Mahmoud Abd El Hafez M. Adam

A card agglutination test (CATT/T. evansi) was evaluated for detection of antibodies against Trypanosoma evansi (T. evansi) in experimentally and naturally infected buffaloes. Four calves were inoculated with a strain of T. evansi isolated from a dromedary camel. Parasitological examination of the calves revealed trypanosomes in the blood from days 4 to 9 post-inoculation (PI). General emaciation appeared from day 26 PI and aggravated until the end of the experiment (day 88 PI). Antibodies against T. evansi were detectable from day 8 PI till the end of the experiment. Parasitological examination of 200 water buffalo blood samples obtained from slaughterhouses revealed negative results. Serological examination of these animals showed that 48 (24%) water buffaloes had anti-T. evansi antibodies.

BACKGROUND: Angiogenesis is essential for solid tumor growth. It is induced by tumor cells through stimulatory angiogenic peptides, one such peptide is vascular endothelial growth factor (VEGF).

PURPOSE: The ultimate aim of the work is to investigate the possible role of VEGF as an early biomolecule involved in the progression of pediatric malignant tumors with high metastatic potential.

PATIENTS AND METHODS: Forty-five pediatric patients were studied. They included four groups with malignant solid tumors suffering from Ewing's sarcoma, osteosarcoma, neuroblastoma and rhabdomyosarcoma. In addition, a healthy control group including fifteen age and sex matched children was included in the study. Serum VEGF levels were determined by ELISA technique.

RESULTS: The level of VEGF was significantly higher in all types of solid tumors compared to normal healthy children. The mean values obtained for patients and controls were 429.44 +/- 258.55 pg/ml and 79.36 +/- 63.81 pg/ml, respectively. No significant difference was detected in the level of VEGF among males and females. Also, no statistically significant difference was detected among the different types of malignant tumors. However, a marked significant difference was elucidated between metastatic and non-metastatic cancer patients, the values recorded were 753.33 +/- 173.64 pg/ml and 267.5 +/- 75.54 pg/ml, respectively (p < 0.001). Furthermore the results showed that 207 pg/ml of serum level of VEGF is the optimal cut-off value (mean +/- 2 SD of control) with sensitivity of 87% and specificity of 100%. Using the receiver operating characteristic (ROC) curve analysis,the area under the curve (0.917) indicated the validity of using serum VEGF level in the diagnosis of all different types of pediatric malignant solid tumors with high potentiality to metastasis.

CONCLUSION: VEGF is an angiogenic stimulatory peptide. Its serum level could be a reliable marker in assessing pediatric malignancies with high metastatic potentials.

AIM OF THE WORK: The aim of the present study is to document the antitumor activity of the combination of gemcitabine and cisplatin for the treatment of advanced NSCLC, asses the nature and severity of the side effects and elicit the impact of the combination chemotherapy on progression free survival and overall survival.

PATIENTS AND METHODS: From August 1997 to August 2001, we conducted a phase II study of gemcitabine and cisplatin in 60 chemonaive patients (21 stage IIIB and 39 stage IV). For the first 34 cases, gemcitabine was given at a dose of 1,000 mg/m2 IV on days 1, 8 and 15 with cisplatin 100 mg/m2 on day 15, every 28 days. In the following 26 patients, the regimen was modified to gemcitabine 1,250 mg/m2 days 1 and 8 and cisplatin 80 mg/m2 day 1, every 21 days.

RESULTS: Patients included 53 males and 7 females [median age, 52 years (range, 28-69)]. Twenty-nine had adenocarcinoma, 18 large-cell carcinoma and 13 squamous-cell carcinoma. Thirty-one patients had a performance status (PS) of 2 and 22 presented with weight loss. All patients were evaluable for response. Three patients achieved a complete response (CR) and 22 had partial response (PR), giving an overall response of 41.7%, with a median duration of 10 months (range, 4-46 months). The time to progression (TTP) was 8 months (range, 2-46 months), with a median overall survival of 9 months (range, 2-46 months). The one-year survival rate was 30.3% for the entire study population, 44% for responders, and statistically improved in patients with a PS of I and those with no weight loss. A total of 255 cycles were administered (median, four cycles/patient). Myelosuppression was significant (but manageable) with grade 3/4 neutropenia in 32.6% of cases, anemia in 18.6% and thrombocytopenia in 20.4%. Nonhematologic toxicity was limited to grade 3/4 nausea and vomiting in 28.8% of cases and impaired liver enzymes in 13.6%.

