Use Of PPD Research Articles

Quantification of p-Phenylenediamine in Hair Dyes and Health Risk Implications in the UAE: Describing Discordances Between Regulations and Real-Life Practices.

p-Phenylenediamine (PPD) has been used over the past five decadesas a primary precursor in the production of oxidative hair dyes. Numerous health dangers are associated with the short- and long-term use of PPD, raising concerns about its safety. For instance, mounting data suggests that PPD is linked to dermatitis and allergy cases. To quantify the PPD content in hair dyes by measuring the PPD concentration after mixing the ingredients of commercial hair dyes. A total of 290 permanent hair dyes were tested. RP-HPLC-DAD analysis was performed to determine and quantify the PPD content. The estimated mean of the PPD limit was 0.89 (95% CI [0.81-0.96]). Of the 290 tested hair dyes, 7.2% (n = 21) exceeded the recommended PPD concentration after mixing. Significantly more hair dyes manufactured in India and China had a PPD content exceeding 2% after mixing compared to dyes from other regions (P = 0.001). Moreover, hair dyes manufactured in India and the UAE were more likely to have incomplete descriptions of the conditions of use and warnings on the label (P = 0.002). The effectiveness of the current regulations relevant to these products should be reevaluated. Moreover, through the use of good manufacturing procedures (GMPs), research, and the reporting of adverse reactions, hair dyes should be subjected to better control and monitoring in terms oftheir safety and quality.

A PD-L1 Antibody-Conjugated PAMAM Dendrimer Nanosystem for Simultaneously Inhibiting Glycolysis and Promoting Immune Response in Fighting Breast Cancer.

Breast cancer is the most frequent malignancy affecting women, yet current therapeutic strategies remain ineffective for patients with late-stage or metastatic disease. Here an effective strategy is reported for treating metastatic breast cancer. Specifically, a self-assembling dendrimer nanosystem decorated with an antibody against programmed cell death ligand 1 (PD-L1) is established for delivering a small interfering RNA (siRNA) to target 3-phosphoinositide-dependent protein kinase-1 (PDK1), a kinase involved in cancer metabolism and metastasis. This nanosystem, named PPD, is designed to target PD-L1 for cancer-specific delivery of the siRNA to inhibit PDK1 and modulate cancer metabolism while promoting programmed cell death 1 (PD-1)/PD-L1 pathway-based immunotherapy. Indeed, PPD effectively generates simultaneous inhibition of PDK1-induced glycolysis and the PD-1/PD-L1 pathway-related immune response, leading to potent inhibition of tumor growth and metastasis without any notable toxicity in tumor-bearing mouse models. Collectively, these results highlight the potential use of PPD as an effective and safe tumor-targeting therapy for breast cancer. This study constitutes a successful proof of principle exploiting the intrinsic features of the tumor microenvironment and metabolism alongside a unique self-assembling dendrimer platform to achieve specific tumor targeting and siRNA-based gene silencing in combined and precision cancer therapy.

COVID-19: What happened to the healthcare workers of a research and teaching hospital in Milan, Italy?

The paper wants to present the data of infection of the Health Care Workers of a research and teaching hospital in Milan, Italy. The majority (2554, 55.9%) of 4572 HCWs were tested for SARS-CoV-2 and 8.8% were found positive. Most of the tested workers were women, but we found higher relative frequency of positivity for men, even after adjustment for age, working area, and occupation. The higher frequency of positive tests in the medicine area is probably explained by the higher concentration in that area of COVID-19 patients. Conversely, the low frequency of positive HCWs in intensive care units is probably explained by the diffuse and continuous use of PPD. Our results show that HCWs in a research and teaching hospital in the most hit Region in Italy had a similar pattern of infection as all other HCWs all over the world. The problem of SARS-CoV-2 infections among the hospital personnel HCWs should remind us the concerns about hospital acquired infections both for patients and HCWs. (www.actabiomedica.it)

Evaluation of in vitro testing strategies for hazard assessment of the skin sensitization potential of "real-life" mixtures: The case of henna-based hair-colouring products containing p-phenylenediamine.

