Risk analysis of herbicide quinclorac residues in irrigated rice areas, Santa Catarina, Brazil.

Deterministic and probabilistic risk analyses were carried out for seven hydrographic basins in the State of Santa Catarina (Brazil), where irrigated rice is cultivated. Monitoring studies conducted in 1998/1999 and 1999/2000 had found that the herbicide quinclorac was the most frequently detected agrochemical residue, occurring in five of the seven hydrographic basins. In order to assess the ecological risk posed by quinclorac, median lethal concentration (LC(50)) and median effective concentration (EC(50)) data were obtained for quinclorac in toxicity tests with organisms routinely used in Brazil for this purpose. Experiments were carried out on microcosms associated with the irrigated rice crop to evaluate the effects of the herbicide on the natural plankton community. The deterministic analyses showed that the risk presented by the herbicide residues to the phytoplankton require mitigating action, while the probabilistic analysis revealed that the levels of risk for the aquatic community were acceptable. Field experiments showed that the recommended application concentration of the product directly affects phytoplankton and has an indirect, short-term effect on the zooplankton community.

A randomized trial of the efficacy of a new micronized formulation versus a standard formulation of isotretinoin in patients with severe recalcitrant nodular acne.

BACKGROUND: Isotretinoin is very frequently the drug of choice for the management of severe recalcitrant nodular acne. Recently, a new micronized and more bioavailable formulation of isotretinoin has been developed that permits once-daily administration in lower doses than usually used with standard isotretinoin (Accutane), regardless of whether it is taken with or without food. OBJECTIVE: Our purpose was to determine whether micronized isotretinoin and standard isotretinoin are clinically equivalent. METHODS: In this multicenter, double-blind, double-dummy study, 600 patients with severe recalcitrant nodular acne were treated with either 0.4 mg/kg of micronized isotretinoin once daily without food (n = 300) or 1.0 mg/kg per day of standard isotretinoin in two divided doses with food (n = 300). Lesion counts were monitored over 20 weeks. RESULTS: Both treatment groups in this well-controlled clinical trial experienced an equivalent reduction in the number of total nodules (facial plus truncal). In addition, an equivalent proportion of patients achieved 90% clearance of the total number of nodules. Both formulations had similar results for other efficacy variables. CONCLUSION: Once-daily use of the micronized and more bioavailable formulation of isotretinoin under fasted conditions is clinically equivalent to the standard twice-daily formulation under fed conditions in the treatment of severe recalcitrant nodular acne.

Safety of a new micronized formulation of isotretinoin in patients with severe recalcitrant nodular acne: A randomized trial comparing micronized isotretinoin with standard isotretinoin.

BACKGROUND: Isotretinoin is a very effective drug for treating severe recalcitrant nodular acne. A new micronized formulation of isotretinoin has been shown to be clinically equivalent to standard isotretinoin with improved bioavailability and minimal food effect. The safety profile of the micronized formulation has not been described previously. OBJECTIVE: The objective of this article is to report the incidence and intensity of adverse events found in a comparative, double-blind efficacy study that showed clinical equivalence of the new micronized formulation of isotretinoin and the standard isotretinoin formulation (Accutane). METHODS: Six hundred patients with severe recalcitrant nodular acne were treated with micronized isotretinoin (n = 300) under fasted conditions or standard isotretinoin (n = 300) under fed conditions. One cohort received single daily doses of 0.4 mg/kg of micronized isotretinoin without food and the other cohort received 1.0 mg/kg per day of standard isotretinoin in two divided doses with food. Adverse events were monitored during 20 weeks of drug therapy. RESULTS: The proportion of adverse events in most body systems was generally lower in patients receiving micronized isotretinoin than in those receiving standard isotretinoin. CONCLUSION: Micronized isotretinoin appears to have a safety profile similar to that of standard isotretinoin and to carry a lower risk of mucocutaneous events and hypertriglyceridemia.

Retinol administration to superovulated ewes improves in vitro embryonic viability.

