A single-institution experience with concurrent capecitabine and radiation therapy in gastrointestinal malignancies

PURPOSE

We report our clinical experience with 32 patients receiving concurrent irradiation and capecitabine.

METHODS AND MATERIALS

Medical records of patients with gastrointestinal malignancies treated with radiation and capecitabine therapy were reviewed.

RESULTS

The population consisted of 20 males and 12 females, with a median age of 67.5 years (45-84 years) and adequate hepatic and bone marrow function. Histology was adenocarcinoma in all patients, except two with esophageal squamous carcinoma. Twenty-one patients received the regimen as adjuvant therapy, three received preoperative therapy, and 8 patients received therapy for palliation. The median dose of capecitabine was 1600 mg/m(2)/day (1200-2500 mg/m(2)/day) orally for 5 days per week for the duration of radiation therapy. Thirty patients received a total dose ranging from 45 Gy to 64 Gy over 4-6 weeks. Two previously radiated patients received total doses of 29.9 Gy and 46 Gy. Grade 3/4 toxicities observed were neutropenia in 3 patients and diarrhea, thrombocytopenia, fatigue, and myocardial infarction in 1 patient each. No treatment-related mortality was observed. Twenty of 21 patients (95.2%) who received adjuvant therapy continue to be in complete remission. Four of 11 (36%) evaluable patients demonstrated a response.

CONCLUSION

Concurrent capecitabine and radiation were very well tolerated and warrant further investigation in prospective trials.

Drosophila Chk2 is required for DNA damage-mediated cell cycle arrest and apoptosis

Chk2 is a major target of ataxia telangiectasia-mutated (ATM) and ATM- and Rad3-related (ATR). Germline mutations in Chk2 have been identified in a subset of patients with Li-Fraumeni syndrome, suggesting that Chk2 is a tumor suppressor gene. To investigate the role of Chk2 in multicellular organisms, a Drosophila chk2 (Dmchk2) mutant was generated. Dmchk2 mutants are viable but show defects in maintaining genome stability and are highly sensitive to ionizing radiation. Interestingly, mutating Dmchk2 completely blocks DNA damage-induced apoptosis and partially blocks DNA damage-induced cell cycle arrest. These results indicate that Chk2 protein plays a crucial role in the DNA damage response pathway mediating cell cycle arrest and apoptosis, and that the ATM-Chk2 pathway is likely conserved in Drosophila.

[Effect of folic acid and supplemented with vitamin A and vitamin E on depressing teratogenesis induced by cyclophosphamide]

The effect of folic acid and the combined effect of folic acid(FA) + vitamin A + vitamin E on the prevention of teratogenesis induced by cyclophosphamide during pregnancy were observed. The results showed that cyclophosphamide resulted a decreased weight and length of the fetuses, an increased rate of neural tube defects and a retardation of ossification centers. The neural tube defects rates in the groups with no any supplementation, supplemented with folic acid alone and supplemented with FA + vitamin A + vitamin E were 87.27%, 42.93% and 30.08% respectively(P < 0.01). The supplementation of FA or the combined supplementation resulted also in greater fetal weight and length, increased ossification of supraoccipital bone (P < 0.01). The study suggested that the combined effect of FA, vitamin A and vitamin E was superior to FA alone.

Evaluation of a new hepatitis B triple-antigen vaccine in inadequate responders to current vaccines

In this double-blind, randomized, controlled study, healthcare professionals with a history of inadequate response to currently available single-antigen hepatitis B vaccines confirmed by measuring hepatitis B surface antibody titer before entry to the study were revaccinated with a 20-microg dose either of a novel triple-antigen (S, pre-S1, and pre-S2) recombinant vaccine or of a present single-antigen (S only) vaccine. Hepatitis B surface antibody titers were measured 8 weeks' post revaccination. A total of 925 individuals were randomized and vaccinated, of whom 915 (98.9%) completed the study and were included in the efficacy analysis. A single dose of the new triple-antigen hepatitis B vaccine (Hepacare) produced a successful response in over three quarters of these subjects who had not mounted an adequate response to current vaccines. The antibody response was statistically significantly superior (P =.002) to that after a single dose of current vaccines. An evaluation of the overall response showed that only the triple-antigen vaccine was able to raise the average antibody response (geometric mean titer [GMT]) to over 100 IU/L. The superior effect of the new vaccine was most pronounced in subjects who were previously complete nonresponders to currently available hepatitis B vaccines. Both vaccines were well tolerated and had similar safety profiles. This study demonstrated that in healthcare workers who had responded inadequately to at least a full course of immunization (median, 5 doses), a single 20-microg dose of a new triple-antigen vaccine induced protective antibody level in more vaccinees (P =.002) and increased the average antibody titer (GMT) in those protected successfully to a greater degree (P <.001) than a further attempt with a current vaccine (Engerix-B).

A multi-center controlled study of rapid hepatitis B vaccination using a novel triple antigen recombinant vaccine

Hepatitis B vaccines have been available for 20 years, however, the disease still remains a global problem. Clearly, the protection of at-risk groups could be improved if a more potent vaccine with a shorter vaccination regimen were available. Hepacare is new recombinant vaccine, which contains three of the surface antigens of the HB virus and has higher immunogenicity than present single antigen (HBsAg only) vaccines. This study evaluates the potential for developing seroprotection rapidly and the viability of a 1 month/two dose regimen. A total of 400 adult subjects were vaccinated using either the present accelerated 2 month/three dose regimen of Engerix-B or a 1 month/two dose regimen of a novel triple antigen vaccine (Hepacare). Both vaccines were well tolerated. Four weeks after a single dose, the seroprotective rates for Engerix-B and the triple antigen vaccine were 5 and 17%, respectively. By month 2, 4 weeks after two doses of vaccine, it was 38 and 61%. Finally by month 3, 4 weeks after a third dose of Engerix-B or placebo, respectively, the seroprotection rates were 71 and 82%. The geometric mean titres (GMTs), of these responders was then 119 and 120 IU/l, respectively. Both vaccines were well tolerated. At all points up to and including 3 months after beginning vaccination, the novel 1 month/two dose regimen of Hepacare was significantly more effective in producing seroporotective titres than the 2 month/three dose regimen of Engerix-B (P = 0.001).

Study on detecting antibodies to Toxoplasma gondii in pooled serum of blood donors by Dot-IGSS

To prevent post-transfusion toxoplasmosis, the sera of blood donors, per six of which were mixed as a pool, were examined for anti-Toxoplasma gondii antibiodies by Dot-immunogold silver staining (Dot-IGSS) with the single serum specimens examined simultaneously. The results showed that the sensitivity and specificity of serum pool method were 92.31% and 99.96% respectively. The consistent rate between the two methods was 99.73% and kappa value was 0.947 (p<0.01). Considering the mean infection rate of Toxoplasma gondii being 4.86% in China, if the serum pool method be adoped, with pool size k=5, a 57% reduction in the number of tests, as well as the cost of the screen, can be expected. Beside the social benefit, consequent upon the interruption of the Toxoplasma gondii infection spread through blood transfusion also can be expected.

Adult hepatitis B vaccination using a novel triple antigen recombinant vaccine

Present hepatitis B vaccines use multidose prolonged regimens, which even healthcare workers at risk do not always complete. Moreover, when vaccination is completed there remain some who fail to achieve adequate protection. The protection of adults at risk could be improved if there were a more potent vaccine and/or a shorter vaccination regimen available. Vaccine-naive adults were randomized to vaccination with either Engerix-B (SmithKline Biologicals, Rixensart, Belgium) or a novel triple antigen (S, pre-S1, and pre-S2) recombinant vaccine (Hepacare; Medeva Pharma Plc, Speke, UK). The primary efficacy parameter was the degree of seroprotection 6 or 7 months (26 +/- 2 weeks) after beginning vaccination. A total of 304 adults entered the study. Of these, 16 failed to complete the study (9 on Hepacare and 7 on Engerix-B). With the Engerix-B standard (0, 1, 6) regimen, 88% of subjects were protected by month 7, whereas with the triple antigen vaccine a 2-dose regimen (0, 1) provided equivalent protection (91%) within 6 months and a 3-dose (0, 1, 6) regimen was significantly superior (98% seroprotected by 7 months after starting vaccination P <.001). With adults at risk for a suboptimal response (i.e., older adults, the obese, men, and smokers) the triple antigen vaccine produced a greater degree of protection. The vaccines had similar safety profiles. Both vaccines were well tolerated. In healthy normal adults, a triple antigen hepatitis B vaccine containing S and pre-S antigens produced an enhanced immunologic response and was as effective as a 2- and 3-dose regimen.