Allergic contact dermatitis caused by henna-based hair-colouring products has been associated with adulteration of henna with p-phenylenediamine (PPD). To develop a testing approach based on in vitro techniques that address key events within the skin sensitization adverse outcome pathway in order to evaluate the allergenic potential of hair-colouring products. The following in vitro assays were used to test the sensitizing capacity of hair dye ingredients: the micro-direct peptide reactivity assay (mDPRA); the HaCaT keratinocyte-associated interleukin (IL)-18 assay; the U937 cell line activation test (U-SENS)/IL-8 levels; the blood monocyte-derived dendritic cell test; and genomic allergen rapid detection (GARD skin). Those techniques with better human concordance were selected to evaluate the allergenic potential of 10 hair-colouring products. In contrast to the information on the label, chromatographic analyses identified PPD in all products. The main henna biomarker, lawsone, was not detected in one of the 10 products. Among the techniques evaluated by testing hair dye ingredients, the mDPRA, the IL-18 assay, GARD skin and the U-SENS correlated better with human classification (concordances of 91.7%-100%) and were superior to the animal testing (concordance of 78.5%). Thus, these assays were used to evaluate hair-colouring products, which were classified as skin sensitizers by the use of different two-of-three approaches. Our findings highlight the toxicological consequences of, and risks associated with, the undisclosed use of PPD in henna-based "natural" "real-life" products.

The use of a star-shaped trifunctional acyl chloride for the preparation of polyamide thin film composite membranes

A star-shaped trifunctional acyl chloride bearing ether linkages was synthesized as an alternative to the commonly used trimesoyl chloride (TMC) in the preparation of polyamide thin film composite membranes (TFC). Although this star-shaped acyl chloride has the same functionality as TMC, it is larger in size and its acyl chloride groups are less reactive due to the electron donating ether linkages. In this work, we prepared TFC membranes by the interfacial polymerization of both this star-shaped acyl chloride and TMC with either one of the two structural isomers: m-phenylenediamine (MPD) or p-phenylenediamine (PPD). No strong effect was observed of the substitution pattern of the aromatic diamine on the membrane formation with TMC, due to the high reactivity of the acyl chloride groups of TMC. In contrast, the use of this star-shaped acyl chloride results in significant differences in the properties of the formed TFC membrane depending on the use of MPD or PPD. Where TMC-MPD membranes are well-known for their excellent retention, we could not obtain defect-free membranes prepared from MPD and this star-shaped triacyl chloride (Rrosebengal<77%). The use of PPD instead of MPD, however, did result in defect-free membranes (Rrosebengal>97%) with an acceptable clean water permeance (2.5 L m−2 h−1 bar−1).

Evaluation of concordance between labelling and content of 52 hair dye products: overview of the market of oxidative hair dye

Hair dyes contain strong allergens and are widely available. Correct labelling is a necessity in order to provide information about the contents. To compare the labelling and content of hair dyes. In total, 52 hair dyes, from 11 different countries, were bought over the counter. High-pressure liquid chromatography was used for the analysis of p-phenylenediamine (PPD), toluene-2,5-diamine (2,5-TDA), and three oxidation products of PPD. There was good agreement between labelling and content, although seven of the 52 products (13.5%) studied were incorrectly labelled. There were differences in the geographical use of PPD and 2,5-TDA; 2,5-TDA was more common in European products, while PPD was more common in products purchased outside Europe and was present in higher concentrations. All dyes purchased in Europe contained PPD and 2,5-TDA at levels within the limits defined by European legislation, however, levels were higher in some products purchased outside Europe. Only a small group of hair dyes sold in Europe were mislabelled. Further improvement in labelling, by providing the concentration of chemicals, may facilitate products to be purchased both locally and within the global market, when travelling or on the internet.