CONCLUSION: Inspite of the relatively poor prognostic characteristics in the study population, gemcitabine and cisplatin, was an effective combination with tolerable, manageable toxicity in advanced NSCLC.

OBJECTIVE: The aim of this study was to clarify the effect of hypoxia on the physiologic inhibition system of coagulation including protein S, protein C, and antithrombin III and to study their effect on thromboembolic accidents of hypoxic newborns.

DESIGN: Clinical study including ten hypoxic-ischemic neonates and ten normal neonates as a control group.

DATA SOURCES: MEDLINE, pediatric textbooks, neonatal intensive care unit, Department of Paediatrics, Faculty of Medicine, Cairo University.

RESULTS: The results of this study revealed a marked decrease in the level of the physiologic inhibition system of coagulation including antithrombin III, protein C, and protein S in 100% of the hypoxic-ischemic neonates compared with the control group (p <.001) before the occurrence of thromboembolic complications. Fifty percent of the hypoxic-ischemic neonates developed disseminated intravascular coagulation and died, 40% developed necrotizing enterocolitis and rectal bleeding, 20% developed hematuria, 30% developed hematemesis, 20% developed intracranial hemorrhage, and 100% had convulsions.

CONCLUSIONS: In this study, we evaluated the effect of asphyxia on the physiologic inhibition system of coagulation in neonates. Care providers should suspect hypoxia resulting from any obstructed labor and perform the necessary laboratory investigations for coagulation, including antithrombin III, protein C, and protein S levels, to help prevent thromboembolic accidents in asphyxiated neonates, including disseminated intravascular coagulation, necrotizing enterocolitis, and intracranial hemorrhage. Based on the development of antithrombin III and protein C concentrates, which are commercially available, require minimal monitoring, and have very few side effects, the time is ripe for evaluation of optimal treatment for thromboembolic accidents after neonatal asphyxia. This could be even more important if successful neuroprotectant strategies are also developed.

We present the results of using a simple Ilizarov fixator frame in treatment of 66 feet in 52 patients (mean age 8.5 years) of 58 relapsed and eight neglected clubfeet with grade III or IV severity with a mean follow-up of 40 (26-58) months. Our frame, in spite of being simple and easy for surgeons and patients to handle, achieved satisfactory correction comparable to the literature.

PURPOSE: We previously found a statistically significant number of cytokeratin 19 (CK19)+ cells in peripheral blood (PB) of stage IV breast cancer (BC) patients compared with those of healthy volunteers, using a quantitative real-time reverse transcription-PCR. We aimed to apply the technique on bone marrow (BM) of primary operable BC patients. Pre- and postoperative PB samples of these patients were further analyzed to investigate possible shedding of CK19+ cells during the operation.

EXPERIMENTAL DESIGN: In 54 primary operable BC patients, we analyzed 50 BM samples taken preoperatively and 297 PB samples. PB samples were collected before surgery; immediately after surgery; on the first, second, and fifth day postoperatively; and one month postoperatively.

RESULTS: In BM of controls and BC patients, we detected a median of 28 and 568 CK19+ cells/5 x 10(6) leukocytes, respectively (P < 0.001). In preoperative blood (B-1) samples, we measured a median of 109 CK19+ cells. Using the upper limit of 95% confidence interval of controls as cutoff, 74% and 52% of BM and (B-1), respectively were considered CK19+. There was no significant correlation between CK19+ cells in BM and (B-1) and classical prognostic factors. We found no significant difference between blood samples at different time points with respect to the average CK19+ cells.

CONCLUSIONS: In primary BC patients, we detected high numbers of CK19+ cells in BM and PB (B-1) samples compared with controls. However, no significant correlation between the presence of CK19+ cells in BM and PB and classical prognostic factors was found. We detected no statistically significant influence of surgical manipulation on CK19+ cells.