Phase II evaluation of paclitaxel, alpha-interferon, and cis-retinoic acid in advanced renal cell carcinoma

BACKGROUND

Interferon and 13-cis-retinoic acid (13-CRA) therapy showed clinical response rates of 30% in advanced renal cell carcinoma (RCC). This combination also enhanced sensitivity to paclitaxel in a bcl-2 and mutant p53 expressing renal carcinoma cell line. Based on this, the authors conducted a Phase II clinical trial of the combination of interferon, 13-CRA, and weekly paclitaxel, in advanced RCC.

METHODS

The eligibility criteria consisted of unresectable or metastatic RCC, measurable disease, a Southwest Oncology Group performance status of 0-2, and adequate bone marrow, hepatic, and renal function. Prior cytotoxic or immunologic treatment including interferon was permitted. Paclitaxel was administered at a dose of 80 mg/m(2) as a 1-hour intravenous infusion on Days 1, 8, and 15 of each 28-day cycle. Interferon was administered at a dose of 3 million units subcutaneously daily and 13-CRA at 1 mg/kg/day orally in 2 divided doses for the first 21 days of each cycle.

RESULTS

Twenty-one patients were enrolled with a median age of 52 years, 16 males and 5 females, 10 patients with no prior therapy, 5 each with prior interleukin-2 or interferon therapy, and 1 patient with both. Four patients had also received prior investigational chemotherapy. A total of 61 cycles were administered with a median of 2 per patient. Grade 3 and 4 toxicities were neutropenia in three patients, anemia in four patients, and asthenia, skin rash, and hypersensitivity reaction in one case each. Of the 20 evaluable patients, one objective partial response was observed for a duration of 7+ months. Seven patients had disease stabilization. The median survival of the entire population was 9.5 months (range, 4-18+ months).

CONCLUSIONS

The combination of 13-CRA, interferon, and weekly paclitaxel was well tolerated and had minimal efficacy in advanced RCC.

Confirmation of susceptibility gene loci on chromosome 1 in northern China Han families with type 2 diabetes

OBJECTIVE

To confirm previous effort to identify type 2 diabetes susceptibility genes in a Northern Chinese population by conducting a new genome scan with both an increased number of type 2 diabetes families and a new set of microsatellite markers within the previously localized regions.

METHODS

A genome scan method was applied. After multiplexed PCR, electrophoreses, genescan and genotyping analysis, we obtained size information for all loci, and then a further study was done by both parametric and non-parametric linkage analysis to investigate the P values and Z values of these loci.

RESULTS

We surveyed 34 microsatellite markers which distributed within 5 regions along chromosome 1, and a total of 12,000 genotypes were screened. Evidence of linkage with diabetes was identified for 8 of the 34 loci. All P values of the 8 loci were lower than 0.05, and the highest Z value was 2.17. A very interesting finding is that all 5 markers at the p- terminal 1p36.3-1p36.23 region, spanning a long range of 16.9 cM, were identified to have a low P value of less than 0.05, which suggests that this region may contain multiple susceptibility genes. Regions 4 and 5 also confirmed the previous findings, and we narrowed these two regions to a 2.7 cM and 2.5 cM regions, respectively.

CONCLUSIONS

We further confirmed the results gained in the previous genome-wide scan using an increased number of NIDDM families and a new set of microsatellite markers lying within the initially localized regions. The fact that all 5 loci at the p- terminal region displayed a low P value of less than 0.05 suggests that more than 1 susceptibility gene may reside in this region.

The p38 mitogen-activated protein kinase is involved in associative learning in rabbits

This study examined the role of the mitogen-activated protein kinase (MAPK) family during acquisition of the rabbit's classically conditioned eye-blink response. Eye-blink conditioning produced a significant, bilateral activation of both extracellular signal-regulated protein kinases (ERKs) and p38 MAPK in the anterior cerebellar vermis. There was also a significant bilateral activation of ERKs in the dorsal hippocampus with no change in p38 MAPK. These changes were seen at 2 min after the last conditioning session, were maintained for at least 180 min, and occurred without any change in the protein expression of either ERKs or p38 MAPK. There were no changes in ERKs or p38 MAPK in frontal cortex, in cerebellar hemispheral lobule VI, or in a section of brainstem containing the inferior olive. Moreover, the stress-related protein kinase Jun N-terminal kinase (JNK), another subfamily of MAPKs, was not altered in any of the brain regions examined. Animals receiving explicitly unpaired presentations of a conditioned stimulus and an unconditioned stimulus did not acquire conditioned responses (CRs) and did not demonstrate any changes in ERKs, p38 MAPK, or JNK. The intraventricular injection of SB203580, a selective p38 MAPK inhibitor, significantly retarded CR acquisition and blocked the learning-related increases in p38 MAPK activity in the anterior vermis. PD98059, a selective MAPK kinase inhibitor, had a smaller and only marginally significant effect on CR acquisition, although it did block the learning-related increases in ERK activity in both the hippocampus and anterior vermis. These results indicate that p38 MAPK is activated during associative learning and may play a role in the transcriptional events that lead to memory consolidation.

Outpatient biochemotherapy with interleukin-2 and interferon alfa-2b in patients with metastatic malignant melanoma: results of two phase II cytokine working group trials

PURPOSE

The Cytokine Working Group performed a randomized phase II trial of two outpatient biochemotherapy regimens to identify an outpatient regimen with high antitumor activity and less toxicity than inpatient regimens which might be compared with chemotherapy or inpatient biochemotherapy regimens in future phase III trials.

PATIENTS AND METHODS

Eighty-one patients with metastatic malignant melanoma received dacarbazine 250 mg/m(2)/d intravenously (IV) and cisplatin 25 mg/m(2)/d IV on days 1, 2, and 3, plus interferon (IFN) alfa-2b 5 mU/m(2) subcutaneously (SC) on days 6, 8, 10, 13, and 15, given every 28 days. Interleukin-2 (IL-2) was given daily on days 6 to 10 and 13 to 15. In group 1, IV IL-2 was given at 18.0 MU/m(2), and in group 2, SC IL-2 was given at 5.0 mU/m(2).

RESULTS

In group 1 (IV IL-2), there were five complete responses (CRs) and 11 partial responses (PRs) among 44 patients (objective response rate [ORR], 36%; 95% confidence interval [CI], 22% to 51%). In group 2 (SC IL-2), there was one CR and five PRs among the 36 patients (ORR, 17%; 95% CI, 4% to 29%). The median survival was 10.7 months in group 1 and 7.3 months in group 2. Eleven patients in group 1 and four patients in group 2 remain alive as of the last follow-up. Toxicities in both groups were similar. No patient required hospitalization for neutropenic fever.

CONCLUSION

Biochemotherapy has activity in these outpatient regimens with acceptable toxicity. The antitumor activity observed with the IV IL-2 regimen seems similar to that of inpatient biochemotherapy regimens. If inpatient biochemotherapy regimens develop an established role in the management of melanoma, future phase III trial comparisons with this outpatient IV IL-2 regimen would be appropriate.

