An efficient protocol for the synthesis of new camphor pyrimidine and camphor thiazole derivatives using conventional and microwave irradiation techniques and in vitro evaluation as potential antimicrobial agents.

BACKGROUND: A series of new pyrimidines and thiazoles containing camphor moiety were synthesized under both conventional and microwave irradiation techniques. METHODS: The condensation of camphor either with aminoguanidine or thiosemicarbazide gives the camphor hydrazine carboximidiamide 2 and the camphor thiosemicarbazone 3, respectively. Refluxing of 3 with chloroacetonitrile afforded the camphor thiazol-4-imine 4. Compounds 2 and 4 were used as precursors for the synthesis of target products. RESULTS: The reaction of 2 with different species such as arylidene malononitrile, acetylacetone, and ethyl acetoacetate gave the corresponding camphor pyrimidine derivatives 5a,b-7 while refluxing of compound 4 with different reagents e.g. aldehydes, isatin, ninhydrin, acetic anhydride, benzene sulphonyl chloride, and p-nitro-benzoyl chloride afforded the camphor thiazole derivatives 8a-d-13, respectively. CONCLUSION: A comparison between the conventional way and the eco-friendly microwave irradiation method occurred in the synthesis of the same compounds, which the latter was more efficient. The elemental analysis, FT-IR, 1H NMR, 13C NMR, and Mass spectra confirm the structures of the obtained new compounds. The potential use of some selected derivatives as antimicrobial agents was investigated and gave promising results.

Effect of environmental iodine deficiency (EID) on foetal growth in Nigeria.

BACKGROUND & OBJECTIVES: There is scarcity of information on impact of iodine deficiency on growth and development of newborns, both pre-term and term babies. The present study was carried out to see the impact of iodine deficiency (ID) on the intrauterine foetal growth and development in terms of birth weight (BW) in an African population living in an iodine deficient zone. METHODS: The maternal and cord serum thyroid parameters at term delivery (38-40 wk of gestation) were measured and correlated with the birth weights of the corresponding newborns, and the results compared between those assessed in an ID zone (Jengere region of Bassa district, Plateau State, Nigeria) and with that of non ID (Control) zone, Jos, the State capital. RESULTS: The level of maternal and neonatal thyroid function were significantly reduced in the group with low birth weights (<2.5 kg) as compared to the level seen in normal birth weights category in both control (Jos) and ID (Jengere) regions. Both in non ID and ID regions the maternal serum thyroxine (T4), thyroxine binding globulin (TBG) and free thyroxine index (FT4I) were positively correlated (P<0.005) with BW of term babies while thyroid stimulating hormone (TSH) (P<0.005) and thyroxine binding capacity (TBK) (P<0.05) showed negative correlation. Maternal T3 and T3/T4 ratio did not show any correlation with BW in Jos, while in the ID region of Bassa the BW showed a positive correlation (P<0.005) with the maternal serum T3 and T3/T4 ratio. Cord serum analysis of the term babies revealed that the BW was positively correlated with its T4, triiodothyronine (T3), TBG, FT4I and T4/TBG ratio (Jos only) (P<0.005) in both ID region of Bassa and non ID control zone of Jos. Cord serum TSH and TBK showed negative correlation (P<0.005) with BW. Thyrotrophin releasing hormone (TRH) stimulation test revealed that mothers with small for date (SFD) babies at term were more hypothyroid compared to the level of thyroid function seen in the women delivering normal babies. INTERPRETATION & CONCLUSION: Maternal thyroid hormone plays a significant role in the intrauterine foetal growth and development, and the smaller babies and their corresponding mothers, in an ID affected area are functionally sub-thyroid in greater proportion due to prevailing long standing environmental iodine deficiency (EID). Maternal T3 is an important factor in the defence of foetus in ID regions.

Sperm chromosomal abnormalities in patients with unexplained recurrent abortions.