The X-linked androgen insensitivity syndrome (AIS) encompasses a heterogeneous group of defects in the androgen receptor (AR) that result in varying degrees of undermasculinization. In the current study, we characterize the R840S mutation on exon 7 of the AR ligand-binding domain. The Egyptian patient, who had been reared as female, presented ambiguous genitalia at 6.5 yr. Diagnosis of partial AIS (PAIS) was based on clinical phenotype and laboratory evidence of good testosterone response and normal testosterone/dihydrotestosterone (T/DHT) ratio. The therapeutic response to testosterone depot injections justified reassignment to male sex. To our knowledge, this mutation has been reported only once in two Brazilian brothers with PAIS. Three other mutations of this residue (R840C; R840G, nonconservative; and R840H, conservative) have been reported in patients with PAIS and, when expressed in vitro, they led to subnormal transactivation of a reporter gene. Each of these mutations was associated with a very diverse spectrum of phenotypes. These data highlight the role of the AR ligand-binding pocket (LBP) in the expression of transcriptional activity during prenatal sex differentiation.

Capillaria philippinensis is an emerging infection in Egypt. Reports in children are scarce. We report here two sisters with C. philippinensis infection, aged 8 and 12 years. Their father was a fisherman and they had a habit of picking small pieces of uncooked fish to eat while their mother prepared their meals. They came from El-Menia governorate, which lies in the northern part of Upper Egypt. Most reported cases from Egypt come from this governorate and nearby areas. Both sisters had persistent profuse watery diarrhea of 12 months' duration. Their weights were below the 5th percentile for age. Both were hypoalbuminemic, but only the younger had pedal edema. Both had hypokalemia and hyponatremia. During the course of their illness they were repeatedly admitted to different hospitals and received intravenous fluids, but the correct diagnosis was not reached. Diagnosis was made by stool examination at our hospital when eggs and larvae were detected in stool samples. Although a diagnosis was promptly made, the older sister who suffered from pneumonia and septic shock unfortunately died a few days after admission. The younger sister was treated successfully with albendazole 200 mg twice daily. Diarrhea abated, pedal edema disappeared, and she started to gain weight.

Capillaria philippinensis is an emerging infection in Egypt. Reports in children are scarce. We report here two sisters with C. philippinensis infection, aged 8 and 12 years. Their father was a fisherman and they had a habit of picking small pieces of uncooked fish to eat while their mother prepared their meals. They came from El-Menia governorate, which lies in the northern part of Upper Egypt. Most reported cases from Egypt come from this governorate and nearby areas. Both sisters had persistent profuse watery diarrhea of 12 months' duration. Their weights were below the 5th percentile for age. Both were hypoalbuminemic, but only the younger had pedal edema. Both had hypokalemia and hyponatremia. During the course of their illness they were repeatedly admitted to different hospitals and received intravenous fluids, but the correct diagnosis was not reached. Diagnosis was made by stool examination at our hospital when eggs and larvae were detected in stool samples. Although a diagnosis was promptly made, the older sister who suffered from pneumonia and septic shock unfortunately died a few days after admission. The younger sister was treated successfully with albendazole 200 mg twice daily. Diarrhea abated, pedal edema disappeared, and she started to gain weight.

Capillaria philippinensis is an emerging infection in Egypt. Reports in children are scarce. We report here two sisters with C. philippinensis infection, aged 8 and 12 years. Their father was a fisherman and they had a habit of picking small pieces of uncooked fish to eat while their mother prepared their meals. They came from El-Menia governorate, which lies in the northern part of Upper Egypt. Most reported cases from Egypt come from this governorate and nearby areas. Both sisters had persistent profuse watery diarrhea of 12 months' duration. Their weights were below the 5th percentile for age. Both were hypoalbuminemic, but only the younger had pedal edema. Both had hypokalemia and hyponatremia. During the course of their illness they were repeatedly admitted to different hospitals and received intravenous fluids, but the correct diagnosis was not reached. Diagnosis was made by stool examination at our hospital when eggs and larvae were detected in stool samples. Although a diagnosis was promptly made, the older sister who suffered from pneumonia and septic shock unfortunately died a few days after admission. The younger sister was treated successfully with albendazole 200 mg twice daily. Diarrhea abated, pedal edema disappeared, and she started to gain weight.

