Mechanisms of intracellular zymogen activation

The pancreatic acinar cell is potentially the initial site of injury that begins the series of events leading to acute pancreatitis. Pathological intrapancreatic zymogen activation occurs in experimental pancreatitis in animals and in human pancreatitis. Intracellular activation has been clearly linked to aberrant zymogen processing in one form of hereditary pancreatitis; in this genetic disease a mutation in cationic trypsinogen may eliminate the degradation of any trypsin activated in the acinar cell. Recent studies have also provided the first direct evidence that trypsinogen activation takes place early in the course of caerulein-induced pancreatitis; parallel studies have used isolated pancreatic acini and conditions that simulate those that cause pancreatitis in vivo to demonstrate that zymogens can be pathologically activated in isolated cells. A unique acinar cell pathway regulates the intracellular proteinase processing of zymogens to their active forms. Stimulating the acinar cell with supramaximal concentrations of cholecystokinin (CCK) or carbamylcholine can activate this pathway. The activation depends on a low pH compartment within the acinar cell and activation of an intracellular serine protease. A marker of trypsinogen processing, the trypsinogen activation peptide (TAP), is generated in acinar cell compartments that do not overlap with secretory granules. This compartment overlaps with a marker of recycling endosomes and lysosomes. Thus, zymogen processing within the acinar cell proceeds in a distinct subcellular compartment and is dependent on a low pH environment and activation of serine proteases.

Transient increases of apoptosis and Bax expression occurring during radiotherapy in patients with invasive cervical carcinoma

BACKGROUND

Apoptosis plays a crucial role in radiation therapy (RT) in various carcinomas. This study was designed to investigate the relation between apoptosis and RT in invasive squamous cell carcinoma (ISCC) of the uterine cervix

METHODS

Thirty-five specimens were obtained from 7 patients with ISCC before and during a fractionated RT. The occurrence of apoptosis was examined by end labeling of DNA gel fractionation and in situ 3' end labeling of DNA. The expression of Bax and Bcl-2 proteins was investigated by immunohistochemical staining.

RESULTS

Autoradiographic analysis revealed that high molecular weight DNA was predominant in the untreated ISCC specimens. However, a ladder-like pattern, characteristic of the apoptotic breakdown of DNA, was identified at doses of 900 cGy and 1980 cGy. At doses >1980 cGy, DNA laddering disappeared without any extensive smearing. Quantitative analysis of low molecular weight fragments of DNA revealed significant increases at doses of 900 cGy and 1980 cGy compared with those before RT and at doses of >1980 cGy. Labeling of DNA in situ indicated that cells undergoing apoptosis increased dramatically at a dose of 900 cGy. However, apoptotic cells decreased at a dose of 3960 cGy. In addition, a large fraction of tumor cells was immunonegative for Bcl-2 before and during RT. By contrast, immunoreactive Bax was observed intensely in many neoplastic cells at doses of 900 cGy and 1980 cGy.

CONCLUSIONS

The current investigation indicates that low doses of RT result in apoptotic cell death in ISCC in association with the increased expression of Bax but not with increased Bcl-2 expression.

Usefulness of diagnostic criteria for aspiration cytology of hepatocellular carcinoma

OBJECTIVE

To establish new criteria for cytodiagnosis of hepatocellular carcinoma by comparing cytologic findings of hepatocellular carcinoma with those of liver cirrhosis.

STUDY DESIGN

Review of cytologic findings of hepatocellular carcinoma on preoperative aspiration biopsy of 31 lesions from 27 patients who underwent surgical resection and comparison of these findings with those of liver cirrhosis in 17 patients.

RESULTS

In the 11 lesions of moderately and poorly differentiated hepatocellular carcinoma, significant cytologic findings included monotonous and abundant cytoplasm, thick cytoplasm, increased nuclear/cytoplasmic ratio, irregular nuclear contours, increased chromatin density, intranuclear vacuoles and naked nuclei. In the 20 lesions demonstrating well-differentiated hepatocellular carcinoma, significant cytologic findings included monotonous and scant cytoplasm, well-defined cytoplasmic borders, thick cytoplasm, eccentric nuclei, increased nuclear/cytoplasmic ratio, thick nuclear membranes and increased chromatin density. We established the criteria for moderately and poorly differentiated hepatocellular carcinoma as including three cytologic parameters: increased nuclear/cytoplasmic ratio, irregular nuclear contours and increased chromatin density. We also established the criteria for well-differentiated hepatocellular carcinoma as including six cytologic parameters: monotonous cytoplasm, scant cytoplasm, well-defined cytoplasmic borders, thick cytoplasm, eccentric nuclei and increased nuclear/cytoplasmic ratio. For all 31 hepatocellular carcinoma lesions, including 27 lesions that were < or = 2 cm in diameter, both sensitivity and specificity were 100% by concurrently employing both criteria.