Comparison of a triple antigen and a single antigen recombinant vaccine for adult hepatitis B vaccination

Hepatitis B and its sequelae are a major public health problem. Vaccines have been available for almost 20 years; however the disease still remains a global problem. Many factors contribute to the failure to control hepatitis B, including the limited nature of the vaccination programs implemented initially. Only relatively recently has mass childhood vaccination begun to be implemented and vaccination of high-risk groups, other than healthcare workers, is still not general policy. Additional factors contributing to continued persistence of hepatitis B in the developed world are that the present vaccines are not fully used by those recommended to be vaccinated and even when vaccination is carried out appropriately, there remain some who fail to achieve adequate protection. Clearly, the protection of at-risk groups who have inadequate response to current vaccines, and those who are unwilling or unable to comply with protracted multi-dose vaccine regimens, could be improved if there were a more potent vaccine and/or a shorter vaccination regimen available. Adults who had never been vaccinated against hepatitis B were randomised to receive a vaccination course of either a present single antigen (S) vaccine (Recombivax-HB) or a novel triple antigen (S, pre-S1, and pre-S2) recombinant vaccine (Hepacare Medeva Pharma plc). Doses were given at baseline and 1 month and 6 months later. Hepatitis B surface antibody (anti-HBs) levels were measured at 2, 4, 6, and 7 months after beginning vaccination. The primary efficacy parameter was the degree of protection, measured as the percentage of subjects with anti-HBs titres > or = 10 IU/L, 6 or 7 months (26 +/- 2 weeks) after beginning vaccination. A total of 303 adult subjects entered the study and were vaccinated. Of these, 11 failed to complete the study (4 on Hepacare and 7 on Recombivax-HB); however all but 2 (1 to receive the triple antigen vaccine and 1 to receive Recombivax-HB) were included in the intent-to-treat population for efficacy evaluation. Treatment randomisation was stratified at entry based on age (above and below 40 years old) and gender. The standard three-dose/6-month vaccination regimen of the single antigen vaccine protected 83% of subjects by 7 months after starting vaccination whereas the triple antigen vaccine as a two-dose/1-month regimen protected 88% within 6 months and as a three-dose/6-month regimen protected 97% by 7 months after starting vaccination. Thus the protection rate provided by the shortened (0, 1) regimen of the novel vaccine was "essentially equivalent" (i.e., not statistically inferior) to that provided by the full (0, 1, and 6) regimen of today's vaccine (88% vs. 81%, P < 0.001), and the protection rate provided by a three-dose/6-month (0, 1, and 6) regimen of the new vaccine was significantly superior to that provided by present vaccines (97% vs. 83% P < 0.001). The percentage of subjects protected increases with time after beginning vaccination and at all time points up to and including 6 months was significantly greater with the two-dose regimen of the triple antigen vaccine than with the single antigen vaccine regimen. In adults at risk for a reduced response to hepatitis B vaccination [i.e., older adults (>/=40), the obese, males, and smokers], the triple antigen vaccine produced a significantly greater percentage of protected subjects (P < 0.001) and higher geometric mean titre (P < 0.001). Indeed as a three-dose/6 month regimen, the triple antigen vaccine raised the level of protection in these vulnerable subgroups to that seen when a single antigen vaccine is used in the optimal younger adult group. Both vaccines were well tolerated and had similar safety profiles. The most frequently (> or = 10%) reported adverse events with the use of either vaccine were pain at the site of injection (38% vs. 41% vs. 20% for the two-dose Hepacare regimen, the three-dose Hepacare regimen, and the three-dose Recombivax-HB regimen, respectively), infections at the site of injection (1% vs. 14% vs. 9%), headache (9% vs. 13% vs. 11%), and nausea (7% vs. 11% vs. 3%). It is concluded that in healthy normal adults, a triple antigen hepatitis B vaccine that contained S and pre-S antigens produced an enhanced immunological response. This was exemplified by the novel vaccine's ability to overcome factors such as advancing age (> or = 40 years), obesity, and smoking, each of which is known to reduce the potential for protection with present recombinant S only vaccines. A two-dose/1-month (0 and 1) regimen of this triple antigen vaccine was as effective as the standard three-dose/6 month (0, 1, and 6) regimen of present single antigen vaccines. (c) 2001 Wiley-Liss, Inc.

[Ethyl acetate synthesis on-line measurement by Raman spectroscopy]

We report an on-line Raman spectroscopy measurement with fiber probe. In the experiment, the real-time spectrum measurement of ethyl acetate synthesis reaction with ethanol and acetic acid was carried out by using a homemade Raman spectrometer. The time variation of integrated spectrum peak intensities of reaction product and raw materials are obtained. From the integrated peak intensities, the concentrations of the reactants can be deduced and the ending point of reaction under this experimental condition can be determined.

Combination paclitaxel, carboplatin, and gemcitabine is an active treatment for advanced urothelial cancer

PURPOSE

To determine the efficacy and toxicity of the drug combination of carboplatin, paclitaxel, and gemcitabine in patients with advanced urothelial carcinoma.

PATIENTS AND METHODS

Patients eligible included those with advanced urothelial malignancy of any histology, no previous chemotherapy for metastatic disease, Southwest Oncology Group performance status of 2 or less, serum creatinine levels of 2 mg/dL or less, and adequate bone marrow and hepatic function. Treatment consisted of paclitaxel 200 mg/m2, carboplatin (target area under the curve = 5) on day 1, and gemcitabine 800 mg/m2 on days 1 and 8, repeated every 21 days.

RESULTS

Forty-nine patients (44 men and five women) were enrolled; the patients' median age was 63 years, and their median creatinine clearance was 78 mL/min (range, 26 to 165 mL/min). Forty-three patients had transitional cell carcinoma, and six had squamous cell carcinoma or mixed histology. Ten patients had metastases to lymph nodes only, six had locally advanced disease, four had locally recurrent disease, 24 patients had visceral metastases, and five had soft tissue metastases. Twenty-one patients had disease in one site, 16 in two sites, and 12 in three sites. A total of 272 cycles were administered (median, six cycles; range, 1 to 15 cycles). Major toxicities were grade 3 and 4 neutropenia in 17 and 19 patients, respectively; grade 3 and 4 thrombocytopenia in 15 and six patients, respectively; grade 3 and 4 anemia in 10 and two patients, respectively; grade 3 neuropathy in four patients; and diarrhea in two patients. The incidence of febrile neutropenia was 1.4%; no patients died of drug toxicity. Forty-seven of the 49 patients were assessable for response. Fifteen (32%) patients experienced a complete response, and 17 (36%) patients experienced a partial response (32 of 47 patients, 68%; 95% confidence interval, 56.27 to 82.86). Responses were seen in all sites, including 15 (68%) of 22 patients with visceral metastases. The median survival was 14.7 months, with a 1-year survival of 59%.

CONCLUSION

Combination paclitaxel, carboplatin, and gemcitabine is active; an encouraging number of patients with advanced urothelial carcinoma treated with this regimen experienced complete remission.

DNA replication control through interaction of E2F-RB and the origin recognition complex

The E2F transcription factor and retinoblastoma protein control cell-cycle progression and DNA replication during S phase. Mutations in the Drosophila dE2F1 and dDP genes affect the origin recognition complex (DmORC) and initiation of replication at the chorion gene replication origin. Here we show that mutants of Rbf (an retinoblastoma protein homologue) fail to limit DNA replication. We also show that the dDP, dE2F1 and Rbf proteins are located in a complex with DmORC, and that dE2F1 and DmORC are bound to the chorion origin of replication in vivo. Our results indicate that dE2F1 and Rbf function together at replication origins to limit DNA replication through interactions with DmORC.

The cascade radical annulation approach to new analogues of camptothecins. Combinatorial synthesis of silatecans and homosilatecans

An overview of the cascade radical annulation approach to the camptothecin family of antitumor drugs is presented. This combinatorial synthetic approach involves two key steps: (1) N-propargylation of a lactone/pyridone D/E ring fragment and (2) cascade radical annulation of an A-ring isonitrile to form rings B and C. The synthesis is probably the most flexible and general route to the camptothecin class of molecules. The parallel synthesis of several libraries of silatecan and homosilatecan libraries is summarized. One of the first-generation silatecans, DB-67, is emerging as a serious candidate for cancer chemotherapy.