ESTABLISHMENT OF AN INTERVENTION HEALTH EDUCATION PROGRAM FOR ENVIRONMENTAL, HEALTH PROMOTION OF ALUMINUM WORKERS

Even though aluminum is not considered to be a heavy metal like lead, it can be toxic in excessive amounts and even in small amounts if it is deposited in the brain. Many of the symptoms of aluminum toxicity mimic those of Alzheimer’s disease and osteoporosis. Colic, rickets, gastrointestinal problems, interference with the metabolism of calcium, extreme nervousness, anemia, headaches, decreased liver and kidney function, memory loss, speech problems, softening of the bones, and aching muscles can all be caused by aluminum toxicity. This study included 40 workers in an aluminum factory in 6th October District in Egypt with mean aluminum concentration in the different departments in the factory was within permissible exposure level PEL. Data were collected through a previously prepared questionnaire which consists of three parts. The first part was concerned with demographic data such as age and nationality. The second part was concerned with occupational data such as working hours, working years, smoking, and diseases. The third part concerned with knowledge, attitude and practice about aluminum hazards. The studied workers have reported the exposure to aluminum inside workplace during polishing and during smelting (85 % and 82.5 % respectively). However, majority of workers also reported an extra workplace exposure to aluminum with most of them in form of using alum. Utensils followed by use of food additives containing aluminum (72.5 % and 70 % respectively). By implementing the intervention study through the comprehensive health education program to workers in the factory, there was a statistically significant reduction in the mean serum aluminum before and after intervention (13.95 and 13.75 up/dl respectively) (P<0.01). Also, the intervention study has improved significantly the knowledge of workers toward the use of PPD by 45.5 % (P<0.01). At the same time, the knowledge of workers toward the exposure to the extra work sources of aluminum was significantly improved as regards aluminum Contained medications and aluminum Containing deodorants by 50 % and 62.5 % respectively (P<0.01). Finally Special safety precautions and educational programs are also needed to limit the aluminum exposure in this industrial group.

Effect of diphenyliodonium hexafluorophosphate on the physical and chemical properties of ethanolic solvated resins containing camphorquinone and 1-phenyl-1,2-propanedione sensitizers as initiators

ObjectivesTo evaluate the effects of the diphenyliodonium hexafluorophosphate (DPI) on the physical and mechanical properties of solvated dental adhesive resins containing camphorquinone (CQ) and/or 1-phenyl-1,2-propanedione (PPD) as initiators. MethodsModel solvated resins containing bisphenol glycidyl methacrylate (BisGMA); triethyleneglycol dimethacrylate (TEGDMA); 1,3-glycerol dimethacrylate (GDMA); 2-hydroxyethyl methacrylate (HEMA); dimethylaminoethyl amine benzoate (EDAB) and ethanol were prepared. The resins were divided in 24 test groups according to the incorporated initiator systems (CQ-0.5 or 1mol%; PPD-0.5 or 1mol%; CQ+PPD-0.5 or 1mol%) as well the presence of DPI (0, 0.5 or 1mol%). Degree of conversion (using Fourier-transformed near infra-red spectroscopy), flexural strength and modulus by three point bending, cohesive strength and water sorption and solubility were measured. Data were statistically analyzed by one and two way ANOVA and Tukey's test (α=0.05). ResultsDPI increased the degree of conversion of all materials tested. Camphorquinone promoted higher degree of conversion than resins containing only PPD or CQ+PPD. Generally, the resins containing PPD+CQ with DPI presented higher flexural strength and modulus, cohesive strength, as well lower water sorption and solubility. SignificanceThe use of PPD combined with CQ can increase the physical properties of the solvated resins. DPI improved the monomer conversion of all experimental materials and can positively modulate most of the physical properties of the solvated resins.

Is the Use of PPD in Black Henna Tattoo Criminal or Remiss?

Para-phenylenediamine (PPD) is a known strong sensitizer and allergen. It has been directly associatedwith severe allergic contact dermatitis reactions and systemic toxicities. While PPD is permitted inhair-dye with restriction, it is prohibited for direct use on skin. Unfortunately, skin application continuesthrough temporary tattoos with black henna dyes, because these products are unregulated by the US Foodand Drug Administration. Policy change, and parent and child-oriented educational campaigns are necessaryto build knowledge of this serious issue.

Is the Use of PPD in Black Henna Tattoo Criminal or Remiss?