Capillaria philippinensis is an emerging infection in Egypt. Reports in children are scarce. We report here two sisters with C. philippinensis infection, aged 8 and 12 years. Their father was a fisherman and they had a habit of picking small pieces of uncooked fish to eat while their mother prepared their meals. They came from El-Menia governorate, which lies in the northern part of Upper Egypt. Most reported cases from Egypt come from this governorate and nearby areas. Both sisters had persistent profuse watery diarrhea of 12 months' duration. Their weights were below the 5th percentile for age. Both were hypoalbuminemic, but only the younger had pedal edema. Both had hypokalemia and hyponatremia. During the course of their illness they were repeatedly admitted to different hospitals and received intravenous fluids, but the correct diagnosis was not reached. Diagnosis was made by stool examination at our hospital when eggs and larvae were detected in stool samples. Although a diagnosis was promptly made, the older sister who suffered from pneumonia and septic shock unfortunately died a few days after admission. The younger sister was treated successfully with albendazole 200 mg twice daily. Diarrhea abated, pedal edema disappeared, and she started to gain weight.

BACKGROUND: Assessment of quality of life is vital inmonitoring response to various treatment measures. Various instruments, which include both generic and disease-specific instruments, are used in the assessment of health-related quality of life (HRQOL). In this study, we compare two commonly used generic instruments.

OBJECTIVES: The objective of this study was to compare two generic instruments, the Karnofsky Performance Status Scale and the SF-36 Health Survey in hemodialysis (HD) patients. The study also aims to find out the association (if any) between HRQOL scores using these two scales and various clinical and biochemical parameters.

MATERIALS AND METHODS: Sixty-two maintenance HD patients were recruited after informed consents were obtained. Detailed sociodemographic data was obtained. They were assessed during their regular HD sessions. Serum chemistry (which included serum urea, creatinine, Na+, K+, HCO3-, Ca2+, Po4(2-)), albumin, globulin, total protein and hemoglobin (g/dl) were assessed in all the patients. Adequacy of HD was assessed using second-generation Daugirdais formula. HRQOL was assessed using the Karnofsky and SSF-36 instruments and the scores collated and compared. Data was analyzed using SPSS version 10.

RESULTS: Fifty-five patients completed the study (27 males and 28 females, mean age 40.76 +/- 11.05 years and age range of 20-65 years). There was a significant positive correlation between Karnofsky scores and all eight SF-36 domains, but only physical functioning, social functioning and role limitation due to emotional problems maintained the significance on multiple regression analysis. The serum creatinine and hemoglobin postively correlated with physical function, bodily pain, social functioning and Karnofsky scores. Age of the patients correlated negatively with two SF-36 dimensions (physical functioning and role limitation due to physical fitness) and Karnofsky scores.

CONCLUSION: This study revealed a good correlation between Karnofsky performance status scale and the short-form (SF36) health survey in this Egyptian population. Age, serum creatinine and hemoglobin significantly influence quality of life in this HD patient population.

More than 340 parasitic species infect more than 3 billion people worldwide with varying morbidity and mortality. The Tropics constitute the main reservoir of infection with the highest clinical impact, owing to favorable ecological factors. Acquisition of infection, clinical severity, and outcome of a parasitic disease depend on innate and acquired host immunity as well as the parasite's own immune response against the host when infection is established. Organ transplant recipients may acquire significant parasitic disease in 3 ways: transmission with the graft, de novo infection, or activation of dormant infection as a consequence of immunosuppression. Malaria, Trypanosoma, Toxoplasma, and Leishmania are the principal parasites that may be transmitted with bone marrow, kidney, or liver homografts, and microsporidia with xenotransplants. De novo infection with malaria and kala-azar may occur in immunocompromised travelers visiting in endemic areas, while immunocompromised natives are subject to superinfection with different strains of endemic parasites, reinfection with schistosomiasis, or rarely, with primary infections such as acanthamoeba. The list of parasites that may be reactivated in the immunocompromised host includes giardiasis, balantidiasis, strongyloidiasis, capillariasis, malaria, Chagas' disease, and kalaazar. The broad clinical syndromes of parasitic infection in transplant recipients include prolonged pyrexia, lower gastrointestinal symptoms, bronchopneumonia, and meningoencephalitis. Specific syndromes include the hematologic manifestations of malaria, myocarditis in Chagas' disease, acute renal failure in malaria and leishmaniasis, and the typical skin lesions of Chagas' and cutaneous leishmaniasis. Many antiparasitic drugs have the potential for gastrointestinal, hepatic, renal, and hematologic toxicity, and may interact with the metabolism of immunosuppressive agents. It is recommended that transplant clinicians have a high index of suspicion of parasitic infections as an important transmission threat, as well as a potential cause of significant posttransplant morbidity.