CONCLUSION

The new criteria for cytodiagnosis we established were useful for differentiating hepatocellular carcinoma from liver cirrhosis. In particular, our criteria ensured appropriate diagnostic accuracy for well-differentiated hepatocellular carcinoma.

Anterior cruciate ligament reconstruction and physiological joint laxity: earliest changes in joint stability and stiffness after reconstruction

Physiological joint laxity is an important element of normal knee joint function, providing smooth joint movement. However, the objective evaluation of post-operative results after knee ligament surgery is usually based primarily on stability and range of motion, and joint laxity has been ignored. In this study, we measured the joint stiffness of 82 knees undergoing anterior cruciate ligament (ACL) reconstruction with the Leeds-Keio artificial ligament, before the operation, immediately after the operation, and finally when the full range of motion was achieved postoperatively; changes in joint laxity after the ACL reconstruction were investigated. Before the operation, joint laxity was greater than that of the normal side (P < 0.01), but immediately after the operation it diminished compared not only with that observed preoperatively, but also with that of the normal side. When the full range of motion was achieved, joint laxity was lower than that observed immediately after the operation (P < 0.01), but still remained higher than that of the normal side (P < 0.01). In other words, stability was achieved, but joint laxity was diminished through the operation. In this series, a stiffer artificial ligament than the natural ACL was used, and maximum tension was applied during the operation, aiming at better stability, but this may cause diminution of joint laxity.

Patterns of diabetic macular edema with optical coherence tomography

PURPOSE

We report cross-sectional images of diabetic macular edema and correlation between tomographic features and visual acuity with best correction by means of optical coherence tomography.

METHOD

In a prospective study, optical coherence tomography was performed in 59 eyes of 42 patients with diabetic macular edema and in 10 eyes of 10 normal control subjects.

RESULTS

Optical coherence tomography showed three patterns of structural changes in diabetic macular edema: sponge-like retinal swelling (52 [88%] of 59 eyes), cystoid macular edema (28 [47%] of 59 eyes), and serous retinal detachment (9 [15%] of 59 eyes). Some eyes had more than one pathologic change. Retinal swelling was more pronounced in the outer rather than the inner retinal layers. Cystoid macular edema was located mainly in the outer retinal layers. In eyes with long-standing cystoid macular edema, cystoid spaces had fused, resulting in a large cystoid cavity involving almost the entire retinal layer. Hard exudates were seen as highly reflective areas located in the outer retinal layers. The retinal thickness at the central fovea and the visual acuity with best correction showed an intermediate negative correlation in eyes without cystoid macular edema (correlation coefficient: -0.61, P < .01).

CONCLUSIONS

Diabetic macular edema involved three structural changes, including sponge-like retinal swelling (88%), cystoid macular edema (47%), and serous retinal detachment (15%). Visual acuity with best correction moderately correlated with retinal thickness regardless of the different tomographic features.

Apoptosis and the expression of Bax and Bcl-2 in squamous cell carcinoma and adenocarcinoma of the uterine cervix

BACKGROUND

Apoptosis plays a crucial role in the suicide and turnover of cells in various tumors. This study was designed to investigate the relation between apoptosis and the histologic types of cell in invasive cervical carcinoma.

METHODS

Cervical tissues were obtained from 19 patients with invasive squamous cell carcinoma (ISCC), 9 patients with invasive endocervical adenocarcinoma (IEAC), and 15 patients with myoma uteri (which were used as controls). Each tissue was rapidly frozen and/or fixed in Bouin's solution. The occurrence of apoptosis was examined by end labeling of DNA with (alpha-32P)dideoxyATP and electrophoretic fractionation and by end labeling of DNA in situ with digoxigenin-dideoxyUTP. The expression of Bcl-2 and Bax proteins was examined by immunohistochemical staining with appropriate antibodies.

RESULTS

Autoradiographic analysis revealed that high molecular weight DNA was predominant in the normal cervical epithelium (NCE) and in ISCC. However, a ladder-like pattern of DNA fragments, characteristic of the apoptotic breakdown of DNA, was identified in IEAC. Quantitative analysis of low molecular weight fragments of DNA revealed a significant increase in IEAC but not in ISCC compared with NCE. Labeling of DNA in situ indicated that cells undergoing apoptosis were predominant among the neoplastic cells of IEAC. However, no apoptotic cells were noted in ISCC, with the exception of cells in some tumor nests. A large fraction of IEAC and ISCC was immunonegative for Bcl-2. Although the expression of Bax was detected weakly in a small fraction of ISCC, strong expression of Bax was observed in all cases of IEAC.

CONCLUSIONS

Apoptosis appears to occur in the cancerous cells of invasive adenocarcinoma of the uterine cervix in association with a high level of expression of Bax but not of bcl-2.

