of the stenosis with respect to the point of measurements.

Spectral Decomposition and Sound Source Localization of Highly Disturbed Flow through a Severe Arterial Stenosis.

For the early detection of atherosclerosis, it is imperative to explore the capabilities of new, effective noninvasive diagnosis techniques to significantly reduce the associated treatment costs and mortality rates. In this study, a multifaceted comprehensive approach involving advanced computational fluid dynamics combined with signal processing techniques was exploited to investigate the highly turbulent fluctuating flow through arterial stenosis. The focus was on localizing high-energy mechano-acoustic source potential to transmit to the epidermal surface. The flow analysis results showed the existence of turbulent pressure fluctuations inside the stenosis and in the post-stenotic region. After analyzing the turbulent kinetic energy and pressure fluctuations on the flow centerline and the vessel wall, the point of maximum excitation in the flow was observed around two diameters downstream of the stenosis within the fluctuating zone. It was also found that the concentration of pressure fluctuation closer to the wall was higher inside the stenosis compared to the post-stenotic region. Additionally, the visualization of the most energetic proper orthogonal decomposition (POD) mode and spectral decomposition of the flow indicated that the break frequencies ranged from 80 to 220 Hz and were correlated to the eddies generated within these regions.

HIV risk behavior self-report reliability at different recall periods.

Few studies have investigated the optimal length of recall period for self-report of sex and drug-use behaviors. This meta-analysis of 28 studies examined the test-retest reliability of three commonly used recall periods: 1, 3, and 6 months. All three recall periods demonstrated acceptable test-retest reliability, with the exception of recall of needle sharing behaviors and 6-months recall of some sex behaviors. For most sex behaviors, a recall period of 3 months was found to produce the most reliable data; however, 6 months was best for recalling number of sex partners. Overall, shorter periods were found to be more reliable for recall of drug-use behaviors, though the most reliable length of recall period varied for different types of drugs. Implications of the findings and future directions for research are discussed.

Drug users' test-retest reliability of self-reported alcohol use on the risk behavior assessment.

Using data collected from 218 street drug users in 11 cities in the United States, we examined the test-retest reliability of the alcohol-related items on the Risk Behavioral Assessment (RBA; National Institute on Drug Abuse, 1993), an instrument commonly used in drug abuse research. With a 48-hr retest interval, findings indicated excellent to good reliability for the following variables: age of first use, ever used alcohol, and days used alcohol in last 30 days. Items with fair to poor reliability were number of occasions used alcohol in last 30 days without injecting and number of times used alcohol immediately before or during sex. These findings suggest that self-report items on alcohol use from the RBA are generally reliable, particularly items that ask for more general, rather than specific, information.

Reduction of Sodium and Fat Levels in Natural and Processed Cheeses: Scientific and Technological Aspects.

The various types of cheese are nutrient-dense foods that are good sources of calcium, phosphorus, and protein. They are also important ingredients in many highly consumed foods such as pizza, cheeseburgers, and sauces. However, they are also perceived as being high in fat and sodium. Consumers have indicated that they would like to continue utilizing cheese in their diet but would prefer to have lower-fat and lower-sodium products. Fat and salt are important elements in the flavor, texture, food safety, and overall acceptability of cheese. Alternatives to fat and salt are being investigated but have not been found to be acceptable, especially in those products that meet the FDA's definition of low-fat and/or low-sodium. This review is primarily a report on the current status of research to develop desirable cheeses with low-fat and/or low-sodium, their regulatory and labeling status, consumer acceptability, and challenges for further efforts.

Health implications of sex trading characteristics in Long Beach, California, USA.

This study examined the comparative health risk behaviors of women who (a) traded sex for money, (b) traded sex for drugs, (c) traded sex for both drugs and money, or (d) did not trade sex. Self-report data were collected from 2369 women who received services through HIV and sexually transmitted infection (STI) testing programs and a subset were tested for HIV, hepatitis B, hepatitis C, and syphilis. Results revealed those women who traded sex only for money used condoms, were tested for HIV, and received the HIV test results more often than the other women. Women who traded sex for both drugs and money reported a significantly higher prevalence of gonorrhea, hepatitis B, and syphilis; were more likely to test positive for hepatitis B, syphilis, and HIV; engaged more often in sex acts without condoms; and were incarcerated for significantly more days. Based on these findings, the targets with greatest potential for STI prevention interventions are female sex workers who trade sex for both drugs and money.

Adaptations to health care barriers as reported by rural and urban providers.

Barriers to ethical and effective health care in rural communities have been well-documented; however, less is known about strategies rural providers use to overcome such barriers. This study compared adaptations by rural and urban health care providers. Physical and behavioral health care providers were randomly selected from licensure lists for eight groups to complete a survey; 1,546 (52%) responded. Replies indicated that health care providers from small rural and rural communities were more likely to integrate community resources, individualize treatment recommendations, safeguard client confidentiality, seek out additional expertise, and adjust treatment styles than were providers from small urban and urban communities. Behavioral health care providers were more likely than physical health care providers to integrate community resources, individualize treatment recommendations, safeguard client confidentiality, and adjust their treatment styles; physical health care providers were more likely than behavioral health care providers to make attempts or have options to seek out additional expertise.

