gamma-Glutamylcysteine ethyl ester for myocardial protection in dogs during ischemia and reperfusion

OBJECTIVES

The aim of this study was to examine the infarct-limiting effects of gamma-glutamylcysteine ethyl ester, a newly discovered synthetic precursor of glutathione biosynthesis, in a canine model of myocardial infarction.

BACKGROUND

Reduced glutathione plays an important role in protecting cells against damage induced by reactive oxygen species during myocardial ischemia and reperfusion. Gamma-glutamylcysteine ethyl ester is capable of penetrating into cells in its intact form and increasing intracellular glutathione levels.

METHODS

Dogs were subjected to a 90-min coronary occlusion followed by 5 h of reperfusion. An intravenous bolus injection of gamma-glutamylcysteine ethyl ester (3 or 10 mg/kg body weight) was administered immediately before reperfusion. Regional myocardial blood flow was measured with the use of colored microspheres.

RESULTS

Gamma-glutamylcysteine ethyl ester effectively reduced infarct size in a dose-dependent manner (mean +/- SEM 26.4 +/- 3.5% in the low dose group [3 mg/kg, n = 10] and 19.0 +/- 3.4% in the high dose group [10 mg/kg, n = 10]; each p < 0.05 vs. the value in the control group [40.6 +/- 4.8%, n = 10]). There were no differences between the control and treated groups in hemodynamic variables or regional myocardial blood flow either during the ischemic period or after reperfusion. The reduced glutathione content of ischemic myocardium in the control group (0.62 +/- 0.11 mumol/g, p < 0.01) was significantly lower than that in nonischemic myocardium (1.46 +/- 0.07 mumol/g), and it was preserved by treatment in a dose-dependent manner (3 mg/kg, 0.83 +/- 0.06 mumol/g; 10 mg/kg, 0.92 +/- 0.14 mumol/g; each p < 0.05 vs. control level). There were no differences in oxidized glutathione content between nonischemic and ischemic myocardium or among the three groups.

CONCLUSIONS

Gamma-glutamylcysteine ethyl ester, a precursor of glutathione, significantly attenuates myocardial ischemia and reperfusion injury when administered immediately before reperfusion.

[Treatment results of radical nephrectomy for relatively confined small renal cell carcinoma--translumbar versus transabdominal approach]

We performed radical nephrectomy for 166 patients with renal cell carcinoma over 25 years period between 1967 and 1991. Among them, 49 patients had stage T1-3 NOMOVO tumors less than 6 cm in maximum diameter. Twenty-seven of them received radical nephrectomy by a modified translumbar approach whereas the conventional transabdominal approach was applied to the remaining 22 patients. We retrospectively studied treatment results of the 49 patients to evaluate the current translumbar approach. There was no significant difference in the age and sex distribution of the patients, and the size, stage, grade and histological subtype of the tumor between translumbar and transabdominal groups, although the incidence of venous invasion (pVla) was significantly greater in translumbar group. Statistical analysis revealed shortened operating time, decreased blood loss and quickened postoperative recovery (resuming oral intake or walking) in translumbar group as compared to those in transabdominal group. No major complication was observed in both groups. There was no significant difference in actuarial survival rate or disease-free survival period between the two groups. Actuarial three-year survival rate was 96% for translumbar and 89% for transabdominal group, respectively. Sites of metastasis were lung (2 patients) or bone (1 patient) in translumbar group and bone (1 patient) or unknown (1 patient) in transabdominal group. With the favorable prognosis comparable to that of transabdominal radical nephrectomy and the relatively small invasiveness, the current translumbar radical nephrectomy appears to be the choice for the patients with relatively confined small renal cell carcinoma.

Effect of granulocyte colony-stimulating factor on neutropenia in liver transplant recipients with hypersplenism

The authors present details of their initial experience with use of recombinant human granulocyte colony-stimulating factor (rhG-CSF) for preventing neutropenia caused by hypersplenism, and, possibly, for reducing the risk of postoperative infections in pediatric liver transplant recipients. Seven patients with end-stage liver disease, three of whom had severe hypersplenism, underwent living related liver transplantation (LRLT). The rhG-CSF was administered to the latter three patients. Peripheral neutrophil counts decreased immediately after reperfusion (to 1500 +/- 300/microL) in the three patients, and returned to normal with use of rhG-CSF 3 to 10 days after transplantation. The dosage was adjusted to maintain peripheral leukocyte and granulocyte counts above 5,000/microL and 2,000/microL, respectively. This initial clinical trial showed that rhG-CSF administration restores the leukocyte counts of patients who have hypersplenism, without any significant adverse effects, and that rhG-CSF holds promise for reducing the risk of infections after liver transplantation.