Therapeutic effect of oral levofloxacin, ciprofloxacin, and ampicillin on experimental murine pneumonia caused by penicillin intermediate Streptococcus pneumoniae for which the minimum inhibitory concentrations of the quinolones are similar

The therapeutic efficacy of oral treatment with levofloxacin, ciprofloxacin, and ampicillin on an experimental pneumonia caused by the penicillin-intermediate Streptococcus pneumoniae for which the minimum inhibitory concentrations (MICs) of the quinolones are similar was assessed in immunocompetent CBA/J mice. Levofloxacin exhibited a dose-dependent therapeutic effect, and achieved complete eradication of S. pneumoniae from the lungs at 120 mg/kg/day, whereas ciprofloxacin and ampicillin were hardly effective at all. A pharmacokinetic study in infected mice revealed good oral absorption and lung tissue penetration of levofloxacin (peak lung concentration: 5.95 microg/g of lung), low oral absorption of ciprofloxacin in spite of a good penetration into lung tissue (1.10 microg/g of lung), and low lung tissue penetration of ampicillin despite rather good oral absorption (1.71 microg/g of lung). In an in vitro time-kill study that simulated the peak concentration of drugs in the lungs of infected animals, the killing activity of levofloxacin was found to be greater than that of ciprofloxacin and ampicillin. These data suggest that the therapeutic efficacy of levofloxacin in this model is attributable to both its potent bactericidal activity and excellent pharmacokinetic profile.

Inhibition by D-limonene of gastric carcinogenesis induced by N-methyl-N'-nitro-N-nitrosoguanidine in Wistar rats

The effect of prolonged oral administration of D-limonene on gastric carcinogenesis induced by N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) and on the labeling and apoptotic indices of gastric cancers were investigated in Wistar rats. After 25 weeks of the carcinogen treatment, rats were given chow pellets containing 1% or 2% limonene. In week 52, long-term oral administration of 2%, but not 1%, limonene significantly decreased the incidence of gastric cancers. Limonene also significantly decreased the labeling index and significantly increased the apoptotic index of gastric cancers. No K-ras mutations were detected in gastric cancers induced by MNNG in either group. These findings indicate that limonene inhibits the development of gastric cancers through increased apoptosis and decreased DNA synthesis of gastric cancers, but not through ras oncoprotein plasma membrane association.

Investigation of the most effective provocation test for patients with coronary spastic angina: usefulness of accelerated exercise following hyperventilation

This study sought to compare the clinical usefulness of the hyperventilation plus cold stress test or the hyperventilation combined with accelerated exercise test with other single tests in patients with coronary spastic angina. The study examined 24 patients (23 men, mean age 66 years) with angiographically confirmed coronary spastic angina and less than 50% stenosis. Moreover, none had spontaneous ST segment elevation before the study. Under no medication for at least 24 h prior, 4 procedures were performed from 09.00 h to 11.00 h: (i) a hyperventilation test for 5 min (HV(5)); (ii) HV(5) combined with a cold stress test for the last 2 min (HV(5)+CS(2)); (iii) a treadmill exercise test based on Bruce's protocol (TM(3)); and (iv) a treadmill exercise test accelerated at 1 min intervals according to Bruce's protocol immediately after HV(5) (HV(5)+TM(1)). The rate of appearance of chest pain and ischemia-induced ECG changes due to HV(5)+TM(1) were significantly higher than the other 3 tests. HV(5)+CS(2) was not superior to HV(5) alone. The incidence of provoked ST segment elevation due to HV(5)+TM(1) was higher than with the other 3 procedures. Thus, in patients with coronary spastic angina, no spontaneous ST segment elevation and near normal coronary arteries, HV(5)+CS(2) was no more useful than HV(5) alone. It is recommended that the newly designed HV(5)+TM(1) combination test be used for documenting evidence of ischemia in patients with coronary spastic angina, low disease activity and near normal coronary arteries.

Extensive post-traumatic ossification of the patellar tendon. A report of two cases

Two men, aged 21 and 50 years, were seen with ossification of the patellar tendon after injury to the knee in adolescence. They complained of pain and had patella alta. Large bony masses were excised from below the affected patellae. The patellar tendon was then reconstructed using a Leeds-Keio ligament. The results at six and ten years, respectively, were good, with neither patient having pain or an extension lag.