When providers and patients come from different backgrounds: perceived value of additional training on ethical care practices.

Fostering the therapeutic alliance, safeguarding confidentiality, gaining informed consent, and enhancing treatment adherence are critical aspects of patient care. We examined whether multidisciplinary health care providers perceive additional training on these areas as helpful in their work with patients from different ethnic backgrounds than the provider. Data are drawn from a National Institute on Drug Abuse-funded survey of 1555 providers in 8 disciplines in New Mexico and Alaska. Clinicians viewed additional training as moderately helpful for ensuring treatment adherence, establishing the therapeutic alliance, safeguarding confidentiality, and engaging in informed consent processes, in that order. Women were more receptive than men to additional training. Modest differences were detected between behavioral and physical health providers and between minority and majority providers. Implications of providers' only modest interest in such training are discussed.

Receiver operating characteristics for the brief symptom inventory depression, paranoid ideation, and psychoticism scales in a large sample of clinical inpatients.

A commonly used screening tool for psychopathology, the Brief Symptom Inventory, provides normative data for assessing current mental functioning across multiple domains. Using data from 654 psychiatric inpatients, receiver operating characteristic (ROC) analyses were conducted for three scales, Depression, Paranoid Ideation, and Psychoticism. t ratios identified significant group differences on the Depression scale between patients diagnosed with or without depression but no differences on the Paranoid Ideation and Psychoticism scales between patients diagnosed with or without schizophrenia. Area under the curve for Depression was .65, indicating that the scale improved diagnostic prediction somewhat beyond chance; for Paranoid Ideation, the area was .52 and for Psychoticism, the area was .53, indicating that these two scales did not significantly improve diagnostic prediction beyond chance.

Dendritic peptide bolaamphiphiles for siRNA delivery to primary adipocytes.

Obesity is a major risk factor for diabetes, heart disease and other health problems. Adipose tissue plays a central role in the development of obesity and obesity-associated diseases. Gene therapy targeting adipose tissue may provide a promising strategy for obesity treatment. However, nucleic acid delivery to adipose tissue or even cultured adipocytes is challenging due to low delivery efficacy and high toxicity of the current cationic lipid based delivery systems, or monoamphiphiles. Herein, we report using dendritic peptide bolaamphiphiles (bolas) to deliver siRNA to primary adipocytes and hepatocytes. The bola consists of two l-Lysine dendrons connected to a fluorocarbon core through disulfide linkages. The Lysine dendrons are functionalized with l-histidine and l-tryptophan to promote endosomal escape and cellular uptake. The bola exhibited over 70% knockdown of GAPDH gene in both primary adipocytes and hepatocytes. Importantly, different from Lipofectamine that significantly reduced genes involved in lipolysis, lipogenesis, fatty acid oxidation and ketogenesis, the bolas had little to no effect on these genes. These results demonstrate the bola as a promising new vector for clinical and experimental applications for delivery of siRNA to metabolic organs.

Test-retest reliability of self-reported drug treatment variables.

We conducted two studies to assess the test-retest reliability of drug treatment questions in the Risk Behavior Assessment (RBA) and Risk Behavior Follow-Up Assessment (RBFA). In Study 1, 218 active drug users participated in an RBA 48-hour test-retest reliability assessment; in Study 2, 257 active drug users participated in an RBFA 48-hour test-retest reliability assessment. Results revealed acceptable reliability for the main drug treatment question in both the RBA (.85) and RBFA (.85): "Have you ever in your lifetime been in a drug treatment or detoxification center?" Other more specific drug treatment questions yielded mixed results. Twenty-four of the 35 RBA and RBFA treatment variables (68.6%) that could be calculated displayed acceptable test-retest reliability coefficients. Test-retest reliability coefficients for the RBFA continuous variables could not be calculated owing to a lack of participants in drug treatment during the previous 6 months. Future research establishing greater delineation of this problem may aid in the construction of assessment instruments.

Psychiatric symptomatology among individuals in alcohol detoxification treatment.

The coexistence of psychiatric symptomatology among individuals receiving longer-term treatment for alcohol use disorders has been well-established; however, less is known about comorbidity among individuals receiving alcohol detoxification. Using the Brief Symptom Inventory [BSI; Derogatis, L. R. (1992). BSI: Administration, scoring, and procedures manual--II. Towson, MD: Clinical Psychometric Research], we compared psychiatric symptomatology among 815 individuals receiving short-term detoxification services with normative data from non-patients, psychiatric patients, and out-of-treatment individuals using street drugs. Findings revealed that individuals in the current sample reported a wide range of psychiatric symptoms with over 80% meeting BSI criteria for diagnosable mental illness. These BSI scores were significantly more severe than those reported by out-of-treatment individuals using street drugs and most closely resembled BSI scores reported for adult psychiatric inpatients. Findings suggest that routine screening for severe mental health symptoms appears warranted in detoxification units. Such screening would greatly increase the chance that coexistence of substance use and other psychiatric disorders would be properly addressed in ongoing treatment.