Effects of prostaglandins E1, E2 and F2 alpha on contractility and cAMP and cGMP contents in lower urinary tract smooth muscle

Prostaglandin (PG) E1, E2 and F2 alpha contracted smooth muscle strips from male adult rabbit urinary bladder. Contractile responses to each PG were significantly greater in urinary bladder body than in urinary bladder base. The magnitude of contractile response to each PG was F2 alpha > E2 > E1 in both of the bladder body and the bladder base. These contractions were almost completely eliminated by a calcium entry blocker, verapamil but not by atropine, phentolamine, propranolol or tetrodotoxin. PG E1 and E2 significantly relaxed the male rabbit urethral smooth muscle strips, whereas PG F2 alpha contracted the urethral smooth muscle strips. Cyclic adenosine monophosphate (cAMP) but not cyclic guanosine monophosphate (cGMP) increased significantly after administration of PG E1 or E2 in the urethral muscle strip. These results suggest that the regional differences in the magnitude of contractile responses to PG E1, E2 and F2 alpha between the bladder dome and the base and also suggest the contractile differences of PG E1 and E2 for the urinary bladder and the urethra; contractions for bladder and relaxations for urethra. These results also demonstrate that contractions induced by PG E1, E2 and F2 alpha in urinary bladder smooth muscles and by PG F2 alpha in urethral smooth muscles are mainly mediated by calcium influx and that relaxations induced by PG E1 and E2 in urethral smooth muscles are mediated by cAMP but not by cGMP.

[Intra-arterial CDDP and CDDP plus THP-ADM therapy for bladder cancer]

From 1983 to 1988, 20 patients (group A: 3 stage T1, 4 stage T2 and 13 stage T3-4 tumors) with bladder cancer were treated with single injection of CDDP (150-200 mg/body), and 28 patients (group B: 4 stage T1, 9 stage T2 and 15 stage T3-4 tumors) were treated twice with injection of CDDP (100 mg/m2) and THP-ADM (40 mg/m2) mixture from the internal iliac artery. As a rule, one half of the agents was equally given for the both sides, while 75% dose was given to the tumor side to the case with unilateral localized tumors. Then total or partial cystectomy was followed. When residual invasive cancer was pathologically present in operative specimens, patients underwent three to six courses of adjuvant chemotherapy including CDDP. Clinical response rate (CR+PR) to the intra-arterial chemotherapy in group A and B were 39% and 62%, respectively. Pathological response rate (grade 3 and grade 4 by Oboshi and Shimozato classification) were 17% in both group. After total cystectomy, the 2-year cancer specific survival rates of 17 patients in group A and 22 patients in group B were 75% and 59%, respectively. The 2-year cancer specific survival rates of 8 patients in group A and 10 patients in group B with pT3b were 63% and 54%, respectively. No cancer death occurred thereafter in the patients of group A during another three years. The 3-year cancer specific survival rate of 9 patients after partial cystectomy (3 in group A, 6 in group B) was 86%.(ABSTRACT TRUNCATED AT 250 WORDS)

Laryngeal closure at the level of the false cord for the treatment of aspiration

A new procedure for aspiration which closes the larynx at the level of the false cords is reported. This method is not harmful to the vocal folds and maintains arytenoid movement, thus preserving phonatory function. With the advance of the operative technique for aspiration and swallowing rehabilitation, patients who have recovered from aspiration can be helped. Our procedure can be recommended for such cases.