To derive guidelines for a safer bone marrow transplantation (BMT) policy, we have to study pre-BMT risk factors that may be associated with an increased post-BMT death. Among those factors, the importance of pre-BMT viral hepatitis markers in BMT donors and recipients remains unsettled. In the present study, we have determined the effect of prior donor and recipient cytomegalovirus (CMV), hepatitis B virus (HBV), and hepatitis C virus (HCV) exposure on the incidence of those viral infections after bone marrow transplantation (BMT). The study included 63 patients presented to the BMT unit; 28 of them underwent transplantation and 35 were not transplanted. All serum markers of CMV, HBV, and HCV infections were monitored using ELISA technique, as well as PCR-DNA for CMV, HBV and HCV RT-PCR techniques for HCV. The incidence of active CMV and HCV was 11/28 (39%) and 6/28 (21%) in post-BMT recipients compared to 2/35 (6%) and 2/35 (6%) in the 35 untransplanted patients (P=0.00003 and P=0.05). Whereas active HBV infection was non significantly (P=0.13) higher 3/28 (11%) in the BMT patients in comparison to 1/35 (3%) in untransplanted patients. Ten out of the 19 (53%) of the CMV-seropositive recipients developed CMV reactivation compared to 1/9 (11%) of the CMV-seronegative recipients who developed CMV seroconversion. In addition, 3/8 (38%) of the HBV-seropositive recipients developed HBV reactivation in comparison to 0/20 of the HBV-seronegative recipients. Moreover, 5/13 (39%) of the HCV-seropositive recipients developed HCV reactivation in comparison to 1/16 (6%) of the HCV-seronegative recipients who developed HCV seroconversion. In conclusion, previous exposure to CMV, HBV, and HCV infections in the recipients of BMT patients were found to influence the risk of developing those viral infections.

PURPOSE: To assess the efficacy of lidocaine gel, bupivacaine drops, and benoxinate drops as topical anesthetic agents in cataract surgery.

SETTING: Kasr El-Aini Hospital, Cairo University, Cairo, Egypt.

METHODS: This prospective randomized study comprised 90 patients scheduled for routine cataract extraction. Patients were randomized into 3 groups of 30 each based on which anesthetic agent they received: lidocaine 2% gel, bupivacaine 0.5% drops, or benoxinate 0.4% drops. Subjective pain at application of the agent and intraoperatively was quantified by the patients using a verbal pain score (VPS) scale from 0 to 10. The duration of discomfort at application, duration of surgery, rate of supplemental sub-Tenon's anesthesia, and complications were recorded.

RESULTS: The mean VPS at application was 2.97, 1.53, and 1.03 in the lidocaine, bupivacaine, and benoxinate groups, respectively; the VPS in the lidocaine group was statistically significantly higher than in the other 2 groups (P<.001). The mean duration of pain at application was 25 seconds, 14 seconds, and 6 seconds in the lidocaine, bupivacaine, and benoxinate groups, respectively, and was statistically significantly higher in the lidocaine group (P<.001). The mean VPS during surgery was 1.6, 4.1, and 7.1 in the lidocaine, bupivacaine, and benoxinate groups; the lidocaine group had a statistically significantly lower mean VPS than the other 2 groups (P<.001). The incidence of supplemental sub-Tenon's injection was 3.3%, 10.0%, and 73.3%, respectively, and was statistically significantly lower in the lidocaine and bupivacaine groups than in the benoxinate group (P<.001). The patients' overall satisfaction was statistically significantly higher in the lidocaine and bupivacaine groups than in the benoxinate group (93.3%, 83.3%, and 33.3%, respectively) (P<.001). Three patients in the lidocaine group had corneal haze at the time of surgery, which was not statistically significant (P>.1).

CONCLUSIONS: Lidocaine gel was a better topical anesthetic agent than bupivacaine and benoxinate drops. Bupivacaine drops were effective in providing deep topical anesthesia.

