Permeability and mechanical properties of gradient porous PDMS scaffolds fabricated by 3D-printed sacrificial templates designed with minimal surfaces.

In the present study, polydimethylsiloxane (PDMS) porous scaffolds are designed based on minimal surface architectures and fabricated through a low-cost and accessible sacrificial mold printing approach using a fused deposition modeling (FDM) 3D printer. The effects of pore characteristics on compressive properties and fluid permeability are studied. The results suggest that radially gradient pore distribution (as a potential way to enhance mechanically-efficient scaffolds with enhanced cell/scaffold integration) has higher elastic modulus and fluid permeability compared to their uniform porosity counterparts. Also, the scaffolds are fairly strain-reversible under repeated loading of up to 40% strain. Among different triply periodic minimal surface pore architectures, P-surface was observed to be stiffer, less permeable and have lower densification strain compared to the D-surface and G-surface-based pore shapes. The biocompatibility of the created scaffolds is assessed by filling the PDMS scaffolds using mouse embryonic fibroblasts with cell-laden gelatin methacryloyl which was cross-linked in situ by UV light. Cell viability is found to be over 90% after 4 days in 3D culture. This method allows for effectively fabricating biocompatible porous organ-shaped scaffolds with detailed pore features which can potentially tailor tissue regenerative applications. STATEMENT OF SIGNIFICANCE: Printing polymers with chemical curing mechanism required for materials such as PDMS is challenging and impossible to create high-resolution uniformly cured structures due to hard control on the base polymer and curing process. An interconnected porous mold with ordered internal architecture with complex geometries were 3D printed using low-cost and accessible FDM technology. The mold acted as a 3D sacrificial material to form internally architected flexible PDMS scaffolds for tissue engineering applications. The scaffolds are mechanically stable under high strain cyclic loads and provide enough pore and space for viably integrating cells within the gradient architecture in a controllable manner.

Comparison of vaginal ointment of honey and clotrimazole for treatment of vulvovaginal candidiasis: A random clinical trial.

BACKGROUND AND OBJECTIVE: Vulvovaginal candidiasis (VVC) is the most prevalent vaginitis in women, accounting for 10 million medical referrals a year. Vaginal clotrimazole is a drug of choice for VVC treatment. However, increased drug resistance to this microorganism has led to an interest in naturally derived antifungal drugs. This study was conducted to compare honey vaginal ointment and clotrimazole vaginal ointment for VVC treatment. METHODS: Eighty women diagnosed with VVC were assigned to two groups for honey ointment and clotrimazole ointment treatment using a simple randomization rule. The ointments were applied at night for seven days. The disease symptoms including inflammation, vaginal discharge, and irritation at baseline in the fourth and eighth days of treatment were examined and compared between the two groups. The data was analyzed by SPSS version 20 with the Friedman test, Chi-square test, and independent t-test. P<0.05 was considered as the significance. RESULTS: The two groups were similar for inflammation severity, irritation, and discharge at baseline. In both the groups, the symptoms disappeared after treatment. On the eighth day of treatment, there was a significant difference in inflammation and vaginal discharge between the two groups. Inflammation (P=0.002) and vaginal discharge (P=0.003) recovered better in the clotrimazole group. But there was no significant difference in irritation severity and satisfaction with treatment between the two groups. In the two groups, no side effects were reported. CONCLUSION: Honey contributes to treating VVC. Thanks to the popular positive attitudes of honey, its availability, no need for sterility, and its cost-effectiveness, it is a choice of treatment for VVC.

Susceptibility status of field populations of Rhipicephalus bursa (Acari: Ixodidae) to pyrethroid insecticides.