[FTIR studies on two compounds containing cyanide]

Two compounds containing cyanide [Ni(1,10-phen)2O2MoS2(CuCN)]n and [ZnCu4 (CN)6(dmf)4]n have been synthesized. The FTIR spectra and the crystal structure of those clusters have also been deal with. The stretching frequency of cyanide is alterable with the different coordinated environments.

Surgical outcomes after breast cancer surgery: measuring acute lymphedema

BACKGROUND

Studies of lymphedema have used inconsistent measures and criteria. The purpose of this pilot study was to measure the onset and incidence of acute lymphedema in breast cancer survivors using strict criteria for limb evaluation.

MATERIALS AND METHODS

Eligible women were those undergoing breast cancer surgery that included axillary staging and/or radiation therapy of the breast. Arm volume, strength, and flexibility were measured preoperatively and quarterly. Lymphedema was defined as a greater than 10% increase in limb volume. Additional strength and flexibility assessments were done at these times.

RESULTS

In 30 evaluable patients, half underwent modified radical mastectomy and half lumpectomy, with half of the lumpectomy patients undergoing axillary node staging. Of the 30 patients 27% were Stage 0; the rest were Stage I (27%), IIA (13%), IIB (23%), and IIIA (7%). One subject was IIIB postoperatively. There were 2 women with a 10% or greater change in limb volume; the change was detected in one woman at 3 months (5% incidence) and in the second woman at 6 months (11% incidence). Both had undergone mastectomy and axillary dissection and one of these two women had symptoms of tingling and numbness in the affected arm that began at 3 months. Overall, 35% of the sample experienced symptoms by 3 months, which included numbness, aching, and tingling of the entire upper extremity, but without volume changes. The relationship between undergoing modified radical mastectomy and experiencing symptoms in the affected limb at 3 months was significant (P = 0.05).

CONCLUSIONS

In this interim report strict methods of measurement and limb volume comparisons detected acute lymphedema at 3 months in 5% of the sample, and at 6 months in 11% of the sample. Furthermore, symptoms were detected in 35% without volume changes at 3 months postoperatively, which may warn of lymphedema occurrence within the next 3 months. This may assist clinical evaluation of symptoms in the postoperative period and support early referral to lymphedema experts.

[FTIR studies of compounds of 2-D networks]

Recently, there is increasing interest in the study of 2-D square network materials which have inner cavities as zeolites, expected to find applications in catalysis, sensor and absorbent. Here, the synthesis of two compounds of [[Cd(4,4'-bpy)2.2H2O](NO3)2.4H2O] and [[Cd(4,4'-bpy)2NO3H2O].NO3.(C13H11NO)2] have been reported. The FTIR spectra of those clusters and the structure-sensitive bands are studied.

Effects of prenatal exposure to cocaine on the developing brain: anatomical, chemical, physiological and behavioral consequences

Earlier studies of human infants and studies employing animal models had indicated that prenatal exposure to cocaine produced developmental changes in the behavior of the offspring. The present paper reports on the results obtained in a rabbit model of in utero exposure to cocaine using intravenous injections (4 mg/kg, twice daily) that mimic the pharmacokinetics of crack cocaine in humans. At this dose, cocaine had no effect on the body weight gain of dams, time to delivery, litter size and body weight or other physical characteristics of the offspring. In spite of an otherwise normal appearance, cocaine-exposed neonates displayed a permanent impairment in signal transduction via the D1 dopamine receptor in caudate nucleus, frontal cortex and cingulate cortex due to an uncoupling of the receptor from its associated Gs protein. This uncoupling in the caudate nucleus was shown to have behavioral consequences in that young or adult rabbits, exposed to cocaine in utero, failed to demonstrate amphetamine-elicited motor responses normally seen after activation of D1 receptors in the caudate. The cocaine progeny also demonstrated permanent morphological abnormalities in the anterior cingulate cortex due to uncoupling of the D1 receptor and the consequent inability of dopamine to regulate neurite outgrowth during neuronal development. Consistent with the known functions of the anterior cingulate cortex, adult cocaine progeny demonstrated deficits in attentional processes. This was reflected by impairment in discrimination learning during classical conditioning that was due to an inability to ignore salient stimuli even when these were not relevant to the task. The impairment in discrimination learning also occurred in an instrumental avoidance task and could be shown to be due to an impairment of cingulothalamic learning-related neuronal coding. It was proposed that the selective loss of D1-related neurotransmission in the anterior cingulate cortex prevented an appropriate activation of GABA neurons and thus a loss of inhibitory regulation that is necessary for processes involved in associative attention. Taken together, these findings suggest that the uncoupling of the D1 receptor from its G protein may be the fundamental source of the anatomic, cognitive and motor disturbances seen in rabbits exposed to cocaine in utero. Moreover, the long-term cognitive and motor deficits observed in the rabbit model are in agreement with the recent reports indicating that persistent attentional and other behavioral deficits may be evident in cocaine-exposed children as they grow older and are challenged to master more complex cognitive tasks.

Cost analysis of pancreatic carcinoma treatment

BACKGROUND

Pancreatic carcinoma is a major health issue and financial burden to society. To improve the quality and efficiency of care delivered, it is essential for health care providers to have a good understanding of the cost of treatment.

METHODS

The authors examined the facility-based costs and survival of 103 patients with pancreatic carcinoma who were treated at the Karmanos Cancer Institute between January 1992 and September 1998. Longitudinal cost data for each patient were obtained, and from those data, 6-month, 1-year, and lifetime total treatment costs were calculated.

RESULTS

The average 6-month, 1-year, and lifetime total treatment costs were $37,327, $42,218, and $48,803, respectively, and the median survival was 7 months. In univariate analyses, the disease stage at diagnosis was a highly significant predictor of total cost. Patients with metastatic disease had the lowest cost, and patients with resectable disease had the highest cost. In multivariate analyses controlling for disease stage, treatment strategies and dual insurance coverage were also important predictors of costs but patient age, race, and gender were not predictive. Disease stage also was highly predictive of survival. In a multivariate analysis controlling for disease stage, chemotherapy and radiation therapy were correlated with longer survival, whereas resection and palliative bypass surgery were not.

CONCLUSIONS

The costs of treating patients with pancreatic carcinoma are considerable, even though survival duration typically is short. Disease stage was the most dominating factor determining costs and survival. After controlling for disease stage, chemotherapy, surgery, and dual insurance coverage were also significantly associated with higher cost of care. However, in survival analyses, only chemotherapy and radiation therapy were associated with a significant increase in patient survival.

Phase II study of dolastatin-10 in patients with hormone-refractory metastatic prostate adenocarcinoma

Dolastatin-10 is a natural, cytotoxic peptide with microtubule-inhibitory and apoptotic effects. It has demonstrated in vitro and in vivo efficacy in the DU-145 human prostate cancer model. A Phase II clinical trial was designed in patients with hormone-refractory prostate cancer. Dolastatin-10 was administered at a dose of 400 microg/m2 i.v. every 3 weeks. Dose escalation to 450 microg/m2 was permitted. Toxicity evaluation was conducted every 2 weeks, and assessment of response was done at the end of every two cycles. Sixteen patients were enrolled between October 1998 to December 1999. The median age was 71 years (range, 59-79 years). Median prostate-specific antigen value was 108 ng/ml (range, 15.3-1672 ng/ml). Of the 15 eligible patients, 7 were Caucasian and 8 were African-American. Eight patients had bone-only metastases, and seven had measurable disease with or without bone metastases. A total of 56 cycles have been administered. Only 2 patients required dose adjustment because of toxicity, and in 5 patients, dose escalation was feasible to 450 microg/m2. The major toxicities observed were grade 3 and 4 neutropenia in 8 patients and grade 3 neuropathy in 1 patient. All 15 patients are evaluable for response. Three patients demonstrated stable disease; 2 of these had bone disease, and 1 had nodal metastasis. All others had disease progression. Dolastatin-10 is very well tolerated in this elderly, pretreated population but lacks significant clinical activity as a single agent.