Cytogenetic studies showed that about half of concepti were chromosomally abnormal in first trimester abortions. Sperm chromosomal abnormalities in men with normal karyotype could occur during spermatogenesis. The objective of this study was to evaluate sperm chromosomal abnormalities in patients with unexplained recurrent abortions. A total of 14 couples with normal karyotype, and negative workup for endocrine, immune and anatomical causes of recurrent abortion was investigated. Semen analysis was performed and chromosomal abnormalities were assessed by fluorescent in situ hybridization for chromosomes 13, 18, 21, X and Y. The average number of abortions was 5.8. The incidence of chromosomal abnormalities was 16.5% that was higher when compared to baseline (4.6%). In conclusion, a high rate of sperm chromosomal abnormalities was observed in recurrent abortion patients. These abnormalities might form during spermatogenesis since all patients had normal karyotype. Sperm chromosomal abnormality analysis can be included into recurrent abortion workup when no other cause is detected.

Day 5 versus day 3 embryo transfer: a controlled randomized trial.

Blastocyst transfer has been suggested to improve implantation rate without affecting pregnancy rate. The aim of this study was to compare the pregnancy and implantation rates of day 3 and 5 transfers in a prospective randomized manner. Patients with four or more zygotes were randomly allocated on day 1 to either day 3 or 5 transfers. Fertilization was achieved through regular IVF or intracytoplasmic sperm injection. Zygotes were kept in Medicult IVF medium for day 3 transfers and transferred into G1.2 and G2.2 on day 1 and 3 respectively for day 5 transfers. The morphologically best two or three embryos or blastocysts were chosen for transfer in both groups. Overall pregnancy rates per embryo transfer were the same (39%) in day 3 and 5 transfers. Implantation rates were 21 and 24% for day 3 and 5 transfers respectively. The pregnancy and implantation rates for day 5 transfers were significantly affected by the availability of at least one blastocyst to transfer and the number of zygotes. The number of good quality embryos on day 3 also significantly affected pregnancy and implantation rates on day 5 transfers. Multiple gestation rate, number of abortions and ongoing pregnancies were similar in both groups. In conclusion, day 3 and 5 transfer had similar pregnancy, implantation and twinning rates. Currently, day 5 transfers have no advantages over day 3 transfers.

Advanced surgical sperm recovery is a viable option for intracytoplasmic sperm injection in patients with obstructive or nonobstructive azoospermia.

OBJECTIVE: To determine whether advanced sperm retrieval is appropriate in cases of obstructive and nonobstructive azoospermia. DESIGN: Prospective controlled study. SETTING: Tertiary care center. PATIENT(S): Men with obstructive and nonobstructive azoospermia, and their partners. INTERVENTION(S): Surgical sperm retrieval followed by intracytoplasmic sperm injection (ICSI) after 4 or 48 hours. MAIN OUTCOME MEASURE(S): Fertilization and pregnancy rates. RESULT(S): Advanced and fresh surgical sperm recoveries for ICSI were performed in 54 and 230 cycles, respectively. Patient demographics and cycle parameters were comparable. Two hundred forty-one (56.3%) of 428 injected eggs in the advanced retrieval group were fertilized, compared with 955 (56.6%) of 1,686 eggs in the fresh retrieved group (P=.94). There was no statistically significant difference in the pregnancy rates per ET between groups: 38.2% (18 of 47) in the advanced retrieval group and 39.9% (73 of 183) in the fresh sperm recovery group (P=.97). CONCLUSION(S): Testicular and epididymal sperm recovery can be safely performed 48 hours before ICSI. This facilitates planning, and, in cases of failure to retrieve sperm, hCG administration and ovum pick-up can be canceled, thereby reducing costs and eliminating the risk of ovarian hyperstimulation.

Low plasma levels of hCG after 10,000-IU hCG injection do not reduce the number or maturation of oocytes recovered in patients undergoing assisted reproduction.