Rhipicephalus bursa is a two-host ixodid tick with wide distribution in north of Iran especially in Mazandaran province. Acaricide treatment is the main tick control measure; however, acaricide resistance occurs in hard ticks in many areas of the world including Iran. Comprehensive information on susceptibility status of Rhipicephalus bursa is lacking, therefore, this study is undertaken to determine the susceptibility status of the species to pyrethroid acaricides and probable biochemical underlying mechanisms of resistance. From May 2013 to March 2014, engorged females Rhipicephalus bursa were collected using standard entomological procedures from body surface of sheep, goat and cattle in different areas of Mazandaran province, northern Iran. Eleven and ten pooled tick populations were tested against cypermethrin and lambda-cyhalothrin, respectively using larval packet test. Population SC-16 showed a maximum resistance ratio of 5.79 against cypermethrin in Sari County when compared to the most susceptible population NH-16 and 63.64% of tick populations were resistant at LC99 level. With lambda-cyhalothrin, 30% of the tick populations were resistant with low level and NK-2 was the most resistant population with resistance ratio of 4.32 in Nowshahr County. The results of biochemical assays demonstrated elevated levels of monooxygenases, glutathione S-transferases and esterases in pyrethroid resistant populations tested.

An analysis of first-time blood donors return behaviour using regression models.

BACKGROUND AND OBJECTIVES: Blood products have a vital role in saving many patients' lives. The aim of this study was to analyse blood donor return behaviour. MATERIALS AND METHODS: Using a cross-sectional follow-up design of 5-year duration, 864 first-time donors who had donated blood were selected using a systematic sampling. The behaviours of donors via three response variables, return to donation, frequency of return to donation and the time interval between donations, were analysed based on logistic regression, negative binomial regression and Cox's shared frailty model for recurrent events respectively. RESULTS: Successful return to donation rated at 49·1% and the deferral rate was 13·3%. There was a significant reverse relationship between the frequency of return to donation and the time interval between donations. Sex, body weight and job had an effect on return to donation; weight and frequency of donation during the first year had a direct effect on the total frequency of donations. Age, weight and job had a significant effect on the time intervals between donations. CONCLUSION: Aging decreases the chances of return to donation and increases the time interval between donations. Body weight affects the three response variables, i.e. the higher the weight, the more the chances of return to donation and the shorter the time interval between donations. There is a positive correlation between the frequency of donations in the first year and the total number of return to donations. Also, the shorter the time interval between donations is, the higher the frequency of donations.

The effect of Ramadan fasting on LH, FSH, oestrogen, progesterone and leptin in pregnant women.

Many pregnant Muslim women fast during Ramadan. Leptin has an important role in the reproductive system and hormones. In this study, FSH, LH, oestrogen, progesterone and leptin were measured in the first, second and fourth week of Ramadan and the second week post-Ramadan, in 30 fasting pregnant women. Data were analysed using repeated measures ANOVA by SPSS. The weight and BMI did not change during the study. A significant change in FSH, oestrogen, progesterone and leptin was observed (p < 0.05). The lowest value of FSH was in the second week of Ramadan. Progesterone increased at the end of Ramadan and the second week after. Oestrogen increased significantly during Ramadan and decreased after Ramadan. A decreasing trend was seen in LH during the Ramadan and 2 weeks after (p < 0.1). Leptin decreased significantly 2 weeks after Ramadan. We found poor weight gain and hypoleptinaemia in pregnant fasted women during the study. Food restriction in pregnant fasted women during Ramadan may induce poor weight gain during pregnancy. These data confirm that Ramadan fasting by pregnant women may have potential risks during pregnancy. We recommend further study to evaluate long-term effects of Ramadan fasting during pregnancy in different countries with different food habits and traditions, to obtain reliable and documented data.

Immunogenicity and efficacy of Hoshino strain of mumps vaccine in Iran; two years study.

This report describes the immunogenicity and efficacy and long term immunity of Hoshino strain of Mumps (included in MMR Vaccine) in shahr-e-kord, Islamic Republic of Iran (I.R.Iran). A total of 338 Children aged 3-18 years were tested for Mumps IgG using enzyme-linked immunosorbent assay (ELISA). The proportion of susceptible, mumps IgG negative, children was 19.8% (67 subjects). Of the 67 susceptible children, 36 received the MMR vaccination and successfully completed the study. Blood was collected by venipuncture 3, 12, and 24 months after vaccination and serum samples were tested by ELISA for detection of Mumps IgM and IgG. The overall seroconversion rate was 86.1%, 77.7% and 75% at 3, 12, and 24 months after vaccination respectively.