Ssn6-Tup1 interacts with class I histone deacetylases required for repression

Ssn6-Tup1 regulates multiple genes in yeast, providing a paradigm for corepressor functions. Tup1 interacts directly with histones H3 and H4, and mutation of these histones synergistically compromises Ssn6-Tup1-mediated repression. In vitro, Tup1 interacts preferentially with underacetylated isoforms of H3 and H4, suggesting that histone acetylation may modulate Tup1 functions in vivo. Here we report that histone hyperacetylation caused by combined mutations in genes encoding the histone deacetylases (HDACs) Rpd3, Hos1, and Hos2 abolishes Ssn6-Tup1 repression. Unlike HDAC mutations that do not affect repression, this combination of mutations causes concomitant hyperacetylation of both H3 and H4. Strikingly, two of these class I HDACs interact physically with Ssn6-Tup1. These findings suggest that Ssn6-Tup1 actively recruits deacetylase activities to deacetylate adjacent nucleosomes and promote Tup1-histone interactions.

The novel silatecan 7-tert-butyldimethylsilyl-10-hydroxycamptothecin displays high lipophilicity, improved human blood stability, and potent anticancer activity

We describe the rational design and synthesis of B- and A, B-ring-modified camptothecins. The key alpha-hydroxy-delta-lactone pharmacophore in 7-tert-butyldimethylsilyl-10-hydroxycamptothecin (DB-67, 14) displays superior stability in human blood when compared with clinically relevant camptothecin analogues. In human blood 14 displayed a t(1/2) of 130 min and a percent lactone at equilibrium value of 30%. The tert-butyldimethylsilyl group renders the new agent 25-times more lipophilic than camptothecin, and 14 is readily incorporated, as its active lactone form, into cellular and liposomal bilayers. In addition, the dual 7-alkylsilyl and 10-hydroxy substitution in 14 enhances drug stability in the presence of human serum albumin. Thus, the net lipophilicity and the altered human serum albumin interactions together function to promote the enhanced blood stability. In vitro cytotoxicity assays using multiple different cell lines derived from eight distinct tumor types indicate that 14 is of comparable potency to camptothecin and 10-hydroxycamptothecin, as well as the FDA-approved camptothecin analogues topotecan and CPT-11. In addition, cell-free cleavage assays reveal that 14 is highly active and forms more stable top1 cleavage complexes than camptothecin or SN-38. The impressive blood stability and cytotoxicity profiles for 14 strongly suggest that it is an excellent candidate for additional in vivo pharmacological and efficacy studies.

The c-Myc-interacting adaptor protein Bin1 activates a caspase-independent cell death program

Cell death processes are progressively inactivated during malignant development, in part by loss of tumor suppressors that can promote cell death. The Bin1 gene encodes a nucleocytosolic adaptor protein with tumor suppressor properties, initially identified through its ability to interact with and inhibit malignant transformation by c-Myc and other oncogenes. Bin1 is frequently missing or functionally inactivated in breast and prostate cancers and in melanoma. In this study, we show that Bin1 engages a caspase-independent cell death process similar to type II apoptosis, characterized by cell shrinkage, substratum detachment, vacuolated cytoplasm, and DNA degradation. Cell death induction was relieved by mutation of the BAR domain, a putative effector domain, or by a missplicing event that occurs in melanoma and inactivates suppressor activity. Cells in all phases of the cell cycle were susceptible to death and p53 and Rb were dispensable. Notably, Bin1 did not activate caspases and the broad spectrum caspase inhibitor ZVAD.fmk did not block cell death. Consistent with the lack of caspase involvement, dying cells lacked nucleosomal DNA cleavage and nuclear lamina degradation. Moreover, neither Bcl-2 or dominant inhibition of the Fas pathway had any effect. In previous work, we showed that Bin1 could not suppress cell transformation by SV40 large T antigen. Consistent with this finding, we observed that T antigen suppressed the death program engaged by Bin1. This observation was interesting in light of emerging evidence that T antigen has roles in cell immortalization and human cell transformation beyond Rb and p53 inactivation. In support of a link to c-Myc-induced death processes, AEBSF, a serine protease inhibitor that inhibits apoptosis by c-Myc, potently suppressed DNA degradation by Bin1. Our findings suggest that the tumor suppressor activity of Bin1 reflects engagement of a unique cell death program. We propose that loss of Bin1 may promote malignancy by blunting death penalties associated with oncogene activation.

Can endothelial seeding enhance patency and inhibit neointimal hyperplasia? Experimental studies and clinical trial of endothelial seeded venous prostheses

BACKGROUND

Venous prostheses have poor long-term patency; to improve this situation, experimental studies have been carried out.

METHODS

Methods of endothelial cell harvesting, prosthetic seeding and implantation mainly in the inferior vena cava were studied in 127 dogs. Evaluations were conducted by angiography, gross appearance, light, scanning and transmission electron microscopic observations, histo-fluorescent staining, as well as radioimmunoassay.

RESULTS

It was found that at five to ten days following implantation, the prosthetic endothelialisation could be reliably achieved in the seeded group and a 100% patency of the seeded inferior vena caval prostheses was attained at 100 days. The thickness of the neointima in the seeded group at 10 and 100 days was 299 microm and 302 microm, respectively. The metabolite of PGI2 from extrinsic arachidonic acid, 6-keto PGF1a, produced by cells from seeded graft was significantly higher than that from spontaneously formed cells and the reverse found with thromboxane B2. A temporary (one week) distal (femoral) arteriovenous fistula enhanced graft patency. These results indicated that the early endothelialisation of grafts by seeding enhanced the patency and inhibited intimal hyperplasia of venous prostheses. The clinical outcome was impressively improved from our previous experience with ten of eleven venous grafts patent over a follow-up period of six to nine years. These might result from the realization of early endothelialisation and its cells derived from seeding being able to produce significantly more PGI2 and less thromboxane B2.

CONCLUSIONS

The endothelial cell seeding technique may bring us much closer to an ideal venous prosthesis.

Drosophila Cdk4 is required for normal growth and is dispensable for cell cycle progression

Complexes of D-type cyclins and cdk4 or 6 are thought to govern progression through the G(1) phase of the cell cycle. In Drosophila, single genes for Cyclin D and Cdk4 have been identified, simplifying genetic analysis. Here, we show that Drosophila Cdk4 interacts with Cyclin D and the Rb homolog RBF as expected, but is not absolutely essential. Flies homozygous for null mutations develop to the adult stage and are fertile, although only to a very limited degree. Overexpression of inactive mutant Cdk4, which is able to bind Cyclin D, does not enhance the Cdk4 mutant phenotype, confirming the absence of additional Cyclin D-dependent cdks. Our results indicate, therefore, that progression into and through the cell cycle can occur in the absence of Cdk4. However, the growth of cells and of the organism is reduced in Cdk4 mutants, indicating a role of D-type cyclin-dependent protein kinases in the modulation of growth rates.

Functional parathyroid hormone receptors are present in an umbilical vein endothelial cell line

Acute parathyroid hormone exposure induces vascular smooth muscle relaxation. In contrast, continuous infusion of parathyroid hormone leads to vasoconstriction and an elevation of blood pressure. Despite the known effects of parathyroid hormone on vascular smooth muscle, possible direct effects on the vascular endothelium have not previously been investigated. Using a human umbilical vein endothelial cell line, we found that parathyroid hormone increased both intracellular calcium and cellular cAMP content in these endothelial cells. Furthermore, exposure of these cells to increasing concentrations of parathyroid hormone stimulated both [(3)H]thymidine incorporation and endothelin-1 secretion. Parathyroid hormone/parathyroid hormone-related peptide receptor mRNA could be detected at low levels in these cells. In summary, these data demonstrate that endothelium-derived cells contain functional parathyroid hormone receptors. The potential physiological role of these receptors remains to be determined.