The effect of alpha-tocopherol, simvastatin and both on male fertility in hypercholesterolemic rats was studied. Induction of hypercholesterolemia was done by feeding rats on a diet containing 1% cholesterol for 30 days. Hypercholesterolemic rats were orally given alpha-tocopherol (3 mg kg(-1) BW) or simvastatin (1 mg kg(-1) BW) or both for 65 days. Fertility index, serum testosterone level, sex organs weight, semen analysis and histopathological examination of testes, seminal vesicles and prostate glands were the parameters used to evaluate the reproductive efficiency of rats. In hypercholesterolemic rats (control +ve), there was a marked decrease in fertility index, testicular weight, sperm cell count, and percentages of sperm motility and viability associated with a significant increase in sperm cell abnormalities. Oral administration of either alpha-tocopherol or simvastatin to hypercholesterolemic rats for 65 days significantly improved the fertility index, testicular weight and semen quality. Concomitant administration of alpha-tocopherol and simvastatin to hypercholesterolemic rats markedly increased fertility index and sperm motility and viability associated with a significant reduction of sperm cell abnormalities. Histopathological examination revealed that testes of hypercholesterolemic rats (control +ve) had degenerated, non-functioning and atrophied seminiferous tubules associated with arrest of spermatogenesis. Oral administration of alpha-tocopherol and simvastatin concomitantly to hypercholesterolemic rats resulted in active mature and full functioning seminiferous tubules. In conclusion, concomitant administration of alpha-tocopherol and simvastatin to hypercholesterolemic male rats improved their reproductive efficiency and produced additional protection against reduced fertility induced by hypercholesterolemia.

Fifty stool specimens collected from severe diarrheic patients attending Misr University Hospital, were examined microscopically for protozoan parasites mainly, Cryptosporidium parvum. Stool examination revealed 22 cases with C. parvum, 8 with E. histolytica, 14 with G. intestinalis and six were parasite-free. The results were compared with the established nested PCR assay to detect DNA directly from stool specimens. After the extraction of DNA from stool, a 402-bp fragment of C. parvum DNA was amplified with two 26-mer outer primers. The amplified products, 194-bp DNA fragment, were used for a second run. This study indicated that the used primers are specific for DNA of C. parvum. The PCR detected a total of 28 positives; six of these cases were negative by AF stool examination, which eventually confirmed to be positive by several successive examinations of the stool and/or duodenal aspiration. Microscopy exhibited 78.5% sensitivity and 100% specificity compared to 100% specificity and sensitivity with PCR. Consequently, PCR is more sensitive and easier to interpret but required more hands-on time to perform and is more expensive than microscopy. However, PCR batch analysis reduces the cost considerably.

BACKGROUND: Because the therapeutic options for managing infections in neonates in developing countries are often limited, innovative approaches to preventing infections are needed. Topical therapy with skin barrier-enhancing products may be an effective strategy for improving neonatal outcomes, particularly among preterm, low birth weight infants whose skin barrier is temporarily but critically compromised as a result of immaturity.

METHODS: We tested the impact of topical application of sunflower seed oil 3 times daily to preterm infants <34 weeks gestational age at the Kasr El-Aini neonatal intensive care unit at Cairo University on skin condition, rates of nosocomial infections and mortality.

RESULTS: Treatment with sunflower seed oil (n = 51) resulted in a significant improvement in skin condition (P = 0.037) and a highly significant reduction in the incidence of nosocomial infections (adjusted incidence ratio, 0.46; 95% confidence interval, 0.26-0.81; P = 0.007) compared with infants not receiving topical prophylaxis (n = 52). There were no reported adverse events as a result of topical therapy.

CONCLUSIONS: Given the low cost (approximately .20 dollars for a course of therapy) and technologic simplicity of the intervention and the effect size observed in this study, a clinical trial with increased numbers of subjects is indicated to evaluate the potential of topical therapy to reduce infections and save newborn lives in developing countries.