Seroprevalence of mumps before inclusion of mumps vaccination in the Iranian expanded programme on immunization.

The current target groups for measles, mumps and rubella vaccination in the Islamic Republic of Iran are children at 12 months and 4-6 years. A study of the age-specific seroprevalenceRepublic of Iran are children at 12 months and 4-6 years. A study of the age-specific seroprevalence of antibodies against mumps in children aged 3-18 years in Shahrekord aimed to establish the needof antibodies against mumps in children aged 3-18 years in Shahrekord aimed to establish the need for booster vaccinations to cover non-immune children. Of 338 children, 19.8% were seronegative. Age-specific seronegativity was 33.3%, 20.5% and 4.6% in age groups 7-11, 12-14 and 15-18 years respectively. To obtain herd immunity, we suggest that for the next 5 years children aged 7-11 years entering guidance school are selected as the main group for vaccination.

Seroprevalence of mumps before inclusion of mumps vaccination in the Iranian Expanded Programme on Immunization

The current target groups for measles, mumps and rubella vaccination in the Islamic Republic of Iran are children at 12 months and 4-6 years. A study of the age-specific seroprevalence of antibodies against mumps in children aged 3-18 years in Shahrekord aimed to establish the need for booster vaccinations to cover non-immune children. Of 338 children, 19.8% were seronegative. Age-specific seronegativity was 33.3%, 20.5% and 4.6% in age groups 7-11, 12-14 and 15-18 years respectively. To obtain herd immunity, we suggest that for the next 5 years children aged 7-11 years entering guidance school are selected as the main group for vaccination

Study on the prevalence of dairy cattle lameness and its effects of production indices in Iran. A locomotion scoring base study.

In this current study, prevalence of lameness was detected and its changes during different parities, Days in Milk (DIM) and milk production were studies. In addition, effects of lameness on Open Days (OD) and Service per Conception (S/C) were studied. Three dairy farms on three scales (1: Large, approximately 900 milking cows, 2: Medium, approximately 100 milking cows and 3: Small, approximately 20 milking cows) were watched for lameness in 2005-2006. Locomotion Scoring (LS) by Sprecher method (1-5 point scale) has been done by videoing of the animals at the exit of the milking parlor. Videos were reviewed by two expert and mean of the each score used as score of the animal, cows with scores 1 and 2 recorded as non-lame and 3, 4 and 5 as lame cows. The average score of the lameness in autumn and spring recorded as 2.47 and 2.73, respectively that was higher significantly in spring. LS has been increased significantly by increasing parity and DIM, as highest scores were recorded in parity 4 and DIM 240-300. No significant differences between lame and non-lame cows were recorded in according to their milk production. The highest (percent in lame cows) scores were recorded in high producing cows. No significant difference in milk production has been recorded in different LS. However the average production of milk in lame cows were 1.08 L day(-1) less that non-lame cows. The average OD of the lame cows was significantly longer (52 days) than non-lame cows. Lame cows needed significantly higher service/conception (one) than non-lame cows. Median of OD and S/C has been increased by LS.

Flow cytometry with or without cytochemistry for the diagnosis of acute leukemias?