Synergistic inhibitor binding to Streptococcus pneumoniae 5-enolpyruvylshikimate-3-phosphate synthase with both monovalent cations and substrate

The inhibitor binding synergy mechanism of the bi-substrate enzyme Streptococcus pneumoniae 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) has been investigated with a linkage thermodynamics strategy, involving direct binding experiments of one ligand conducted over a range of concentration of the other. The results demonstrate that binding of the inhibitor glyphosate (GLP) is highly synergistic with both a natural substrate shikimate-3-phosphate (S3P) and activating monovalent cations. The synergy between GLP and S3P binding was determined to be 1600-fold and is in qualitative agreement with previous work on Escherichia coli EPSPS. The binding molar ratios of S3P and GLP were measured as 1.0 and 0.7 per EPSPS, respectively. Monovalent cations that have been shown previously to stimulate S. pneumoniae EPSPS catalytic activity and its inhibition by GLP were found here to exhibit a similar rank-order with respect to their measured GLP binding synergies (ranging from 0 to > or =3000-fold increase in GLP affinity). The cation specificity and the sub-millimolar concentrations where these effects occur strongly suggest the presence of a specific cation binding site. Analytical ultracentrifugation data ruled out GLP-binding synergy mechanisms that derive from, or are influenced by, changes in oligomerization of S. pneumoniae EPSPS. Rather, the data are most consistent with an allosteric mechanism involving changes in tertiary structure. The results provide a quantitative framework for understanding the inhibitor binding synergies in S. pneumoniae EPSPS and implicate the presence of a specific cation binding regulatory site. The findings will help to guide rational design of novel antibiotics targeting bacterial EPSPS enzymes.

Cisplatin, cytarabine, caffeine, and continuously infused 5-fluorouracil (PACE) in the treatment of advanced pancreatic carcinoma: a phase II study

Encouraging results using cisplatin, cytarabine, and caffeine for the treatment of pancreatic carcinoma prompted a phase II study using these agents and adding continuous intravenous infusion (CI) 5-fluorouracil (5-FU) (PACE). Patients with advanced pancreatic adenocarcinoma who had not received prior cytotoxic therapy were eligible. Treatment consisted of the following: on day 1, the administration of cisplatin 100 mg/m2 IV, cytarabine 2 g/m2 IV every 12 hours x 2 doses, and caffeine 400 mg/m2 subcutaneously after each cytarabine dose; and on days 3 to 21, 5-FU 250 mg/m2/day given by CI. Cycles were repeated every 28 days. Thirty eligible patients were entered in the study. The median number of cycles received was three. Grade IV neutropenia and thrombocytopenia occurred in 53% and 27% of patients, respectively. Among 30 treated patients, complete remission (CR) was seen in 2 patients and partial remission (PR) in 3 patients, for an overall response rate of 16.7% (95% confidence interval 6.8-32.4%). The median survival was 5.0 months (range: 0.3-32.4 months) and 16.7% and 10% of patients were alive at 1 and 2 years. respectively. Changes in the serum level of CA 19-9 provided an early marker of response which translated in differences in survival. Those with increasing or decreasing/stable levels of CA 19-9 after the first cycle of therapy had median survivals of 1.7 and 8.3 months, respectively (p = 0.0002). Although PACE chemotherapy produced durable responses in pancreatic cancer, the toxicity was substantial. A modification of this regimen with newer, less toxic drugs may provide better results and reduced toxicity. Also, the monitoring of the serum CA 19-9 level may provide a means to assess response and predict survival.

Two active forms of UDP-N-acetylglucosamine enolpyruvyl transferase in gram-positive bacteria

Gene sequences encoding the enzymes UDP-N-acetylglucosamine enolpyruvyl transferase (MurA) from many bacterial sources were analyzed. It was shown that whereas gram-negative bacteria have only one murA gene, gram-positive bacteria have two distinct genes encoding these enzymes which have possibly arisen from gene duplication. The two murA genes of the gram-positive organism Streptococcus pneumoniae were studied further. Each of the murA genes was individually inactivated by allelic replacement. In each case, the organism was viable despite losing one of its murA genes. However, when attempts were made to construct a double-deletion strain, no mutants were obtained. This indicates that both genes encode active enzymes that can substitute for each other, but that the presence of a MurA function is essential to the organism. The two genes were further cloned and overexpressed, and the enzymes they encode were purified. Both enzymes catalyzed the transfer of enolpyruvate from phosphoenolpyruvate to UDP-N-acetylglucosamine, confirming they are both active UDP-N-acetylglucosamine enolpyruvyl transferases. The catalytic parameters of the two enzymes were similar, and they were both inhibited by the antibiotic fosfomycin.

[The research development of single nucleotide polymorphism]

Single nucleotide polymorphism(SNP) is a novel set of polymorphism based on the single nucleotide variations at the genomic level, which distributes widely across the human genome and has high polymorphism information content (PIC). Now, tens of thousands SNPs have been discovered among the human genome and are introduced by many biological medicine networks. With the development of identification and analysis technique for SNP, especially the combination with DNA chips, they, as the third generation of genetic markers, are gradually fitable for fine-scale mapping of diseases, especially the complex diseases susceptibility genes and will eventually substitute for the most commonly used microsatellite markers presently.

RhoB alteration is necessary for apoptotic and antineoplastic responses to farnesyltransferase inhibitors

Farnesyltransferase inhibitors (FTIs) are in clinical trials, but how they selectively inhibit malignant cell growth remains uncertain. One important player in this process appears to be RhoB, an endosomal Rho protein that regulates receptor trafficking. FTI treatment elicits a gain of the geranylgeranylated RhoB isoform (RhoB-GG) that occurs due to modification of RhoB by geranylgeranyltransferase I in drug-treated cells. Notably, this event is sufficient to mediate antineoplastic effects in murine models and human carcinoma cells. To further assess this gain-of-function mechanism and determine whether RhoB-GG has a necessary role in drug action, we examined the FTI response of murine fibroblasts that cannot express RhoB-GG due to homozygous deletion of the rhoB gene. Nullizygous (-/-) cells were susceptible to cotransformation by adenovirus E1A plus activated H-Ras but defective in their FTI response, despite complete inhibition of H-Ras prenylation. Actin cytoskeletal and phenotypic events were disrupted in -/- cells, implicating RhoB-GG in these effects. Interestingly, -/- cells were resistant to FTI-induced growth inhibition under anchorage-dependent but not anchorage-independent conditions, indicating that, while RhoB-GG is sufficient, it is not necessary for growth inhibition under all conditions. In contrast, -/- cells were resistant to FTI-induced apoptosis in vitro and in vivo. Significantly, the apoptotic defect of -/- cells compromised the antitumor efficacy of FTI in xenograft assays. This study offers genetic proof of the hypothesis that RhoB-GG is a crucial mediator of the antineoplastic effects of FTIs.

Weekly 1-hour infusion of paclitaxel. Clinical feasibility and efficacy in patients with hormone-refractory prostate carcinoma

BACKGROUND

Preclinically, paclitaxel given according to an intense bolus schedule has significant antitumor activity against human prostate carcinoma cell lines in SCID mice. The authors evaluated the feasibility and efficacy of weekly 1-hour infusion of paclitaxel in patients with metastatic hormone-refractory prostate carcinoma (HRPC).

METHODS

A total of 18 patients with progressive metastatic HRPC were enrolled. Patients had to have no prior chemotherapy. Paclitaxel was infused weekly at a dose of 150 mg/m(2) over 1 hour for 6 weeks every 8 weeks.

RESULTS

Eighteen patients with a median age of 68.5 years and a median prostate specific antigen (PSA) level of 82 ng/mL (range, 2.17-3196 ng/mL) were enrolled. The median number of prior hormone treatments was 2, and 12 patients on antiandrogens completed antiandrogen withdrawal. Ten of eighteen patients had bone-only metastasis and eight had metastasis to bone with lymph node and/or visceral metastasis. Seventeen patients received a total of 31 cycles (157 courses) and 1 patient refused chemotherapy. All patients were included in response evaluation. Of the 8 [corrected] patients with measurable disease, 4 achieved a major response, with 1 complete response (in the lung) and 3 partial responses (1 in the liver and 2 in the lymph nodes). Seven of eighteen patients (39%) had a PSA decline of >/=50%. The major high grade toxicity was peripheral neuropathy, with 6 patients (35%) developing Grade 3 toxicity.