Para-phenylenediamine (PPD) is a known strong sensitizer and allergen. It has been directly associatedwith severe allergic contact dermatitis reactions and systemic toxicities. While PPD is permitted inhair-dye with restriction, it is prohibited for direct use on skin. Unfortunately, skin application continuesthrough temporary tattoos with black henna dyes, because these products are unregulated by the US Foodand Drug Administration. Policy change, and parent and child-oriented educational campaigns are necessaryto build knowledge of this serious issue.

Enhanced oral absorption of 20(S)-protopanaxadiol by self-assembled liquid crystalline nanoparticles containing piperine: in vitro and in vivo studies

Background20(S)-protopanaxadiol (PPD), similar to several other anticancer agents, has low oral absorption and is extensively metabolized. These factors limit the use of PPD for treatment of human diseases.MethodsIn this study, we used cubic nanoparticles containing piperine to improve the oral bioavailability of PPD and to enhance its absorption and inhibit its metabolism. Cubic nanoparticles loaded with PPD and piperine were prepared by fragmentation of glyceryl monoolein (GMO)/poloxamer 407 bulk cubic gel and verified using transmission electron microscopy and differential scanning calorimetry. We evaluated the in vitro release of PPD from these nanoparticles and its absorption across the Caco-2 cell monolayer model, and subsequently, we examined the bioavailability and metabolism of PPD and its nanoparticles in vivo.ResultsThe in vitro release of PPD from these nanoparticles was less than 5% at 12 hours. PPD-cubosome and PPD-cubosome loaded with piperine (molar ratio PPD/piperine, 1:3) increased the apical to basolateral permeability values of PPD across the Caco-2 cell monolayer from 53% to 64%, respectively. In addition, the results of a pharmacokinetic study in rats showed that the relative bioavailabilities of PPD-cubosome [area under concentration–time curve (AUC)0–∞] and PPD-cubosome containing piperine (AUC0–∞) compared to that of raw PPD (AUC0–∞) were 166% and 248%, respectively.ConclusionThe increased bioavailability of PPD-cubosome loaded with piperine is due to an increase in absorption and inhibition of metabolism of PPD by cubic nanoparticles containing piperine rather than because of improved release of PPD. The cubic nanoparticles containing piperine may be a promising oral carrier for anticancer drugs with poor oral absorption and that undergo extensive metabolism by cytochrome P450.

Thermally treated copoly(ether-imide)s made from bpda and alifatic plus aromatic diamines. GAS separation properties with different aromatic diamimes

A set of copoly(ether-imide)s, formed by the reaction between an aromatic dianhydride (BPDA), a polyoxyalkyleneamine (poly(ethylene oxide) diamino terminated) (PEO-2000) and various aromatic diamines (PPD, BNZ, and ODA) under different thermal treatments, has been obtained and characterized. The existence of phase segregation in these copolymers has been confirmed by SAXS. It has also been proved that aromatic diamines having a hinge group, such as ODA, produce bigger segregated domains while short and rigid aromatic diamines give higher percentages of phase segregation. A direct relationship between gas permeability and percentage, and size of the domains, of the segregated phase has been obtained. Also, higher or similar selectivities have been observed as a function of the thermal treatment. In such way, the use of high temperatures during the thermal treatment, responsible of the improvement of the phase segregation, enhances the gas properties, producing materials with permeability/selectivity values close to the Robeson limit. In the case of the CH 4/N 2 pair an interesting reverse selectivity has been observed probably due both to a specific interaction of the gas with the polymer and to an increase in the solubility of CH 4 in the soft segregated portions of the copolymer. The use of PPD as comonomer provides more phase segregation while the use of ODA gives bigger segregated domains. In terms of permselectivity the performances, for all the pairs of gases studied, follow the PPD > BNZ > ODA sequence when relatively low treatment temperatures are used while quite similar results for BNZ and ODA were observed when higher treatment temperatures are employed. This seems to indicate that the domains size is a key factor in the gas separation properties with a certain influence of the percentage of segregation. An adequate balance of short length with limited rigidity of the aromatic part should improve the properties of this kind of materials.