PURPOSE: Our purpose was to determine whether there is a correlation between human chorionic gonadotropin (hCG) blood levels and oocyte maturation. METHODS: Three samples of blood were obtained at different times from hCG administration as follows: 12 hr, 36 hr, during oocyte recovery, and at 84 hr, when the patient comes for embryo transfer. RESULTS: A total of 5036 oocytes was retrieved from 404 patients prospectively recruited between April 1996 and March 1997. The percentage of metaphase-II oocytes at different blood levels ranged from 84 to 88%. The general trend does not show any significant increase in percentage of metaphase-II oocytes in association with an increasing serum hCG concentration. CONCLUSIONS: The results of this study suggest that at 12, 36, and 84 hr after hCG administration, levels as low as 50, 45, and 9 IU/L of hCG, respectively, are equally potent as higher levels at initiating maximal oocyte maturity.

Predicting empty follicle syndrome.

OBJECTIVE: To determine a simple predictive test for empty follicle syndrome before oocyte retrieval. DESIGN: Retrospective correlation analysis. SETTING: Patients attending Nottingham University Research and Treatment Unit, a tertiary, university-based assisted reproductive technologies (ART) program between April 1, 1994 and March 31, 1995. PATIENT(S): Six women in whom no oocytes were retrieved after superovulation for ART (empty follicle syndrome) were compared with 11 women with successful oocyte retrieval. INTERVENTION(S): Subcutaneous buserelin acetate plus IM hMG and hCG were used for superovulation. Oocyte retrieval was transvaginal and ultrasound guided. MAIN OUTCOME MEASURE(S): Ultrasound measurement of follicular growth and serum E2 levels during superovulation. Serum beta-hCG levels before and 36 hours after hCG administration IM. Number of oocytes retrieved. RESULT(S): Before hCG administration, beta-hCG was not detectable in the serum. The serum beta-hCG 36 hours after hCG was 209 +/- 16.7 mIU/mL (conversion factor to SI units, 1.0; mean +/- SEM, range 106 to 290 mIU/mL) in women with successful oocyte retrieval and 4 +/- 1.8 mIU/mL (range 0 to 9 mIU/mL) in empty follicle syndrome. This difference was significant. CONCLUSION(S): Empty follicle syndrome is associated with very low bioavailability of beta-hCG and can be predicted by measuring serum beta-hCG level 36 hours after IM hCG administration.

Model for simulating the effects of management practices on pesticide concentrations in groundwater.

This manuscript describes the RUSTIC model and presents the results of an example application. RUSTIC links three subordinate models in order to predict pesticide fate and transport through the crop root zone, unsaturated zone, and saturated zone to drinking water wells: PRZM, VADOFT, and SAFTMOD. PRZM is a one-dimensional finite-difference model which accounts for pesticide fate and transport in the crop root zone. This release of PRZM incorporates several features in addition to those simulated in the original PRZM code: specifically, soil temperature simulation, volatilization and vapor phase transport in soils, irrigation simulation and a method of characteristics (MOC) algorithm to eliminate numerical dispersion. PRZM is now capable of simulating fate and transport of the parent compound and up to two daughter species. VADOFT is a one-dimensional finite-element code which solves the Richard's equation for flows in the unsaturated zone. The user may make use of constitutive relationships between pressure, water content, and hydraulic conductivity to solve the flow equations. VADOFT may also simulate the fate and transport of two parent and two daughter products. SAFTMOD is a two-dimensional finite-element model which simulates saturated solute flow and transport in either an X-Y or X-Z configuration. The codes are linked together with the aid of a flexible execution supervisor which allows the user to build models which are tailored to site-specific situations. In order to perform exposure assessments, the code is equipped with a Monte Carlo pre- and post-processor. The application of the model is to a potato field on Long Island, New York. The results indicate that RUSTIC is capable of realistically matching data observed in downgradient monitoring wells following 3 years of aldicarb application.