CONCLUSIONS

Weekly 1-hour paclitaxel has activity in patients with HRPC. The major toxicity is peripheral neuropathy. The minimal myelosuppressive effects make a modified schedule (lower doses on the same schedule or a shorter schedule of the same dose) attractive for future combination chemotherapy trials.

Overlapping roles for the histone acetyltransferase activities of SAGA and elongator in vivo

Elp3 and Gcn5 are histone acetyltransferases (HATs) that function in transcription as subunits of Elongator and SAGA/ADA, respectively. Here we show that mutations that impair the in vitro HAT activity of Elp3 confer typical elp phenotypes such as temperature sensitivity. Combining an elp3Delta mutation with histone H3 or H4 tail mutations confers lethality or sickness, supporting a role for Elongator in chromatin remodelling in vivo. gcn5Deltaelp3Delta double mutants display a number of severe phenotypes, and similar phenotypes result from combining the elp mutation with mutation in a gene encoding a SAGA-specific, but not an ADA-specific subunit, indicating that Elongator functionally overlaps with SAGA. Because concomitant active site alterations in Elp3 and Gcn5 are sufficient to confer severe phenotypes, the redundancy must be specifically related to the HAT activity of these complexes. In support of this conclusion, gcn5Deltaelp3Delta phenotypes are suppressed by concomitant mutation of the HDA1 and HOS2 histone deacetylases. Our results demonstrate functional redundancy among transcription-associated HAT and deacetylase activities, and indicate the importance of a fine-tuned acetylation-deacetylation balance during transcription in vivo.

Associative learning is enhanced by selective neuronal nitric oxide synthase inhibitors and retarded by a nitric oxide donor in the rabbit

RATIONALE

Previous studies had reported that the nitric oxide (NO) donor, sodium nitroprusside (SNP), retarded and the non-specific NO synthase (NOS) inhibitor, Nomega-nitro-L-arginine methyl ester (L-NAME), enhanced acquisition of classically conditioned responses (CRs). These effects of IV SNP and IP L-NAME on CR acquisition occurred in the absence of any effect on non-associative processes or performance variables and at a time when there were no alterations in blood pressure or heart rate.

OBJECTIVES

In this study, we examined whether the changes in associative learning produced by L-NAME and SNP were due to their central effects on NO content of brain. To this end, we examined the effects of the selective neuronal NOS inhibitors 7-nitroindazole (7-NI) and AR-R 17477 and the effects of central (ICV) administration of the NO donor SNP on learning.

METHODS

Effects of drugs on CR acquisition were determined during classical conditioning of the rabbit's nictitating membrane (NM) response. Explicitly unpaired presentations of conditioned stimuli (CSs) and unconditioned stimuli (USs) were employed to measure non-associative levels of responding and unconditioned response (UR) topography.

RESULTS

The SC injection of 7-NI and AR-R 17477 significantly enhanced associative learning while ICV administration of SNP significantly retarded learning.

CONCLUSION

Production of NO within the brain by neuronal NOS normally acts to retard associative learning presumably by decreasing excitability within neuronal circuits involved in the acquisition of the classically conditioned NM reflex.

Cardiac sequelae of doxorubicin and paclitaxel as induction chemotherapy prior to high-dose chemotherapy and peripheral blood progenitor cell transplantation in women with high-risk primary or metastatic breast cancer

Doxorubicin plus paclitaxel has been shown to be an active regimen for metastatic breast cancer and is now frequently used as adjuvant therapy for high-risk primary breast cancer. Initial studies reported a higher than expected rate of cardiac toxicity with this regimen. We studied 105 patients with either high-risk primary breast cancer or metastatic breast cancer who were treated with doxorubicin (60 mg/m2) and 3-h infusions of paclitaxel (175 mg/m2) cycled every 3 weeks. Patients received three cycles of chemotherapy for high-risk primary or four cycles for metastatic disease. Patients then proceeded to high-dose chemotherapy (HDC) (STAMP I cyclophosphamide, cisplatin and carmustine) and peripheral blood progenitor cell transplantation (PBPCT). Patients underwent radionuclide multi-gated angiograms (MUGA) before and following induction chemotherapy and following HDC. During induction chemotherapy 40 (38%) of the patients had a reduction in left ventricular ejection fraction (LVEF). Fourteen had a decrease of 20% or greater and two were mildly symptomatic from CHF. There was additional reduction in the LVEF after HDC with a median value for LVEF of 59% (range, 20-78%). During HDC 10 patients developed clinical signs of congestive heart failure (CHF). Five patients responded to diuretic therapy and did not require any additional treatment. Four patients responded to vasodilation and/or digoxin with improvement in cardiac function. A clinically significant decrease in cardiac function was found in a small number of patients after induction chemotherapy and HDC with PBPCT. The majority of the patients tolerated this regimen without problems. Although there was a decline in LVEF as measured by radionuclide MUGA this did not prevent the majority of patients from proceeding with HDC. Bone Marrow Transplantation (2000).

Expression of fibronectin receptor, integrin alpha 5 beta 1 of hepatic stellate cells in rat liver fibrosis

OBJECTIVE

To investigate the role of fibronectin (FN) receptor alpha 5 beta 1 in liver fibrosis.

METHODS

Northern blot analysis and immunohistochemical techniques were used to observe changes in the expression of FN and FN receptor alpha 5 beta 1 on hepatic stellate cells (HSCs) in vivo and in vitro of rat liver fibrosis induced by CCl4.

RESULTS

(1) alpha 5 beta 1 was mainly detected in the endothelia and some of the desmin(DM) positive cells of the sinusoids in normal rat liver. The expression of alpha 5 beta 1 of DM positive cells detected by immunohistochemistry reached its peak at the 10th week of the experiment. The changes in FN expression were similar to that of alpha 5 beta 1. (2) The expression of FN, alpha 5 and beta 1 mRNAs in the experimental group was remarkably increased especially at the 6th week, compared to that of normal liver specimens. The expression of the three mRNAs of HSCs in vitro isolated from the experimental group (6 weeks) was higher than those from normal liver. (3) The expression of FN, alpha 5 and beta 1 mRNAs increased in normal rat HSCs after treatment with transforming growth factor-beta 1 (TGF-beta 1) for 2 hours. After 4 hours of treatment, the expression of the three mRNAs fell to levels similar to the control group. Immunocytochemistry revealed that the expression of alpha 5 beta 1 of HSCs reached its peak after 4 hours of treatment with TGF-beta 1 and dropped to normal 2 hours later.

CONCLUSION

These data suggest that HSCs normally express FN receptor alpha 5 beta 1. The activation of HSCs during liver fibrogenesis leads to an increase of FN, alpha 5 and beta 1 mRNA expression. The expression of FN and alpha 5 beta 1 of HSCs in vitro is up-regulated by TFG-alpha 5 beta 1. The detection of gene transcription of FN and its receptor by Northern blot analysis suggests the activation and proliferation of HSCs and thereby provides a sensitive signal of liver fibrosis.

[Determination of O6-methylguanine by high performance capillary zone electrophoresis]

In this paper, a method to determine O6-methylguanine in urine by high performance capillary zone electrophoresis has been established. O6-methylguanine was directly introduced into the capillary employing sodium borate at pH 9.0 as buffer. The capillary used was 75 microns i.d. x 57 cm. The calibration curve showed good linearity, r = 0.9987, CVs were 1.51% for intra-day and 1.93% for inter-day. The average recovery was 98.2%. In conclusion, this method is a simple, rapid, precise and reliable technique for O6-methylguanine measurement in urine.

[Antibody to human herpesvirus type-8 in the general populations of Xinjiang Autonomous Region(A.R.)]

OBJECTIVE

Kaposi 's sarcoma (KS) does not rarely occur in Xinjiang A. R. Much of the evidence show that human herpes virus-8 (HHV-8) is associated with KS, and the different incidence of classic KS among different countries reflects the different prevalence in general populations. The aim of this study was to know whether the prevalence of HHV-8 is higher in general populations of Xinjiang than the other places of the country.

