[Current status of HIV infection in Yunnan Province of China]

In cooperation with the Chinese Academy of Preventive Medicine and Yunnan Province Provincial Office for AIDS Control and Prevention, we studied the current status of HIV infection intravenous drug users (IVDUs) and other high risk groups in Yunnan province of China. As of the end of 1995, 1,807 HIV cases were officially reported (Positive rate was 0.6%), of which 1,278 (77.9%) were IVDUs, and 24 were their spouses. The majority of cases were found among the Dai minority male farmers near Ruili which borders on Myammar, but HIV also appears to be spreading among the Han people. HIV antibody positive rates among commercial sex workers, pregnant women and blood donors were 0.2%, 0.07% and 0.04%, respectively. A system for surveillance of HIV has been developed, but preventive strategies to cope with HIV epidemic are not sufficient. As HIV/AIDS is now a global issue, (1) the integration and coordination of such preventive strategies in cooperation with community health workers, (2) general health education for condom use promotion and (3) care of psychological vulnerable person such as IVDUs, should be developed.

[An early phase II study of gemcitabine hydrochloride (LY 188011). Gemcitabine Cooperative Study Group for Early Phase II]

An early phase II cooperative study of Gemcitabine Hydrochloride (abbreviated to "gemcitabine" herewith) was conducted in patients with a variety of solid tumors (i.e., lung cancer, gastric cancer, pancreatic cancer, colon/rectum cancer, cervical cancer, ovarian cancer and breast cancer) at 56 institutions. The aim of the first step (Step I) was to investigate the feasibility of gemcitabine in a variety of different solid tumors, including lung cancer regarding efficacy and safety. The aim of the second step (Step II) was as a result of step I (Responses were observed) to continue to investigate the efficacy and safety of gemcitabine in chemonaive patients with non-small cell lung cancer. As a Step I study, gemcitabine was administered once weekly at a dose of 800 mg/m2 for a consecutive 3-week period followed by a week of rest, in multiple courses. Among the 29 eligible patients with lung cancer, partial response (PR) was achieved in 3 patients (25.0%, 95% confidence interval: 5.5-57.2%) out of 12 chemonaive patients. Adverse reactions (grade 3 or higher) seen in 29 patients with lung cancer were neutropenia (27.6%), leukopenia (13.8%), decreased hemoglobin (13.8%), thrombocytopenia (10.3%), malaise (6.9%), anorexia (3.4%), nausea/vomiting (3.4%), diarrhea (3.4%), dyspnea (3.4%) and interstitial pneumonia (3.4%). In other types of solid tumors, PR was achieved in 2 (8.7%) out of 23 eligible patients with cervical cancer and in 1 (5.3%) of 19 eligible patients with ovarian cancer, while the use of analgesics became unnecessary in 1 patient with pancreatic cancer. Incidence as well as severity of main adverse reactions in these patients were comparable to those seen in patients with lung cancer. A Step II study, in which gemcitabine was administered once weekly at a dose of 1,000 mg/m2 to chemonaive patients with non-small cell lung cancer, was conducted, referring to the results of Step I and clinical studies conducted overseas. The results of the Step II study demonstrated PR in 5 (14.3%, 95% confidence interval: 4.8 - 30.3%) out of 35 eligible patients with non-small cell lung cancer and that the main adverse reactions were comparable to those seen in the Step I study, posing no tolerability problems in particular.

Study of anionic sites on the mesangium in aminonucleoside nephrosis

In recent years, various reports have appeared concerning anionic sites in glomerular lesions. However, no detailed results for anionic sites in the mesangium have been reported. The authors therefore prepared nephrotic rats by the administration of puromycin aminonucleoside (PA) and investigated the anionic sites in various mesangial regions, using polyethyleneimine (PEI) as a cationic probe. In the mesangium of the control group as well as the experimental groups, PEI particles were most numerous in the subendothelial regions, followed by the central region and paramesangial region, in that order. In the group treated with PA, the numbers of PEI particles in each mesangial region decreased as compared with those in the control group. Among the three mesangial regions considered, this decrease was most pronounced in the paramesangial region. In the group which received elastase, no significant decrease in numbers of PEI particles was observed in subgroups I and II, indicating maintenance of the anionic sites. The results obtained suggested that regional investigations of the mesangial matrix may be of considerable significance for elucidating the etiologic factors in glomerular sclerosis, and that negative charge impairment in the mesangial matrix plays an important role in the development of glomerular sclerotic lesions.