Ethical disparities: challenges encountered by multidisciplinary providers in fulfilling ethical standards in the care of rural and minority people.

CONTEXT: Health care disparities are well documented for people living in rural areas and for people who are members of ethnic minorities. PURPOSE: Our goal was to determine whether providers report greater difficulty in providing care for rural than urban residents and for ethnic minorities than patients/clients in general in 4 practice areas of ethical relevance: attaining treatment adherence, assuring confidentiality, establishing therapeutic alliance, and engaging in informed consent processes. METHODS: We received survey responses from 1,558 multidisciplinary medical and behavioral providers across rural and non-rural areas of New Mexico and Alaska in 2004 to assess a wide range of issues in providing health care. FINDINGS: Providers reported some difficulties in fulfilling various ethical practices for all types of patients, but not more difficulty when caring for minority compared to nonminority patients/clients. However, they do report more frequent additional problems related to the practice issues of treatment adherence, therapeutic alliance, informed consent, and confidentiality with minority patients than others. Difficulties and more frequent additional problems are greater for providers in rural than in non-rural areas. Results generalize across both Alaska and New Mexico with few differences. CONCLUSIONS: We obtained evidence for disparity in care for patients/ clients who were minority group members, and clear evidence of disparity for people residing in rural compared to non-rural areas of 2 states with large rural areas.

Measuring the Frequency Occurrence of Handwriting and Handprinting Characteristics.

The premise of this study was to take a valid population sampling of handwriting and handprinting and assess how many times each of the predetermined characteristic is found in the samples. Approximately 1500 handwriting specimens were collected from across the United States and pared to obtain a representative sample of the U.S. adult population according to selected demographics based on age, sex, ethnicity, handedness, education level, and location of lower-grade school education. This study has been able to support a quantitative assessment of extrinsic and intrinsic effects in handwriting and handprinting for the six subgroups. Additional results include analyses of the interdependence of characteristics. This study found that 98.55% of handprinted characteristics and 97.39% of cursive characteristics had an independence correlation of under 0.2. The conclusions support use of the product rule in general, but with noted caveats. Finally, this study provides frequency occurrence proportions for 776 handwriting and handprinting characteristics.

A Head-to-Head Comparative Phase II Study of Standard Urine Culture and Sensitivity Versus DNA Next-generation Sequencing Testing for Urinary Tract Infections.

Many studies have discussed clinical practice guidelines for the treatment of cystitis and pyelonephritis. Treatment of uncomplicated urinary tract infections (UTIs) can be based on empiric antibiotic therapy. For complicated or recurrent UTIs, therapy can be based on laboratory-controlled culture and sensitivity (C&S) reports. The diagnosis of UTI by clinical criteria alone has an error rate of up to 33%. In addition, positive laboratory culture results do not always indicate a diagnosis of UTI. Comparison of urine in a conventional culture model versus DNA next-generation sequencing (NGS) to accurately identify and provide information on resistance factors (mobile genetic elements) is warranted. Our study was a head-to-head comparative phase II study of standard urine C&S versus DNA NGS testing for the diagnosis and treatment efficacy in patients with symptoms of acute cystitis based on short-term outcomes.

Physical properties and surface activity of surfactant-like membranes containing the cationic and hydrophobic peptide KL4.

Surfactant-like membranes containing the 21-residue peptide KLLLLKLLLLKLLLLKLLLLK (KL4), have been clinically tested as a therapeutic agent for respiratory distress syndrome in premature infants. The aims of this study were to investigate the interactions between the KL4 peptide and lipid bilayers, and the role of both the lipid composition and KL4 structure on the surface adsorption activity of KL4-containing membranes. We used bilayers of three-component systems [1,2-dipalmitoyl-phosphatidylcholine/1-palmitoyl-2-oleoyl-phosphatidylglycerol/palmitic acid (DPPC/POPG/PA) and DPPC/1-palmitoyl-2-oleoyl-phosphatidylcholine (POPC)/PA] and binary lipid mixtures of DPPC/POPG and DPPC/PA to examine the specific interaction of KL4 with POPG and PA. We found that, at low peptide concentrations, KL4 adopted a predominantly alpha-helical secondary structure in POPG- or POPC-containing membranes, and a beta-sheet structure in DPPC/PA vesicles. As the concentration of the peptide increased, KL4 interconverted to a beta-sheet structure in DPPC/POPG/PA or DPPC/POPC/PA vesicles. Ca2+ favored alpha<-->beta interconversion. This conformational flexibility of KL4 did not influence the surface adsorption activity of KL4-containing vesicles. KL4 showed a concentration-dependent ordering effect on POPG- and POPC-containing membranes, which could be linked to its surface activity. In addition, we found that the physical state of the membrane had a critical role in the surface adsorption process. Our results indicate that the most rapid surface adsorption takes place with vesicles showing well-defined solid/fluid phase co-existence at temperatures below their gel to fluid phase transition temperature, such as those of DPPC/POPG/PA and DPPC/POPC/PA. In contrast, more fluid (DPPC/POPG) or excessively rigid (DPPC/PA) KL4-containing membranes fail in their ability to adsorb rapidly onto and spread at the air-water interface.