METHODS

We used BCBL-1 cell line as antigen and collected 1071 serum sample of different nationalities (Uighur, Khalkhas, Kazak and Han nationality) from south and north regions of Xinjiang A. R. for detection of HHV-8 IgG antibody by IFA.

RESULTS

The results showed that HHV-8 IgG antibody positive rate in Khalkhas was 48% (96/200), Uighur 30.4%(62/204), Kazak 12.5% (25/200) and Han 16.9% (79/467). While sera were diluted in 1:20, the positive rate in Khalkhas still was as high as 30.5% (61/200). In addition, the positive rate of HHV-8 IgG antibody in minorities in the same native area all were higher than Han except Kazak nationality.

CONCLUSIONS

These data illustrated that the prevalence of HHV-8 IgG antibody in general populations of different nationality was different, Khalkhas and Uighur were higher than Kazak and Han. Most of the KS cases were reported from Uighur nationality, but no case was reported from Khalkhas thought a highest HHV-8 IgG antibody detection rate (48%) there was demonstrated. The reason for it would be further studied.

Assessment of carotid artery invasion in patients with head and neck cancer

PURPOSE

Define radiological and histological features in which patients with head and neck cancer would benefit from a carotid artery resection. Resection of the carotid artery has been advocated for local control of advanced squamous cell carcinoma of the head and neck. To provide appropriate preoperative counseling and optimize the utilization of resources, the criteria for patient selection has to be defined.

METHODS

Thirty-four patients underwent carotid artery resection based on the clinical impression of tumor fixation. Eighteen and 28 patients were evaluated using computed tomography (CT) and histological analysis, respectively. The distance between the tumor cells and external elastic lamina was measured. CT scans were examined to determine the circumference of tumor attachment around the carotid artery.

RESULTS

Clinical assessment predicted tumor within 1.8 mm of the carotid artery in 68% of cases. The overall survival for patients with tumor greater than 1.8 mm (N = 9) was better than that of patients with less (N = 19) than 1.8 mm (33.3% vs. 5.3%; median 24 versus 9 mo, P = .0899). Three of six patients (50%) with less than 180 degrees circumference tumor attachment had tumor within 1.8 mm from the external elastic lamina. Eight of twelve patients (67%) with tumors encompassing more than 180 degrees of the artery wall had tumor within 1.8 mm from the external elastic lamina. The overall survival rates for patients with tumor attachment greater and less than 180 degrees were 8.3% and 33%, respectively.

DISCUSSION

Tumor invasion into the carotid artery was the strongest predictor of outcome. Clinical assessment was as predictive as CT for tumor invasion. If tumor involvement of the carotid artery is less than 180 degrees, peeling the tumor is an alternative to carotid artery resection.

beta-Lactamase epidemiology and the utility of established and novel beta-lactamase inhibitors

beta-Lactamase inhibitor:beta-lactam combinations remain one of the most successful strategies for the treatment of bacterial infections. Over the last 20 years the number and diversity of serine and metallo active site beta-lactamases has increased dramatically. This review highlights some of the new additions to the beta-lactamase arena and discusses how the commercially available beta-lactamase inhibitors are keeping pace with the changing epidemiology of beta-lactamases. In addition, we survey the progress with the design of novel inhibitors of serine and metallo-beta-lactamases. Focus is given to the recent advances in the design of metallo-beta-lactamase inhibitors as these enzymes pose a serious emerging threat to the use of all beta-lactam based therapies.

[Determination of kalium in husked seed food by suspension sampling-flame atomic emission spectrometry]

Suspension sampling technique was applied to flame atomic emission spectrometry and Kalium in husked rice, millet and husked Kaoliang successfully determined. A new method for rapid determination of kalium was developed. The samples were grinded and then made into agar suspension. NaCl solution was added to an appropriate amount of suspension for eliminating ionijation interference, and test solution prepared. The test solution was injected into air-acetylene flame. The working curve method was used for the determination. Results were consistent with those obtained by ashing method. RSD < 3.0%. Relative error of the two methods was less than +/- 1.8%. The t-test showed that no difference was found. This method is convenient, rapid and accurate.

Suppression of the rbf null mutants by a de2f1 allele that lacks transactivation domain

In mammals, a large number of proteins including E2F transcription factors have been shown to interact with the tumor suppressor gene product pRB, but it is not clear to what extend the function of pRB is mediated by E2F. In addition, E2F was shown to mediate both transcription activation and repression; it remains to be tested which function of E2F is critical for normal development. Drosophila homologs of the RB and E2F family of proteins RBF and dE2F1 have been identified. The genetic interactions between rbf and de2f1 were analyzed during Drosophila development, and the results presented here showed that RBF is required at multiple stages of development. Unexpectedly, rbf null mutants can develop until late pupae stage when the activity of dE2F1 is reduced, and can develop into viable adults with normal adult appendages in the presence of a de2f1 mutation that retains the DNA binding domain but lacks the transactivation domain. These results indicate that most, if not all, of the function of RBF during development is mediated through E2F. In turn, the genetic interactions shown here also suggest that dE2F1 functions primarily as a transcription activator rather than a co-repressor of RBF during Drosophila development. Analysis of the expression of an E2F target gene PCNA in eye discs showed that the expression of PCNA is activated by dE2F1 in the second mitotic wave and repressed in the morphogenetic furrow and posterior to the second mitotic wave by RBF. Interestingly, reducing the level of RBF restored the normal pattern of cell proliferation in de2f1 mutant eye discs but not the expression of E2F target genes, suggesting that the coordinated transcription of E2F target genes does not significantly affect the pattern of cell proliferation.

Simulation modeling of nuclear steam generator water level process--a case study

Simulation modeling of the nuclear steam generator (SG) water level process in Qinshan Nuclear Power Plant (QNPP) is described in this paper. A practical methodology was adopted so that the model is both simple and accurate for control engineering implementation. The structure of the model is in the form of a transfer function, which was determined based on first-principles analysis and expert experience. The parameters of the model were obtained by taking advantage of the recorded historical response curves under the existing closed-loop control system. The results of process dimensional data verification and experimental tests demonstrate that the simulation model depicts the main dynamic characteristics of the SG water level process and is in accordance with the field recorded response curves. The model has been successfully applied to the design and test of an advanced digital feedwater control system in QNPP.

Characterization of Streptococcus pneumoniae 5-enolpyruvylshikimate 3-phosphate synthase and its activation by univalent cations

The aroA gene (Escherichia coli nomenclature) encoding 5-enolpyruvylshikimate-3-phosphate (EPSP) synthase from the gram-positive pathogen Streptococcus pneumoniae has been identified, cloned and overexpressed in E. coli, and the enzyme purified to homogeneity. It was shown to catalyze a reversible conversion of shikimate 3-phosphate (S3P) and phosphoenolpyruvate (PEP) to EPSP and inorganic phosphate. Activation by univalent cations was observed in the forward reaction, with NH+4, Rb+ and K+ exerting the greatest effects. Km(PEP) was lowered by increasing [NH+4] and [K+], whereas Km(S3P) rose with increasing [K+], but fell with increasing [NH+4]. Increasing [NH+4] and [K+] resulted in an overall increase in kcat. Glyphosate (GLP) was found to be a competitive inhibitor with PEP, but the potency of inhibition was profoundly affected by [NH+4] and [K+]. For example, increasing [NH+4] and [K+] reduced Ki(GLP versus PEP) up to 600-fold. In the reverse reaction, the enzyme catalysis was less sensitive to univalent cations. Our analysis included univalent cation concentrations comparable with those found in bacterial cells. Therefore, the observed effects of these metal ions are more likely to reflect the physiological behavior of EPSP synthase and also add to our understanding of how to inhibit this enzyme in the host organism. As there is a much evidence to suggest that EPSP synthase is essential for bacterial survival, its discovery in the serious gram-positive pathogen S. pneumoniae and its inhibition by GLP indicate its potential as a broad-spectrum antibacterial target.