[Treatment of advanced ovarian cancer]

Significant prolongation of survival time has been brought by cisplatin containing regimen, but no significant improvement of 5 year survival rate has been achieved. Concerning to four clinical problems we face to now, my opinion was described as follows. 1) Importance of chemotherapy in the treatment of advanced ovarian cancer: The most important factor for the cure of advanced ovarian cancer is the efficacy of the regimen used. 2) Regimen and number of cycles needed: Cisplatin and carboplatin are dose-dependent drugs and we should make effort to make dose up as much as possible. May be 6 cycles will be suitable number of administration. 3) Postoperative chemotherapy or preoperative chemotherapy (Neo-adjuvant)?: Serous adenocarcinoma is observed with high frequency around 70% and the efficacy rate of cisplatin containing regimen is exceeded more than 80%. Neo-adjuvant chemotherapy should be tried in advanced ovarian cancer. 4) Second line chemotherapy: At present, no effective drug is available for the treatment of true cisplatin refractory cancer. Therefore we should perform aggressive surgery and severe chemotherapy at the first time of treatment. By combination of surgery and chemotherapy, at least clinical CR (Complete resection or complete response) is indispensable for achieving significant improvement of 5 year survival rate, In this meaning, chemotherapeutic CR is necessary in postoperative chemotherapy and surgical CR is required in Neo-adjuvant chemotherapy.

[Phase II study of carboplatin in ovarian cancer]

A phase II study of carboplatin was conducted in ovarian cancer by a cooperative study group consisting of 22 institutions nationwide. The overall response rate of 50 evaluable cases was 38.0%. The response rate in cases with no prior chemotherapy was 54.2% and that with prior chemotherapy was 23.1%. In addition, the response rate was 26.3% in cases that received prior CDDP-based chemotherapy. Histologically, the response rate was high in serous cystadenocarcinoma and endometrioid adenocarcinoma. Hematologic toxicities, particularly leukopenia and thrombocytopenia, were frequently observed, but well tolerated, while renal and neurologic toxicities were rare. These results suggested that carboplatin is useful in the treatment of ovarian cancer.

[Clinical study of intramuscular imipenem/cilastatin sodium in the field of obstetrics and gynecology]

The efficacy and the safety of intramuscular imipenem/cilastatin sodium (IPM/CS) were evaluated in 22 patients with obstetric and gynecologic infections. 0.5 g/0.5 g of IPM/CS was suspended in a lidocaine solution and administered in the gluteal muscle twice a day for 3-7 days. Nineteen patients with intrauterine infections were evaluable for the clinical efficacy and 22 for the safety. 1. Clinical efficacies were excellent in 6 patients, good in 11 and poor in 2, and the efficacy rate was 89.5%. Thirteen out of 14 patients who had not responded to treatments with other previously administered antibiotics showed excellent or good responses to IPM/CS. 2. Causative bacteria were eradicated in 5 patients, decreased in 2, unchanged in 3 and replaced in 3, with an eradication rate of 61.5%. 3. Among 22 patients treated with IPM/CS, an eruption and general itching were observed in 1 patient, but no abnormal laboratory test values were observed.

[A case of the primary pancreatic lymphoma]

Primary pancreatic lymphoma is extremely rare. A case of the primary pancreatic lymphoma was described. A 74-year-old man was admitted to our hospital on May 26, 1990, because of epigastralgia and 5-kg weight loss. On admission, physical examination revealed mild epigastric tenderness without hepatosplenomegaly and superficial lymphadenopathy. The serum amylase level and trypsin level were normal but serum CA19-9 was slightly elevated. The diagnosis of the pancreatic cancer (body and tail) was strongly suspected on subsequent examination by US, CT, ERP and angiography. Partial pancreatectomy and splenectomy were performed. Pathological examination of the tumor in the pancreas showed diffuse non-Hodgkin's lymphoma and B-cell origin. Peripancreatic fat was involved but peripancreatic lymph nodes and spleen were intact, which strongly suggested that the isolated lymphoma was pancreatic origin.

[Fundamental and clinical studies of imipenem and imipenem/cilastatin sodium in the field of obstetrics and gynecology]