[Relationship between cervical osteophytes and globus sensation--a study based on altered swallowing function]

The swallowing function of ten patients showing marked cervical osteophytes were studied by double contrast pharyngogram and manometric examinations. In five cases in which the pharyngeal clearance was B type according to Shuzaki's classification, a significant increase in the maximal swallowing pressure value on the oral side ipsilateral to the osteophytes was often observed. In five cases in which the pharyngeal clearance showed A + A' type (marked impairment), the frequency of significantly decreased maximal swallowing pressure on the oral side ipsilateral to the osteophytes and abnormal waveforms of the swallowing pressure were high. However, no definite correlation was noted between these changes in swallowing function and osteophyte site. Therefore, there are two possible outcomes of the changes in swallowing function caused by cervical osteophytes: one is a compensatory increase in pharyngeal constriction aimed at maintaining relatively good pharyngeal clearance, the other is impaired pharyngeal constriction and the pharyngeal clearance. These changes in swallowing function would impact on globus sensation.

[Cyclosporine disposition in living related donor partial liver transplant recipients]

We studied the disposition of cyclosporine (CyA) in 8 living related donor partial liver transplant recipients (patient A-H). CyA blood levels were determined by fluorescence polarization immunoassay with specific monoclonal antibody (m-FPIA) and fluorescence polarization immunoassay with non-specific polyclonal antibody (p-FPIA). The ratio of the blood levels of CyA determined by p-FPIA to those by m-FPIA varied significantly, because the levels determined by p-FPIA were influenced by the function of graft liver. Thus, the levels of CyA determined by p-FPIA could not be used for the adjustment of CyA dose. The CyA dose ratios [DR; CyA blood level (mg/l)/dose (mg/kg)] of 3 in 8 patients were relatively large in 1-4 d after the transplant operation, however, it decreased within 2-5 d after the operation. CyA DR gradually increased from 5-8 d after the transplantation, and it reached to a maximum in 10-13 d in 5 patients to whom CyA was administered intravenously over 12 d after transplantation. The average ratio of DR in oral administration to that in intravenous one was about 43%. CyA bioavailability in the patient of living related partial liver transplantation was as usual as that in other organ transplant patient except for cadaveric liver transplant patients. The average DR of intravenous CyA administration in liver transplant recipients was 1.5 times larger than that in bone marrow transplant patients. CyA disposition had large inter-individual and intra-individual variation, and CyA blood level and DR varied in clinical time course at least within 1.5 month after operation. Therefore, it is necessary to measure CyA blood level frequently and to adjust CyA dose.

Distinctive increases in HLA-DR+ and CD8+57+ lymphocyte subsets in Wegener's granulomatosis

Lymphocyte subset abnormalities have been observed in a series of patients diagnosed with Wegener's granulomatosis (WG). Fifteen patients with WG were evaluated for lymphocyte subset abnormalities by two-color immunofluorescence flow cytometry. The WG group showed a decrease in CD4+ cells and an extraordinary increase in HLA-DR+ cells. The average percentages of HLA-DR+ cells of the normal group and WG group were 11.0 +/- 4.0 and 40.5 +/- 13.9% (CD3+HLA-DR+ = 20.3 + 9.4%). Within the CD8 family, CD8+57+, CD8+38+ and CD8+HLA-DR+ cells were markedly elevated. Our findings differ from other series which reported that the lymphocyte subsets in the peripheral blood of patients with WG were normal.

[Laryngeal closure--a simple method and a reversible method for phonation preservation]

Patients with dysphagia due to a disorder in swallowing phase II are candidates for laryngeal closure operation. The operation prevents bolus drainage into the larynx and therefore permits oral feeding. Operative methods in general should be simple and reliable, and furthermore, with regards to this laryngeal closure procedure, they should preferably be reversible to maintain phonatory function, in the event that patients improve swallowing function later on. A laryngeal closure operation which satisfies both conditions has not been previously reported. We present two laryngeal closure operations. One is relatively simple and reliable but irreversible in terms of phonatory function. The other procedure requires more effort but is reversible and therefore allows for preservation of phonatory function. We performed one of these operations on two cases each and obtained good results. 1. Laryngeal closure at the vocal cords. (simple method) The frontal neck skin is incised vertically. The thyroid cartilage perichondrium is incised in the midline and retracted widely on both sides. Then the anterior thyroid lamina is removed at the crico-arytenoid joint. A control hole is opened into the laryngeal lumen by an incision made from the cricoarytenoid membrane to the anterior commissure. The larynx is cut horizontally from the anterior to posterior commissure between the upper and lower lips of the vocal cords. Finally the vocal cords are sutured at the top and bottom of the cut stump. 2. Closure at the false vocal cords. (reversible method for phonation preservation) After the vertical incision has been made, the laryngeal lumen is opened by laryngofissure.(ABSTRACT TRUNCATED AT 250 WORDS)