Ninety-three (93) cases of acute leukemia were assessed using flow cytometry and cytochemistry and assigned to one of four categories: myeloid, lymphoid, biphenotypic, and non-diagnostic. In leukemias designated as ALL or AML by both methodologies, there was lineage agreement in all but 3 of 71 cases (95.8%). However, when nondiagnostic or biphenotypic diagnoses made by either methodology were included, complete agreement occurred in only 77.4% of cases. Of 37 cases designated myeloid origin by flow cytometry, 33 (89.2%) were read as myeloid by cytochemistry. The four discordant diagnosis were read as lymphoid (2) or as non-diagnostic (2). Eighty percent of lymphoid leukemias were diagnosed as such by both flow cytometry and cytochemistry; one early B cell ALL was diagnosed as myeloid and 8 as non-diagnostic. Fifty percent (50%) of flow cytometry defined T-cell ALL were considered non-diagnostic by cytochemistry as compared to 17% of the total ALL group. Of the remaining four designated non-T cell ALL by flow cytometry and non-diagnostic by cytochemistry, three were read by flow cytometry to be standard pre-B ALL and one an early B-cell ALL. Only 2/9 leukemias considered biphenotypic by flow were identified as such by cytochemistry. Given (1) the potential importance of non-lineage expression in the prognosis of myeloid and lymphoid leukemias, (2) cytochemistry's impaired ability to diagnose biphenotypic, T-cell, and promyelocytic leukemias, and (3) the increased costs incurred in diagnosis when both modalities are used, perhaps it is time to re-examine the utility of performing both flow cytometry and cytochemistry as initial testing for leukemia categorization.

Chrysotile asbestos fibers mediate homologous recombination in Rat2 lambda fibroblasts: implications for carcinogenesis.

Asbestos fibers are widespread environmental carcinogens whose mutagenicity is now established. Nonetheless, the molecular nature of these mutations and the mechanisms by which they accelerate carcinogenesis remain poorly understood. We have assessed the ability of asbestos fibers to promote homologous recombination, a potent mechanism for generating intrachromosomal rearrangements, such as deletions, and mitotic recombination. For this, we have developed a new assay which determines the extent to which a marker gene present in DNA introduced by asbestos can recombine with homologous genes residing in a transfected cell. We have demonstrated that Calidria chrysotile fibers are mutagenic and are able to mediate transfection of molecularly marked mutant lacI genes in a manner that results in their preferential recombination with homologous wild-type genes in the transfected cell. Asbestos induced recombination events may play a significant role in asbestos mutagenesis and carcinogenesis, and promotion of recombination may underlie the well-recognized synergy of asbestos with other carcinogens.

Effects of H1 histones and a monoclonal autoantibody to H1 histones on clot formation in vitro: possible implications in the antiphospholipid syndrome.

Histones are known to bind anionic phospholipids (PLs). Binding of procoagulant PLs by histones released during cell injury/death may interfere with coagulation and may serve a local regulatory anticoagulant function. Histone H1 prolonged the PT and APTT of normal pooled plasma (NPP). These increased clotting times disappeared when anti-H1 monoclonal antibody (mAb) was added to the incubation. Dilute Russell Viper Venom Time was also prolonged with the addition of histone H1. When H1 was added to plasma from a patient with the antiphospholipid syndrome (APL plasma), there was a further prolongation of the abnormal APL clotting time which was partially corrected by anti-H1 mAb. Platelet neutralization times were increased with added H1 and were further increased using APL plasma. when disrupted endothelial cells were incubated with plasma with and without anti-H1 antibodies, the addition of anti-H1 antibodies decreased clotting times. These data support the theory that histones released during cell injury may have a regulatory anticoagulant role in clot formation and the anti-H1 effect of some APL plasmas may inhibit this, thereby contributing to thrombosis seen in APL patients.

Case report: fatal lymphoproliferative disease seven weeks after liver transplantation.

A 42-year-old man developed a lymphoproliferative disorder and died seven weeks after undergoing liver transplantation for primary biliary cirrhosis. At autopsy, diffuse large cell lymphoma was noted to involve almost every organ. Molecular analyses of DNA isolated from an enlarged periportal lymph node indicated the presence of Epstein-Barr virus sequences and several JH immunoglobulin gene rearrangements (consistent with the presence of more than one greatly expanded clone of lymphoid cells of B-cell lineage). This case underscores the possibility of the rapid emergence of lymphoproliferative disorder related to Epstein-Barr virus early after liver transplantation, masked by a concurrent episode of acute rejection.