Two series of poly(ester-urethane) block copolymers were synthesized from bacterial telechelics, hydroxylated poly[(R)-3-hydroxybutyrate] (PHB-diol), as hard segments, and either poly(butylene glycol adipate)-diol (PBA-diol) or poly(diethylene glycol adipate)-diol (PDEGA-diol), as soft segments, using 1,6-hexamethylene diisocyanate as a non-toxic connecting agent. The content of PHB hard segments systematically varied from 10 to 60 wt.%. The synthesized materials were characterized by 1H NMR, GPC, differential scanning calorimetry, thermogravimetric analysis, wide angle X-ray diffraction, and tensile properties. The crystallization characteristics, reflecting the segmented properties of the synthesized copolymers, are discussed. For poly(ester-urethane)s, based on PHB-diol and PBA-diol, with PHB content less than 50 wt.%, both PBA and PHB crystalline phases, were detected. In contrast, in poly(ester-urethane)s, derived from PHB-diol and PDEGA-diol, only one crystalline phase, corresponding to the PHB hard segments, was observed. The thermogravimetric results of the prepared copolymers showed three-step decomposition assigned to the thermal degradation of PHB hard, PBA or PDEGA soft blocks, and urethane linkage, respectively. The tensile properties indicated that the tensile strength and elongation at the break points of poly(ester-urethane)s, derived from PHB and PBA, are greater than those prepared from PHB and PDEGA. The biodegradability was studied in compost-derived culture. The extent of mineralization was dependent on the copolymer composition. At a comparable incubation time, the copolymers containing 50 wt.% PHB were mineralized to an extent similar to that of the PHB homopolymer. © 2003 Elsevier Ltd. All rights reserved.

We evaluated leaf C isotope discrimination as affected by salinity among three Kentucky bluegrass (Poa pratensis L.) cultivars that differ in their salt tolerance. ?Moonlight?, ?NorthStar?, and ?P-105? Kentucky bluegrass (KBG) were grown in solution culture and exposed to salinity levels of 2.0, 5.0, 8.0, 11.0, and 14.0 dS m?1 for 12 wk. All cultivars exhibited increased leaf firing with increasing salinity. However, Moonlight and NorthStar exhibited less leaf firing than P105 at all salinity levels. The salinity levels that caused 25% shoot growth reduction were 4.9 dS m?1 for NorthStar and Moonlight and 4.1 dS m?1 for P105, indicating that Moonlight and NorthStar have better salinity tolerance than P105. When salinity level was in the range of 2.0 to 8.0 dS m?1, Moonlight produced 1.9-fold more root mass than NorthStar, and NorthStar exhibited 3.9-fold more root mass than P105. When salinity exceeded 8.0 dS m?1, NorthStar had similar root mass as Moonlight, and both showed greater root mass than P105. Cultivar P105 had a higher C isotope discrimination (?) than Moonlight and NorthStar under nonsaline conditions (<2 dS m?1) but a lower ? than Moonlight and NorthStar at 11.0 dS m?1 salinity. The great reduction in ? of P105 as salinity increased suggests that salinity induced a greater degree of stomatal resistance that provided less opportunity for discrimination against the heavier isotope. Carbon isotope discrimination may serve as a useful selection criterion in breeding efforts to develop salt tolerant KBG.

Twenty-one microbial preparations recommended for controlling pathogenic fungal strains causing root rot and wilt diseases of faba bean were investigated for antibiosis against several symbiotic and associative diazotrophs adopting a modified agar-plate-inhibition-zone assay. Rhizobium and Bradyrhizobium exhibited a somewhat similar susceptibility to biocontrol agents while associative diazotrophs showed variable responses. Azotobacter, compared to others, was severely inhibited by such bio-candidates. The members of the biofertilizer formulation ‘Biofertan’ did bear mixed cultivation with the majority of biocontrol agents. Among those, Bacillus subtilis was deemed the pioneer. In pot experiments, almost all the antagonists significantly restricted the severity of root rot and wilt diseases besides modifying faba bean seedling stand and improving plant development. This was very obvious with shoot biomass increases of >50%. Moreover, the bioagents successfully recovered the legume establishment, seriously injured due to pathogenic fungal infection. Simultaneous inoculation with Rhizobium and biocontrol agents provided more growth stimulation compared to either when introduced individually. Field-grown faba beans were inoculated with the diazotroph and representatives of biocontrol strains by two different methods, seed coating and over-head soil. Growth parameters determined were the highest when the legume plant was seed-coated by Rhizobium simultaneously over-head soil inoculated with the bacterial bioagents; this was reported with Bacillus subtilis and Pseudomonas aerugenosa. The significance of combined application of biofertilizer and bioagent to ensure cheap, clean and safe farm products is discussed. © 2004 Taylor & Francis Ltd.

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