The effects of gamma-glutamylcysteine ethyl ester, a prodrug of glutathione, on ischemia-reperfusion-induced liver injury in rats

This study was designed to clarify the effects of changes in liver tissue glutathione (GSH) concentration on postischemic liver injury together with the effects of gamma-glutamylcysteine ethyl ester (GCE), a prodrug of GSH, and GSH. Rats were pretreated with GSH (50 mg/kg, i.v.), or GCE (50 mg/kg, i.v.), or untreated. In each rat, liver was isolated, and liver mitochondria were prepared after 2 h of ischemia or 1 h of reperfusion following 2 h of ischemia. Mitochondrial function was measured polarographically. Liver adenine nucleotide concentrations were also determined using high-performance liquid chromatography. Liver tissue GSH, an oxidized form of glutathione (GSSG) concentrations, and activities of GSH peroxidase and GSSG reductase were determined enzymatically. Liver hypoxanthine and xanthine concentrations were determined by HPLC. Liver tissue concentration of lipid peroxide was measured. Leakages of aspartate aminotransferase (AST), alanine aminotransferase (ALT), lactate dehydrogenase (LDH), and adenine nucleotides into the hepatic vein after reperfusion were also measured. Administration of GCE improved the recovery of mitochondrial function and maintained tissue GSH concentration concomitantly. Increases in liver lipid peroxide concentration after reperfusion, and leakage of liver cell enzymes and adenine nucleotides were mitigated by administration of GCE. Administration of GSH itself failed to maintain tissue GSH concentration and had no protective effects. From these results, it is concluded that in the postischemic process, free radical formation might be enhanced, and the radical scavenging system deteriorated. To enhance the radical scavenging system is a possible maneuver to prevent radical-related cell damage associated with reperfusion, because pharmacological reduction of breakdown of ATP to hypoxanthine and xanthine seems to be difficult. GCE maintained liver GSH concentrations and mitigated postischemic liver injury, concomitantly. Clinical use of GCE might be recommended.

Is injectable collagen truly safe?

Most patients have no response to injectable collagen or silicone, but some cases may have positive or 'undersea' (= clinically negative but immunologically positive) response to collagen. From the results of the Macrophage migration inhibition test, the relative immunogenicity was augmented most when we used implants with the following combination. The first immunization was collagen and the second one was collagen with silicone. The augmented antigenicity might be enough to cause an allergic reaction to the patients who had no response to each implant alone.

[Asymptomatic multilocular cystic renal cell carcinoma]

From January 1982 to December 1989, we experienced seven multilocular cystic renal cell carcinomas (MLCRCCs) in 36 asymptomatic renal cancers incidentally diagnosed, and none in 23 symptomatic renal cancers (p less than 0.05). No multiocular cystic nephromas (MLCNs) appeared in either group. Though MLCRCCs have been considered to be, in general, extremely rare, they do occur in asymptomatic renal cancers. A multiloculated renal mass with thick septum discovered in an adult by ultrasonography or CT scan should be suspected as being a MLCRCC rather than a MLCN.

Changes in the glutathione redox system during ischemia and reperfusion in rat liver

After 60 min of reperfusion following 60 min of ischemia, the ischemia-induced decrease in liver tissue adenosine triphosphate (ATP) concentration had recovered by 66%, and full recovery of mitochondrial function--that is, the respiratory control index (RCI) and the rate of oxygen consumption in state-III respiration (ST III O2)--was observed. In contrast, liver tissue ATP concentration had recovered by only 13%, and marked low RCI and ST III O2 were observed after 60 min of reperfusion following 180 min of ischemia. Intermediate results were observed in rats after 60 min of reperfusion following 120 min of ischemia. Liver tissue hypoxanthine and xanthine, substrates of xanthine oxidase, increased ischemic time dependently. Liver tissue concentrations of the reduced form of glutathione (GSH) and the oxidized form of glutathione (GSSG) and activities of glutathione peroxidase and glutathione reductase did not change after 60 min of reperfusion following 60 min of ischemia. In contrast, GSH concentration and glutathione peroxidase activity decreased significantly after 60 min of reperfusion following 180 min of ischemia. Since the glutathione redox system is an important contributor to the scavenging of free radicals after reperfusion following a long time of ischemia, the free radical scavenging ability might decrease in spite of enhancement of free radical generation, which might play an important role in the inhibition of the recovery of tissue ATP concentrations and mitochondrial function.