Effect of co-initiator ratio on the polymer properties of experimental resin composites formulated with camphorquinone and phenyl-propanedione

Objectives To evaluate the effect of amine ratio (ethyl 4-dimethylaminobenzoate, EDMAB) on the maximum rate of polymerization ( R p max ), degree of conversion (DC), Knoop hardness (KH), water sorption (Wsp), water solubility (Wsl) and color changes (Δ E) over time of resin composites formulated with the photoinitiators camphorquinone (CQ), phenylpropanedione (PPD) and CQ-PPD in combination. Materials and methods Experimental resin composites were made with photoinitiator:amine ratios of 2:1, 1:1, 1:1.5 and 1:2 by weight. R p max was evaluated with differential scanning calorimetry (DSC), DC with DSC and Fourier transformed infrared (FTIR) spectroscopy, KH with Knoop indentation, Wsp and Wsl adapted from ISO 4049; and color with a chromameter. The results were analyzed with two-way ANOVA/Tukey’s multiple comparison test ( p < 0.05). Results The higher the amine ratio in the composite, the higher was DC, R p max , and KH, and the lower was Wsl, regardless of the photoinitiator type. The use of PPD alone resulted in poorer properties than CQ and CQ-PPD. Many factors seem to affect the color changes and the b-axis data revealed that the higher the amine ratio, the higher was the + b value (yellowing) for CQ and CQ-PPD formulations. Conclusions Higher amine ratios led to improved polymer properties, but also produced more yellowing in resin composites with CQ and CQ-PPD. The use of PPD alone was not advantageous for producing good final properties when compared to CQ and CQ-PPD.

Influence of photoinitiator type on the rate of polymerization, degree of conversion, hardness and yellowing of dental resin composites

Objectives To evaluate the degree of conversion (DC), maximum rate of polymerization ( R p max ), Knoop hardness (KHN) and yellowing ( b-value) of resin composites formulated with phenylpropanedione (PPD), camphorquinone (CQ), or CQ/PPD at different concentrations. The hypotheses tested were (i) PPD or CQ/PPD would produce less R p max and yellowing than CQ alone without affecting DC and KHN, and (ii) R p max , DC, and KHN would be directly related to the absorbed power density (PD abs). Methods CQ/amine, PPD/amine and CQ/PPD/amine were used at low, intermediate and high concentrations in experimental composites. Photoinitiator absorption and halogen-light emission were measured using a spectrophotometer, R p with differential scanning calorimetry (DSC), DC with DSC and FTIR, KHN with Knoop indentation; and color with a chromameter. The results were analyzed with two-way analysis of variance (ANOVA)/Student–Newman–Keul's test ( p < 0.05). Correlation tests were carried out between PD abs and each of DC, R p max and KHN. Results The PD abs increased with photoinitiator concentration and PPD samples had the lowest values. In general, maximum DC was comparable at intermediate concentration, while R p max and KHN required higher concentrations. DC was similar for all photoinitiators, but R p max was lower with PPD and CQ/PPD. PPD produced the lowest KHN. Yellowing increased with photoinitiator concentration. PPD did not reduce yellowing at intermediate and/or high concentrations, compared to CQ-formulations. PD abs showed significant correlations with DC, R p max and KHN. Conclusion PPD or CQ/PPD reduced R p max in experimental composites without affecting the DC. The use of PPD did not reduce yellowing, but reduced KHN. DC, R p max and KHN were dependent on PD abs.

The role of flow cytometry in the interferon-γ-based diagnosis of active tuberculosis and its coinfection with HIV-1-A technically oriented review