Retinol and its metabolites, all-trans retinoic acid and 9-cis retinoid acid, are regulators of cellular growth, differentiation, and development and have been implicated in reproductive processes including folliculogenesis and embryonic survival. Three experiments were conducted to identify effects of retinoid treatment of superovulated ewes upon subsequent in vitro embryonic development. Ewes were treated with all-trans retinol (ROH), all-trans retinoic acid (RA), 9-cis retinoic acid (CIS), or vehicle (Control) on the first and last day of FSH treatment. Embryos were recovered at the morula stage, cultured in vitro for 96 h, and observed for blastocyst formation. Embryos from ROH-treated animals had a higher (p < 0.01) incidence of blastocyst formation than RA-, CIS-, or vehicle-treated animals (72% vs. 27%, 33% and 32%, respectively). In experiment 2, ewes were given ROH or vehicle and treated as above. ROH treatment resulted in an increased percentage of embryos forming blastocysts (70% vs. 22%, p < 0.05). In experiment 3, ewes were treated with ROH or vehicle, and embryos were collected at the 1- to 4-cell stage and cultured for 7 days. ROH treatment resulted in increased blastocyst formation (79% vs. 5%, p < 0.05). The majority of embryos (60% vs. 6%; p < 0.01)) from vehicle-treated animals failed to develop beyond the 8-cell stage in comparison with those from ROH animals. ROH treatment of superovulated ewes increased embryonic viability and positively impacted embryonic development.

Steroid regulation of retinol-binding protein in the ovine oviduct.

Two studies were conducted to identify retinol-binding protein (RBP) expression in the ovine oviduct and to determine the role of ovarian steroids in its regulation. Ewes were salpingectomized on Days 1, 5, or 10 of their respective estrous cycles, and oviducts were homogenized for RNA analysis, fixed for immunocytochemistry (ICC), or cultured for 24 h for protein analysis. ICC localized RBP to the epithelium of all oviducts. RBP synthesis was demonstrated by immunoprecipitation of radiolabeled RBP from the medium of oviductal explant cultures. Explant culture medium from oviducts harvested on Day 1 contained significantly more RBP than medium from oviducts collected on Days 5 or 10. Slot-blot analysis demonstrated that steady-state RBP mRNA levels were significantly higher on Day 1 than Day 5 or 10. In the second experiment, ovariectomized ewes were treated with estradiol-17beta (E2), progesterone (P4), E2+P4 (E2+P4), or vehicle control, and oviducts were analyzed as above. P4 alone or in combination with E2 significantly reduced steady-state RBP mRNA levels compared to those in E2-treated animals. Oviductal explants from E2- and E2+P4-treated animals released 3- to 5-fold more RBP into the medium than control and P4 treatments as determined by ELISA. RBP synthesis of metabolically labeled RBP was increased by E2 and E2+P4 treatments. This study demonstrates that P4 applied on an estradiol background negatively regulates RBP gene expression in the oviduct whereas estradiol appears to stimulate RBP synthesis and secretion.

Immunolocalization of retinol-binding protein and profiles of its mRNA as related to testicular development in the beef bull.

A study was conducted to identify the cell types that express retinol-binding protein (RBP) in the bovine testis and to compare relative steady-state levels of RBP mRNA expression at different times of testicular development. At the ages of 10 (n = 3), 20 (n = 8), and 34 (n = 7) wk, Angus bulls were bled three times at 1.5-hr intervals, then surgically castrated. Blood samples were analyzed for follicle-stimulating hormone (FSH), luteinizing hormone (LH), and testosterone (T), by radioimmunoassay and the degree of seminiferous tubule development was evaluated histologically in sections of fixed tissue samples stained with hematoxylin and eosin. Immunolocalization of RBP was based on the biotin-strepavidin-horseradish peroxidase method. Testis weight and concentrations of LH and T increased with age (P < 0.05), but those of FSH did not change (P > 0.05) between 10 and 34 wk. Seminiferous tubules at 10 wk contained immature Sertoli cells and gonocytes whereas, at 20 wk, spermatogonia and few spermatocytes were detected. At 34 wk, Sertoli cells appeared differentiated and spermatids were observed. RBP was immunolocalized in Sertoli, Leydig, and peritubular cells at the ages of 10, 20, and 34 wk. Furthermore, no differences in staining between Sertoli cells from tubules with or without germ cells were detected. Northern hybridization of testicular RNA with an RBP cDNA probe revealed the presence of a 1.4-Kb mRNA, which was similar to previous RBP transcripts found in other bovine tissues. Quantitative slot blot analysis revealed that steady-state RBP mRNA levels were 50% higher at 10 wk (P < 0.05) than at 20 and 34 wk of age.