[Inner ear decompression sickness following a scuba dive]

Inner ear decompression sickness (IEDCS) is one form of Type II decompression sickness. Most cases of IEDCS have been associated with saturation dives, so there are very few reports of occurrence following shallow scuba dives. We present here the case of a diver who suffered from IEDCS following a shallow scuba dive (30m), and was successfully treated by the protocol outlined in U.S. Navy treatment table 6. This case suggests that there is the possibility of occurrence of IEDCS, even following a shallow scuba dive, if proper decompression procedures are not adhered to. In addition, detailed analysis of diving profiles should be used to distinguish the inner ear dysfunction seen in some divers from inner ear barotrauma which may be attributable to IEDCS.

Effect of gonadotropin-releasing hormone pulse frequency on gonadotropin secretion and subunit messenger ribonucleic acids in perifused pituitary cells

Slow frequency GnRH pulses have been proposed to preferentially increase circulating FSH levels by increasing FSH synthesis and pulsatile release. Examination of this proposal using various in vivo models, however, has produced conflicting results. To examine directly the effects of GnRH pulse frequency on the pituitary, we compared the effects of 2.5-nM GnRH pulses administered every 1 h or every 4 h vs. no GnRH, using perifused rat pituitary cells. FSH secretion (total area under the response curve) was 2-fold greater (P less than 0.01) with every hour than with every 4 h GnRH pulses. This difference resulted from the increased number of GnRH pulses and increased (P less than 0.05) interpulse FSH secretion, whereas FSH pulse amplitude was unchanged. FSH beta mRNA levels at the completion of the 11-h perifusion were increased 4.5-fold by GnRH every h (P less than 0.01) and 3.3-fold by GnRH every 4 h (P less than 0.05) above levels in untreated cells. FSH beta mRNA levels were greater (P less than 0.05) at the faster GnRH pulse frequency. Because more frequent stimulation delivered more GnRH during the study, cells were next stimulated with 2.5 nM GnRH every 1 h for nine pulses, 7.5 nM GnRH every 4 h for three pulses to equalize the GnRH dose, or 2.5 nM GnRH every 4 h for three pulses. Interpulse FSH secretion and FSH beta mRNA levels were again greater (P less than 0.05) with every hour than every 4 h GnRH pulses. Interpulse LH secretion, FSH and LH pulse amplitude, and LH beta and alpha-subunit mRNA levels were not different between the groups. GnRH doses of 0.1-10 nM every hour increased FSH and LH pulsatile secretion dose-dependently, but FSH beta, LH beta, and alpha-subunit mRNA levels were similar. In conclusion, our data reveal that reducing the frequency of GnRH pulses from every hour to every 4 h reduces both FSH beta mRNA levels and FSH interpulse secretion, but does not change GnRH-stimulated FSH pulsatile release. We suggest that the finding by others that slow frequency GnRH pulses increase circulating FSH levels under certain experimental conditions in vivo may instead be explained by complex hormonal interactions or changes in FSH clearance.

Effects of testosterone on gonadotropin subunit messenger ribonucleic acids in the presence or absence of gonadotropin-releasing hormone