TB remains uncontrolled. In resource-rich countries, only approximately 60% of diagnoses are confirmed by culture. The number is lower in resource-poor environments. Huge scope therefore exists for alternative diagnostic strategies. Counting antigen-specific lymphocytes by virtue of cytokine production following 8-16 h stimulation with tuberculosis antigens is currently the strategy of choice. Several methods exist, including ELISA, ELISpots, and flow cytometry. Although it is clear that blood samples stimulated by ESAT-6 and CFP-10 antigens discriminate between TB infection and BCG vaccination, it is flow-cytometry that seems to be able to distinguish active TB disease from mere TB exposure. Of the various flow-protocols including four-color tests (CD45-CD3-CD4-IFNgamma), three-color tests (CD3-CD4-IFNgamma) and two-color tests (CD4-IFNgamma), even the simplest is performing well, provided that the results are expressed as percentage of IFN-gamma+ cells per CD4+ lymphocytes (%IFNgamma/CD4+). Studies using broncho-alveloar lavage (BAL) and Induced-Sputum (ISp) show that TB-specific CD4+IFN-gamma+ T cells accumulate in the lung in pulmonary and extra-pulmonary TB at frequencies >5-20-fold more frequent than in blood. This pulmonary homing is absent following BCG immunization. The use of PPD to stimulate CD4+IFN-gamma+ cells in the lung in active TB leads to >3-12-fold greater responses than seen with CFP-10 or ESAT-6, and any interference from BCG vaccination is absent. This method is unaffected by HIV coinfection, which has always been the problem for other immune-based diagnostics. Further, lung-based samples provide material for rapid tests of both the IFN-gamma assay and bacteriology, and importantly, these tests are amenable for future simplification with automated fluorescence-image cytometers.Another development of the multiparameter analytical power of flow-cytometry is to use markers for "lung-seeking" populations of CD4+ T cells in blood, obviating lung sampling. In active TB, but not in BCG vaccinees, TB-specific memory CD4+ T cells can be found in blood that are dominantly CD27-negative and probably lung seeking and can be diagnostically useful.

529. Development of Novel Systemic Gene Delivery System for Cancer Therapy with Tumor-Specifically Cleavable PEG-Lipid

Top of pageAbstract [Purpose] For the success in developing systemic gene carriers, it is essential to optimize the pharmacokinetics and intracellular trafficking to deliver the pDNA to the nucleus. To achieve this purpose, a Multifunctional Envelope-type Nano Device (MEND) was recently developed, in which the core of plasmid DNA, condensed by a polycation, was encapsulated by a lipid envelope. PEGylation and controlling the size of MEND are useful for stability of systemic circulation and tumor targeting by EPR effect. However, PEGylation results in a significant loss in transfection activity. In order to resolve this dilemma, a cleavable PEG-lipid composed of PEG/Matrix Metalloproteinase (MMP)-substrate peptide/DOPE (PPD) was synthesized, which is specifically cleaved by MMP in the extracellular space in tumor tissues. The function of PPD-modified MEND (PPD-MEND) as non-viral gene vector for cancer was evaluated in in vitro and in vivo. [Methods] N-terminal region of the peptide was reacted with MeO-PEG- CONHS. The C-terminal of the PEG-Peptide was conjugated with DOPE. The synthesis was confirmed by TOF-MS and 1H-NMR. MEND composed of DOTAP, DOPE, Cholesterol including a certain amount of PPD or PEG-DSPE were transfected in HT1080 and HEK293 cells, in which MMP is highly and poorly expressed, respectively. At 48 h after transfection, the transfection activity was assayed. The ability of PPD to improve the stability of the MEND in the systemic circulation was confirmed after i.v. administration. For measurement of blood concentrations, the lipid bilayers of MEND, PEG-MEND and PPD-MEND were labeled with 3H-Cholesteryl hexadecyl ether (CHE), and administered to mice via the tail vein. At 6 h post-injection, blood was collected and the radioactivity measured by liquid scintillation counting. [Results] TOF-MS and 1H-NMR analysis showed correct synthesis of PPD. The non-PEG-modified MEND (MEND) exhibited a high transfection activity in both cell lines. The transfection activity of PEG-MEND drastically decreased in both cell lines to less than 1% compared to MEND. The transfection activity of the PPD-MEND was enhanced by 35-fold compared to that of the PEG-MEND at 5% of PEG density. The blood concentration of PPD-MEND with 5% and 15% density of PEG was 10-fold and 35-fold higher than that of MEND, respectively, whereas it was slightly lower than that of PEG-MEND at the same PEG density. These results show that the PPD on MEND potently prolongs its systemic circulation. [Conclusion] The use of PPD provides a valuable function for in vitro transfection activity by virtue of its cleavable nature in response to a MMP-rich environment and for the stability of the MEND in the systemic circulation.