Fundamental and clinical studies of imipenem (MK-0787), a new type of carbapenem antibiotic, and MK-0787 combined with cilastatin sodium (MK-0791), a renal dipeptidase inhibitor, were carried out. The results obtained were as follows: MK-0787 500 mg alone or MK-0787 500 mg with MK-0791 500 mg was administered by intravenous drip infusion over 30 minutes. Plasma levels of the drug were similar either following the administration of 500 mg of MK-0787 alone or 500 mg of MK-0787 with 500 mg of MK-0791. When MK-0787 was administered with MK-0791, MK-0787 and MK-0791 levels at 2 hours after the end of infusion in uterine arterial plasma were 6.8 micrograms/ml and 3.2 micrograms/ml, respectively, and in venous plasma were 8.4 micrograms/ml and 4.7 micrograms/ml, respectively. MK-0787 tissue levels ranged from 0.8 microgram/g to 3.8 micrograms/g at 205 minutes after the end of infusion. Based on these results, the plasma and tissue levels of MK-0787 and MK-0791 with b.i.d. dosage exceeded the MICs of the drug against clinical isolates in the field of obstetrics and gynecology such as E. faecalis, E. coli Klebsiella sp., Peptococcus sp., Peptostreptococcus sp. and B. fragilis immediately after the administration. However, it seemed that the b.i.d. dosage was insufficient to maintain the in vivo concentration of these agents high enough to inhibit the growth of the above bacteria. Eighteen patients with obstetric and gynecologic infection (12 with intrauterine infections, 2 with pelvic dead space inflammation, 2 with pelvic peritonitis, 1 with a vaginal cuff abscess and 1 with a vulvar abscess) and 1 patient with other infection (abdominal wall abscess) were evaluated, but 1 patient with pelvic peritonitis was later excluded from the efficacy evaluation because of a serious illness. MK-0787/MK-0791 was administered twice daily in a 30-minute intravenous drip infusion. Clinical results were excellent in 1 patient, good in 16 and poor in 1, for an efficacy ratio of 94.4%. No side effects were observed. Only abnormal laboratory findings observed were elevation of S-GOT and S-GPT in 1 patient which normalized 2 weeks after the treatment was discontinued. These results suggest that MK-0787/MK-0791 will be useful for the treatment of obstetric and gynecologic infections.

[Laboratory and clinical studies on latamoxef in the field of obstetrics and gynecology]

Latamoxef (LMOX) is a new antibiotic synthesized by Shionogi Research Laboratory. Chemically LMOX is especially unique with a sulfur atom replacing the oxygen atom in the 1 position of the conventional cephalosporin nucleus, and in addition, this antibiotic has a cephamycin-like structure. The antibacterial activity of LMOX shows high potency against Gram-negative bacteria, but tends to be weak against Gram-positive bacteria. The tissue levels of LMOX in humans after intravenous injection of 1 g were examined. The levels in uterine and adnexa uteri tissue at 1 hour after administration were 25.4 and 27.4 micrograms/g respectively. LMOX was administered to 147 cases in infections of obstetric and gynecological field. The clinical effect according to disease was 94.6% for intrauterine infections, 95.0% for adnexitis, 87.0% intrapelvic infections, and 100% for external genital organ infections, making a total of 92.5%. The rate of occurrence of side effects or abnormal laboratory findings was similar to or slightly less than that seen with other beta-lactam antibiotics.

[Phase III study of carboplatin in ovarian cancer]

A phase III study of carboplatin vs cisplatin in CAP regimen for ovarian cancer was conducted by a cooperative study group consisting of 22 institutions nationwide. The response rate for 23 cases allocated to carboplatin regimen group was 34.8% and 42.1% for 19 cases allocated to cisplatin regimen group. No significant difference was observed between these two regimens in response rates, and no significant differences were noted between the two regimens in each of the clinical toxicities and abnormalities in laboratory findings. Since the carboplatin regimen group did not require hydration, or the use diuretics or antiemetics, these results suggested that carboplatin is more useful in the treatment of ovarian cancer than cisplatin.

Inhibition of metastatic carcinoma cell growth in livers by poly(I):poly(C)/cationic liposome complex (LIC)

The complex of poly(I):poly(C) and a new cationic liposome (LIC) has a potent antitumor activity against many tumor cell lines in vitro, whereas poly(I):poly(C) itself has no such activity. In the present study we tested the sensitivity of 21 human colon and pancreatic cancer cell lines to LIC or Adriamycin in vitro. The growth of most of the cell lines was strongly inhibited by both LIC and Adriamycin in vitro, although a few insensitive cell lines were different. We also studied the in vivo antitumor activity of LIC or Adriamycin in three experimental liver metastasis models in nude mice using a human pancreatic cancer cell line (AsPC-1) and two human colon cancer cell lines (Ls174T and HCC-M1544). The administration of LIC or Adriamycin was started 3 days after the injection of tumor cells. Animals received 0.1 mg/kg LIC IV twice weekly or 5 mg/kg Adriamycin IV every 5 days during the experiments. LIC showed potent antitumor activity in all three liver cancer models. Although Adriamycin had potent antitumor activity in the HCC-M1544 model, it had only a moderate effect in the AsPC-1 model and at most a weak effect in the Ls174T model. At the effective doses LIC did not cause detectable pathological changes in the liver and did not elicit toxicity to mice in these models, whereas Adriamycin did exhibit toxic effects. These results suggest that LIC is a promising candidate drug to treat hepatic metastasis.