There is accumulating evidence that the negative feedback actions of testosterone on the pituitary may contribute to the differential regulation of FSH and LH secretion in males. In the present study we measured steady state levels of the mRNAs encoding the gonadotropin subunits in pituitary cell cultures treated with 10 nM testosterone (T) as well as in T-treated pituitary cells perifused with pulses of GnRH to explore further the direct actions of T on the pituitary. T treatment of pituitary cells in monolayer culture for 72 h increased FSH beta mRNA 1.5-fold (P less than 0.05), decreased alpha-subunit mRNA to 45% of the control level (P less than 0.05), and decreased LH beta mRNA to 75% of the control level (P less than 0.05). FSH and uncombined alpha-subunit secretion were increased and decreased by T, respectively, whereas basal LH secretion was unchanged. Treatment with 0.1 nM estradiol, a physiological concentration for males, did not change gonadotropin secretion or subunit mRNA concentrations. Between days 2 and 5 in culture in the absence of steroid treatment, steady state levels of LH beta and alpha-subunit mRNA declined (P less than 0.01) 52% and 61%, respectively, but FSH beta mRNA levels were unchanged. Pulsatile stimulation with 2.5 nM GnRH every 1 h for 10 h increased FSH beta mRNA 2.8-fold (P less than 0.05) and increased (P less than 0.05) alpha-subunit mRNA to 117% of the control level. When cell cultures were pretreated with T for 48 h and then perifused with pulses of GnRH, FSH beta, LH beta, and alpha-subunit mRNA levels were 66%, 74%, and 70% of the value during GnRH alone (P less than 0.05). T treatment also reduced (P less than 0.01) the amplitudes of FSH, LH, and alpha-subunit secretory pulses by 18%, 26%, and 41%, respectively. These data indicate that a portion of the negative feedback action of T is at the pituitary to regulate gonadotropin subunit gene expression. Our data reveal two opposing effects of T on FSH beta mRNA: a stimulatory action, which is GnRH independent, and an inhibitory effect, which is related to the actions of GnRH. These divergent actions of T represent one mechanism through which FSH and LH are differentially regulated.

The cardioprotective effect of gamma-glutamylcysteine ethyl ester during coronary reperfusion in canine hearts

1. The cardioprotective effect of gamma-glutamylcysteine ethyl ester was investigated on ischaemia-reperfusion-induced myocardial damage in anaesthetized dogs. 2. Open chest anaesthetized dogs were divided into four groups: 2 h occlusion of the left anterior descending coronary artery (LAD); 2 h LAD occlusion followed by 1 h reperfusion; 2 h LAD occlusion followed by 1 h reperfusion with administration of gamma-glutamylcysteine ethyl ester (10 mg kg-1 just before reperfusion); 2 h LAD occlusion followed by 1 h reperfusion with administration of GSH (the reduced form of glutathione, 10 mg kg-1 just before reperfusion). 3. After occlusion or reperfusion, heart mitochondria were prepared from the normal area and the occluded or the reperfused area, and mitochondrial function (rate of oxygen consumption in State III, and respiratory control index) was measured polarographically. 4. Mitochondrial GSH and GSSG (the oxidized form of glutathione) concentrations, and activities of glutathione peroxidase and glutathione reductase were measured. 5. Two h of LAD occlusion induced mitochondrial dysfunction with depletion of mitochondrial GSH concentration. One h of reperfusion after 2 h LAD occlusion induced significant mitochondrial dysfunction associated with a marked depletion of mitochondrial GSH concentration. 6. gamma-Glutamylcysteine ethyl ester reduced mitochondrial dysfunction and depletion of mitochondrial GSH concentration after 2 h LAD occlusion and 1 h reperfusion. In contrast, GSH did not prevent depletion of mitochondrial GSH concentration and mitochondrial dysfunction after 2 h LAD occlusion followed by 1 h reperfusion. 7. The activities of glutathione peroxidase and glutathione reductase did not change significantly in each group. 8. One h of reperfusion after 2 h occlusion of LAD induced ventricular arrhythmias. gamma-Glutamylcysteine ethyl ester markedly reduced the development of reperfusion arrhythmias, whilst GSH showed no protective effect.9. Gamma-Glutamylcysteine ethyl ester maintained mitochondrial GSH concentration, prevented reperfusion myocardial damage, and reduced reperfusion arrhythmias.

[BEP (bleomycin, etoposide, cisplatinum) chemotherapy as an induction therapy of advanced extragonadal germ cell tumor]

Five patients with advanced extragonadal germ cell tumor (EGGCT) were treated with cisplatinum + vinblastine + bleomycin (BVP) or cisplatinum + etoposide + bleomycin (BEP) chemotherapy as an induction therapy. All patients had high levels of tumor markers and multiple distant metastasis in poor nutritious conditions. Two patients given BVP therapy died 6 and 9 months after the chemotherapy. By contrast, three patients given BEP therapy achieved complete remission and were surviving longer than one year without any evidences of disease. Granulocytopenic fever was seen soon after the first course of BEP therapy. Prophylactic granulocyte-colony stimulating factor (G-CSF) treatment, enabled two of them to receive full dose chemotherapy without any fever attacks. In conclusion, BEP chemotherapy is effective to EGGCT as well as far advanced testicular tumors and G-CSF treatment is useful for achievement of induction chemotherapy to advanced germ cell tumors.