Determinación de anticuerpos frente al antígeno A-60 para el diagnóstico de la infección por M. tuberculosis: Una herramienta útil para la racionalización de la quimioprofilaxis en pacientes VIH

To identify M. tuberculosis infection in HIV patients by use of PPD and an ELISA test detecting the presence of antibodies against antigen A-60 of M. bovis. 116 incoming HIV patients were classified according to the CDC. The status of M. tuberculosis infection was probed with PPD (RT-23) and the state of anergy was estimated by a Multitest CM1 (Multitext). The presence of circulating antibodies of the IgG class against antigen A-60 was analysed by an ELISA. The clinical course of the patients was followed for 24 month. A positive serology (A-60) was found in 52.58% of the patients, coinciding with 70.45% of the positive PPD (p < 0.003). This statical observation was found when we studied all of the individuals, and those with more than 500 CD4 lymphocytes. The Multitext was positive in 11.11% of the patients with PPD (-), all of them without antibodies against A-60. However, 42.2% of the patients who were PPD and Multitext (-), had circulating antibodies against A-60. The following up of the patients during 24 months allowed the detection of 7 news cases of pulmonary tuberculosis, 4 of them had a positive A-60 serology, and 4 were anergy. HIV patients with M. tuberculosis infection have circulating antibodies against A-60 antigen of M. bovis with independence of their immunity status. In anergic patients the presence of this antibodies can be an useful tool for rationalizing the prophylaxis against M. tuberculosis. A seropositivity (A-60) indicates as well as does PPD a previous contact with M. tuberculosis.

Postpartum depression syndrome as a defense to criminal behavior

Though history records that women have suffered from PPD for centuries, little attention is directed to this serious malady in today's medical and legal communities. Medical research indicates that PPD is the result of the physical stress of pregnancy and childbirth, the social stress of the mothering role, or a combination of both. There are four phases of PPD: maternity blues, postnatal exhaustion, postnatal depression and puerperal psychosis. Victims of puerperal psychosis manifest bizarre behaviors — including the murder of their own children. Approximately 18 cases in the United States have involved the use of PPD as a defense to murder. British medical and legal authorities recognize PPD as a serious women's health issue, and as a viable insanity defense. Legal experts in the United States believe that the PPD defense will be used more frequently in this country. A review of the basic principles of the insanity defense supports the admission of this defense in legal proceedings.

Use of ppd and phosphatide antigens in an elisa to detect the serological response in experimental bovine tuberculosis

Five calves from tuberculosis free herds were each inoculated intranasally with 10(6) viable organisms of a field isolate of Mycobacterium bovis. Four of the calves developed acute tuberculosis. ELISAs employing protein and phosphatide extracts of M bovis as antigens were used to monitor the humoral response of the infected calves. Fourteen days after infection there was a dramatic increase in the level of antibodies demonstrated by the phosphatide antigen. This increase coincided with the first appearance of signs of the disease. The results suggest that the phosphatide antigen may be of potential value in detecting a humoral response, if present, in cattle infected with M bovis. The tests employing the protein antigen demonstrated a humoral response in only one of the infected calves and emphasises the importance of antigen selection to detect antibodies in tuberculous animals.

Improved Service Life of Automotive Suspension Bushings through the Use of Semi-Efficient Vulcanization Systems

Abstract The relative merits of antiozonants, efficient vulcanization systems, and semi-efficient vulcanization systems for natural rubber in dynamic applications have been previously evaluated in a number of laboratory studies. This report covers an evaluation of the effects of these three factors on the laboratory fatigue testing of automotive suspension bushings. The use of semi-efficient vulcanization systems along with a good soluble antioxidant will provide the optimum resistance to the combined effects of oxidation and mechanical fatigue experienced in this application. Efficient vulcanization systems produce products with very poor service life. The use of substituted p-phenylenediamine (ppd) antiozonants can be an advantage or disadvantage in compression fit bushings, depending upon the type of service. Excessive amounts of ppd at the rubber-to-metal interface can cause slippage and early failure; therefore, the use of ppd's must be approached with caution in this application.