Clinical study: peristomal skin irritation in colostomy patients.

A prospective, controlled, clinical study was conducted to evaluate the effect of skin barriers and adhesives on the incidence of peristomal skin irritation. Colostomy patients eligible to participate were randomly assigned one of two sets of 10 one-piece pouching systems. At mid-study, after using the first 10 pouches, patients were allocated 10 pouches from the alternate pouching system. Each pouching system was worn for a maximum of 24 hours. One-hundred twelve patients were enrolled in the study. At baseline, 8 percent of patients had some erythema. At the end of the study period, 26 percent of patients exhibited signs of skin irritation. Patients were significantly more likely to develop skin irritation following use of the Karaya-based barrier than following use of the pectin-based barrier product (Wilcoxon Rank Sum Test, p < 0.01). Similarly, the type of tape used to secure the pouching system significantly influenced the incidence of skin irritation. Analysis of the change in skin condition as it relates to all evaluated variables; i.e. pouching system, stoma shape, stoma size, stoma length and irrigation, showed that only the type of product used was significantly associated with a change in skin condition. This is the first report of a controlled clinical study to evaluate the effect of pouching systems and patient/stoma variables on skin integrity in colostomy patients. These findings confirm that skin irritation can be a considerable problem, even in patients who use irrigation techniques.(ABSTRACT TRUNCATED AT 250 WORDS)

Oviductal fluid and growth factors failed to enhance development of porcine embryos.

Porcine embryos (1-, 2- and 4-cell) were cultured in a basal medium consisting of Krebs-Ringer bicarbonate buffer supplemented with oviductal fluid and several growth factors and observed for further development. Oviducts were flushed at either 48 h (Experiment 1) or 96 h (Experiment 2) after the onset of estrus. Observations were made every 48 h (Experiment 1) or 12 h (Experiment 2) until failure of the embryos to develop for 2 consecutive observations. Embryos were scored 0 = no development, 1 = cleavage, 2 = morula, 3 = blastocyst, or 4 = hatched blastocyst. In the first experiment, development of 1-, 2- and 4-cell embryos (n=282) in the basal medium supplemented with oviductal fluid (4:1) or 3 sets of growth factors, was less or equal to one cleavage stage. Those embryos cultured in the basal medium supplemented with bovine serum albumin (fatty acid free) (BSA) advanced to the blastocyst stage. In the second experiment, 96 h aged embryos (n=142) were cultured in the basal medium supplemented with IGF-1 and - 2 and EGF, or with BSA alone or with BSA and the three growth factors. In the treatments without BSA, the embryonic development was less than one cleavage, whereas in those treatments with BSA, embryos advanced beyond hatching and began to expand. We conclude that for culture of porcine embryos, supplementation with several growth factors or with oviductal fluid, in the concentration used in this study, was of little benefit at this stage of development. However, the type of BSA significantly affected development. More than 90% of the embryos reached the morula and blastocyst stages in medium than included BSA (fatty acid free).

HP, GC and PI polymorphisms in sixteen central Indian tribal populations.

HP, GC and PI polymorphisms have been typed on 16 Central Indian tribal populations with a total of 1658 individuals. The distribution of allele frequencies shows a statistically highly significant heterogeneity, which may be caused by several microevolutionary factors, such as genetic drift, social and geographic isolation. Some new variants were observed in both the GC system (GC 2Cmah) and in the PI system (PI Yori). The PI variants are more frequent and are found in most of the 16 populations under study whereas the GC variants are rather infrequent and restricted to only three populations.

Identification and content of insulin-like growth factors in porcine oviductal fluid.