The primary structure of Aspergillus niger acid proteinase A

The complete amino acid sequence of the acid proteinase A, a non-pepsin type acid proteinase from the fungus Aspergillus niger var. macrosporus, was determined by protein sequencing. The enzyme was first dissociated at pH 8.5 into a light (L) chain and a heavy (H) chain, and the L chain was sequenced completely. Further sequencing was performed with the reduced and pyridylethylated or aminoethylated derivative of the whole protein, using peptides obtained by digestions with Staphylococcus aureus V8 protease, trypsin, chymotrypsin, and lysylendopeptidase. The location of the two disulfide bonds was determined by analysis of cystine-containing peptides obtained from a chymotryptic digest of the unmodified protein. These results established that the protein consists of a 39-residue L chain and a 173-residue H chain that associate noncovalently to form the native enzyme of 212 residues (Mr 22,265). This is, to our knowledge, the first time that such a protein with a rather short peptide chain associated noncovalently has been found. No sequence homology is found with other acid or aspartic proteinases, except for Scytalidium lignicolum acid proteinase B, an enzyme unrelated to pepsin by sequence, which has about 50% identity with the present enzyme. These two enzymes, however, are remarkably different from each other in some structural features.

Amelanotic melanoma metastatic to the epiglottis

Metastasis of melanoma in the head and neck region is often reported but the report of amelanotic melanoma metastatic to the epiglottis is an extremely rare entity. This paper describes a patients previously treated for cutaneous amelanotic melanoma who developed metastatic tumour involving his epiglottis. This legion was successfully excised by a intra-oral approach combined with KTP/532 laser surgery. The paper also describes the diagnostic evaluation, management, operative technique and DNA analysis of this rare case.

Interrelationship between the actions of testosterone and primate Sertoli cell inhibin in the control of gonadotropin secretion by cultured pituitary cells

There is accumulating evidence that the differential regulation of LH and FSH secretion in the male is partly accomplished by the direct actions of testosterone (T) and inhibin on the pituitary. The present study was designed to examine the interaction between T and inhibin, in the presence and absence of GnRH, using dispersed pituitary cells in monolayer culture and cells perifused with pulses of GnRH from intact, 2-week castrated, and castrated T-replaced young adult male rats. The effect of partially purified inhibin from primate Sertoli cell culture medium (pSCI) to suppress basal FSH secretion was similar with pituitary cells from intact and castrated rats. T increased basal FSH secretion in the presence or absence of pSCI but did not alter the dose-dependent suppression of FSH by pSCI with cells from either intact or castrate rats. Castration increased basal FSH and LH secretion, whereas only basal FSH release was increased with cells from T-replaced castrates. T pretreatment increased the action of pSCI to suppress GnRH-stimulated FSH and LH release from perifused pituitary cells. These data indicate that T and inhibin exert opposite but independent effects on basal FSH release. The action of inhibin to suppress basal FSH secretion is not impaired by the absence of T and inhibin subsequent to castration. By contrast, the actions of T and inhibin to suppress GnRH-stimulated gonadotropin secretion are coordinated and interrelated.

Anticataractogenic property of gamma-glutamylcysteine ethyl ester in an animal model of cataract

The anticataractogenic potential of gamma-glutamylcysteine ethyl ester was investigated in model cataracts induced by L-buthionine sulfoximine. Subcutaneous injection of the ester (0.625-2.5 mmol/kg) effectively inhibited cataractogenesis in suckling mice. Treatment of mice with L-buthionine sulfoximine alone resulted in a marked reduction of the glutathione content in the eyes. This deprivation of glutathione was mitigated, to a significant degree, by coadministering gamma-glutamylcysteine ethyl ester. In an experiment with rat lens in culture, gamma-glutamylcysteine ethyl ester was found to elevate the lenticular level of glutathione. These results indicate that gamma-glutamylcysteine ethyl ester is able to permeate across biomembranes and serves as an excellent precursor for glutathione biosynthesis, thereby exerting its anticataractogenic activity.