N10-propargyl-5,8-dideazafolic acid (CB3717): inhibitory effects on human leukemia cell lines resistant to methotrexate or trimetrexate

The inhibitory effects of N10-propargyl-5,8-dideazafolic acid (CB3717), a quinazoline antifolate and a potent thymidylate synthase inhibitor, were evaluated in human leukemia cell lines resistant to methotrexate (MTX) and trimetrexate (TMQ). MTX-resistant MOLT-3 cell lines, MOLT-3/MTX200 and MOLT-3/MTX10,000, were cross-resistant to CB3717; however, the degree of resistance was only tenfold for both cell lines, and increased dihydrofolate reductase activity in MOLT-3/MTX10,000 had little influence on the degree of CB3717 resistance. The MOLT-3 cell line made resistant to TMQ, MOLT-3/TMQ200, was as sensitive to CB3717 as the parent line. The cell growth inhibitory effect of CB3717 on MOLT-3 was reversed by the addition of thymidine. Leucovorin also partially reversed CB3717-induced growth inhibition. Cellular uptake of MTX and 5-methyl-tetrahydrofolate was hindered by the presence of a high concentration of CB3717, whereas TMQ uptake was not influenced by CB3717. CB3717 appears to enter the cells not only through reduced folate transport system, but by other route(s). CB3717 does not share the transport pathway with TMQ. Our observations that MTX-resistant cells with increased dihydrofolate reductase are not more resistant than cells without increased enzyme activity, and that TMQ-resistant cells are not cross-resistant to CB3717, may have clinical relevance.

The results of the "essential laboratory tests" applied to new outpatients--re-evaluation of diagnostic efficiencies of the test items

We have analyzed diagnostic efficiencies of the individual "Essential laboratory test" items when these tests were applied to 520 new outpatients in the division of comprehensive medicine in a teaching hospital. The integration of these test results with history-taking and physical examination resulted in 544 primary clinical diagnoses which corresponded to the patient's illness complained and in 361 additional diagnoses unrelated to their chief complaints but found by chance by the addition of the test results. Clinical usefulness of these test items were variable depending on the disease category, demonstrating a superior diagnostic efficiency in infectious or inflammatory diseases, liver and biliary tract diseases, hematological disorders or metabolic diseases such as hyperlipidemia and diabetes mellitus, but a lesser degree of usefulness in gastro-intestinal or neurogenic diseases. Urine urobilinogen could not establish its clinical usefulness because of extremely low diagnostic sensitivity even in liver diseases. The leukocyte differential count provided confirmatory information for infectious or inflammatory diseases and was helpful for the estimation of the etiologic nature of infectious diseases. This study failed to terminate a controversy for the adoption of sialic acid instead of erythrocyte sedimentation rate (ESR) in the "Essential laboratory test" items, since the former test showed lower sensitivity, even though higher specificity, in infectious or inflammatory status than ESR. Low albumin globulin ratio (A/G) revealed equivalent diagnostic sensitivity and specificity to the elevated levels in alpha 1 and/or alpha 2 globulin fractions in infectious or inflammatory status, being helpful for the evaluation of patient's general condition at a glance. Incidental analysis for diagnostic values of cholinesterase and random blood glucose for the detection of fatty liver and diabetes mellitus, respectively, suggested that these two tests may be included in the "Essential laboratory tests". Simultaneous measurement of serum creatinine and blood urea nitrogen levels was recommended for the ambulatory screening of renal insufficiency, rather than the measurement either alone. The results in this study provide scientific bases on the usefulness of the individual test items and should be taken into account in the next version of the "Essential laboratory tests".

Development of 2D soft X-ray measurement system in the large helical device

A fast two-dimensional soft X-ray camera using silicon photo diode array is being developed in order to investigate high frequency MHD instability with high mode number. The advantage of the adopted diode is a large sensor area of 10 mm × 10 mm and small diode capacitance which enable us to measure signals with the short response time. The characteristic of the prototype is summarized as follows: Channel number is 6 × 8 = 48, detection range 1∼10 keV, the spatial resolution 128 mm at the plasma location, and frequency range DC∼100 kHz. Synthetic image of the prototype in the Large Helical Device is estimated by using perturbation model of MHD mode.

Impact of the COVID-19 pandemic on short-term outcomes after pancreaticoduodenectomy for pancreatic cancer: A retrospective study from the Japanese National Clinical Database, 2018-2021

Aim

The coronavirus disease 2019 (COVID-19) pandemic greatly impacted medical resources such as cancer screening, diagnosis, and treatment given to people for various diseases. We surveyed the impacts of the pandemic on the incidence of complications and mortality following pancreaticoduodenectomy for pancreatic cancer in Japan.

Methods

Data on patients who underwent pancreaticoduodenectomy for pancreatic cancer were extracted from the Japanese National Clinical Database (NCD) between 2018 and 2021. The number of the pancreaticoduodenectomy for pancreatic cancer were obtained and then the morbidity and mortality rates were evaluated using a standardized morbidity/mortality ratio (SMR), which is the ratio of the observed number of incidences to the expected number of incidences calculated by the risk calculator previously developed by the NCD.

Results

This study included 22 255 cases. The number of pancreaticoduodenectomies exhibited an increasing trend even during the COVID-19 pandemic. The mean observed incidence rates of Grade C pancreatic fistula and Clavien-Dindo grade ≥4 complications, and the 30-day mortality and surgical mortality rates were 0.8%, 1.8%, 0.8% and 0.9%, respectively. The standardized morbidity ratios did not increase during the COVID-19 pandemic. The standardized mortality ratios remained within the range of variations observed before the COVID-19 pandemic.

Conclusion

The increasing trend in the number of pancreaticoduodenectomies and favorable short-term outcomes even in the COVID-19 pandemic suggest the medical care for pancreatic cancer in Japan functioned well during the pandemic.

Impact of SARS-CoV-2 infection on short-term postoperative outcomes after gastroenterological cancer surgery using data from a nationwide database in Japan

Background

Due to the coronavirus disease 2019 (COVID-19) pandemic, cancer screening, diagnosis, and treatment have changed. This study aimed to investigate the impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection prior to gastroenterological cancer surgeries on postoperative complications using data from a nationwide database in Japan.

Methods

Data on patients who underwent surgery for cancer including esophageal, gastric, colon, rectal, liver, and pancreatic cancer between July 1, 2019, and September 300, 2022, from real-world sources in Japan were analyzed. The association between preoperative SARS-CoV-2 infection and short-term postoperative outcomes was evaluated. A similar analysis stratified according to the interval from SARS-CoV-2 infection to surgery (<4 vs. >4 weeks) was conducted.

Results

In total, 60 604 patients were analyzed, and 227 (0.4%) patients were diagnosed with SARS-CoV-2 infection preoperatively. The median interval from SARS-CoV-2 infection to surgery was 25 days. Patients diagnosed with SARS-CoV-2 infection preoperatively had a significantly higher incidence of pneumonia (odds ratio: 2.05; 95% confidence interval: 1.05-3.74; p = 0.036) than those not diagnosed with SARS-CoV-2 infection based on the exact logistic regression analysis adjusted for the characteristics of the patients. A similar finding was observed in patients who had SARS-CoV-2 infection <4 weeks before surgery.

Conclusions

Patients with a history of SARS-CoV-2 infection had a significantly higher incidence of pneumonia. This finding can be particularly valuable for countries that have implemented strict regulations in response to the COVID-19 pandemic and have lower SARS-CoV-2 infection-related mortality rates.