Oviductal fluid (OvF) was collected from gilts by indwelling catheters during the estrous cycle and analyzed for content of insulin-like growth factors (IGF-I, IGF-II). Group 1, composed of 9 gilts in a summer environment near a boar, yielded mean daily fluid volumes of 1.18 +/- 0.16 ml during estrus and 0.69 +/- 0.03 ml post-estrus. Group 2, composed of 7 gilts in a moderate-temperature, light-regulated room, yielded 1.20 +/- 0.18 ml during estrus and then OvF flow essentially stopped. Serum samples were also collected 2 times daily during the cycle and analyzed along with the OvF for IGF-I and IGF-II. Serum was also analyzed for estradiol-17 beta (E2). For group 1, OvF content (concentration x fluid volume) of IGF-I and IGF-II was greater (p less than 0.05) at estrus than pre- and post-estrus. Daily mean content values (ng/day) for IGF-I and IGF-II during peri-estrus were 30.9 +/- 6.3 and 62.2 +/- 12.3, respectively. During nonestrus, values were 6.8 +/- 6.3 and 11.7 +/- 12.3, respectively. For group 2, OvF content of IGF-I and IGF-II during estrus was similar to that of group 1. Whereas IGF content differed between estrus and nonestrus periods, IGF concentrations were similar (p greater than 0.05), a finding that results from the difference in OvF produced. Compared with OvF concentrations of IGF for a given pig, blood plasma concentrations of IGF-I and IGF-II were 2- to 5-fold higher in the plasma sample collected the same day.(ABSTRACT TRUNCATED AT 250 WORDS)

Investigations on the variability of blood group polymorphisms among sixteen tribal populations from Orissa, Madhya Pradesh and Maharashtra, India.

Sixteen tribal populations from Orissa, Madhya Pradesh and Maharashtra have been typed for the polymorphic blood group systems A1A2B0, MNSs, Rhesus, Kell, Duffy and Diego. The heterogeneity in the distribution of haplotype and allele frequencies, respectively, is partly considerable. It is supposed that this is due to the operation of several microevolutionary factors, such as genetic drift, social and geographic isolation and gene flow. This is discussed in detail.

In situ nick translation of human chromosomes using Alu I: unmasking of recognition sites by proteinase K pretreatment.

Human chromosomes prepared according to routine methods were treated with the restriction endonuclease Alu I followed by staining with Giemsa solution or fluorescent dyes. This procedure results in a C-band-like appearance of the chromosomes due to removal of DNA from euchromatic chromosomal regions. The resistance of heterochromatic regions against cleavage by the enzyme has mainly been interpreted by the absence or rareness of recognition sites for this particular enzyme in these regions. Proteinase K pretreatment followed by a nick translation procedure with Alu I was combined to check this hypothesis. The results show that heterochromatic chromosomal regions can also be labelled. Thus, they are not characterized by a lack of recognition sites. Gradual deproteinisation of chromosomes changes the labelling pattern from a reverse C-banding pattern to a C-band-like appearance. The resistance of heterochromatic chromosomal parts revealed by the technique is mainly due to local chromatin configuration rather than to the underlying DNA sequence itself.

Serum protein polymorphisms (HP; TF-, GC- and PI-subtypes) in Sardinia.

Haptoglobin (HP), transferrin (TF), group-specific component (GC) and alpha-1-antitrypsin (PI) polymorphisms have been studied in Sardinia and the following gene frequencies have been found: HP*1 = 0.389, TF*C1 = 0.754, TF*C2 = 0.213, TF*C3 = 0.032, GC*1F = 0.193, GC*1S = 0.546, GC*2 = 0.260, PI*M1 = 0.607, PI*M2 = 0.221, PI*M3 = 0.126, PI*S = 0.040 and PI*Z = 0.006. These findings confirm the genetic uniqueness of Sardinians compared to the other Italian populations.

The use of single-channel compression for the improvement of speech intelligibility.

In this study, speech perception with commercially available linear and single-channel input- and output-dependent compression aids was investigated. Although compression has been introduced as a method of limiting the maximum output, theoretically expectations have been raised that a gain in speech intelligibility could also be obtained by a better use of the reduced dynamic range of the patient. It turned out that there was no significant difference in speech reception thresholds obtained both in quiet and in noise between the aids used for a group of 12 hearing-impaired hearing-aid users as a whole, or for different subgroups thereof.