[Circadian rhythm of parasympathetic nervous function in asthmatic children]

We examined the circadian rhythm of parasympathetic nervous function in asthmatic children. The subjects were 80 patients with asthma (mild 54 patients, moderate 15 patients and severe 11 patients) and 90 individuals in healthy children. All the patients underwent 24-electrocardiography in normal condition. We measured the %RR50 for hour and analyzed the rhythm using the single cosine fitting method, comparing the values of the Amplitude, the MESOR and the Acrophase in terms of the therapy and also the severity of asthma. Circadian rhythm disappeared in 9 of the 80 asthmatic children and was observed in all the individuals in the healthy children. The value of MESOR was lower in the asthmatic children than in the healthy children. There was no significant difference between the different severity or therapies in each group. In some asthmatic children, the circadian rhythm of parasympathetic nervous function disappeared, the parasympathetic nervous function was low in remission. It is suggested that the disorder of biologic rhythm is related to the pathogenesis of asthma.

Three cases with familial adenomatous polyposis diagnosed as having malignant lesions in the course of a long-term trial using docosahexanoic acid (DHA)-concentrated fish oil capsules

The inhibitory effect of n-3 polyunsaturated fatty acids on human colorectal cancer has been speculated on from epidemiological data and animal studies. We conducted a long-term trial of docosahexanoic acid (DHA)-concentrated fish oil capsules for patients in a high-risk group for colorectal cancer. During this trial, we experienced three patients with familial adenomatous polyposis (FAP) diagnosed as having malignant lesions. Three patients with FAP and two patients with multiple (more than 30) colorectal polyps were administered DHA-concentrated fish oil capsules_Hlk427554600[2.2 g of DHA and 0.6 g of eicosapentanoic acid (EPA) per day] for one or two years. Compliance with DHA-concentrated fish oil capsules was more than 90% in four patients and 61% in one patient. A marked increase or decrease in the number of polyps was not observed. Three patients with FAP developed endometrial cancer after 12 months, colon cancer after 24 months and lung cancer after 12 months, respectively. All cancers were diagnosed at an early stage and were resected curatively. We thought that the possibility of developing cancer from the long-term administration of fish oil capsules to patients with FAP needs to be investigated further, and that we should report these cases.

Codistribution of TAP and the granule membrane protein GRAMP-92 in rat caerulein-induced pancreatitis

The pathological activation of zymogens within the pancreatic acinar cell plays a role in acute pancreatitis. To identify the processing site where activation occurs, antibodies to the trypsinogen activation peptide (TAP) were used in immunofluorescence studies using frozen sections from rat pancreas. Saline controls or animals receiving caerulein in amounts producing physiological levels of pancreatic stimulation demonstrated little or no TAP immunoreactivity. However, after caerulein hyperstimulation (5 micrograms. kg-1. h-1) for 30 min and the induction of pancreatitis, TAP immunoreactivity appeared in a vesicular, supranuclear compartment that demonstrated no overlap with zymogen granules. The number of vesicles and their size increased with time. After 60 min of hyperstimulation with caerulein, most of the TAP reactivity was localized within vacuoles >/=1 micrometer that demonstrated immunoreactivity for the granule membrane protein GRAMP-92, a marker for lysosomes and recycling endosomes. Pretreatment with the protease inhibitor FUT-175 blocked the appearance of TAP after hyperstimulation. These studies provide evidence that caerulein hyperstimulation stimulates trypsinogen processing to trypsin in distinct acinar cell compartments in a time-dependent manner.

Zymogen proteolysis within the pancreatic acinar cell is associated with cellular injury

The pathological activation of digestive zymogens within the pancreatic acinar cell probably plays a central role in initiating many forms of pancreatitis. To examine the relationship between zymogen activation and acinar cell injury, we investigated the effects of secretagogue treatment on isolated pancreatic acini. Immunofluorescence studies using antibodies to the trypsinogen-activation peptide demonstrated that both CCK (10(-7) M) hyperstimulation and bombesin (10(-5) M) stimulation of isolated acini resulted in trypsinogen processing to trypsin. These treatments also induced the proteolytic processing of procarboxypeptidase A1 to carboxypeptidase A1 (CA1). After CCK hyperstimulation, most CA1 remained in the acinar cell. In contrast, the CA1 generated by bombesin was released from the acinar cell. CCK hyperstimulation of acini was associated with cellular injury, whereas bombesin treatment did not induce injury. These studies suggest that 1) proteolytic zymogen processing occurs within the pancreatic acinar cell and 2) both zymogen activation and the retention of enzymes within the acinar cell may be required to induce injury.

Clear demonstration of carcinoma of the ampulla of Vater with ultrasonography

We present a non-icteric case, in which an ampullary polypoid lesion was clearly demonstrated by ultrasonography, suggesting carcinoma of the ampulla of Vater. The lesion was a 3 cm in diameter, spherical tumor with a polypoid surface, and internal hyperechogenicity. The patient underwent a curative pylorus-preserving pancreaticoduodenectomy.

Effect of increased physical activity on bone mineral density in postmenopausal osteoporotic women

The effect of increased physical activity on bone mineral density (BMD) of the lumbar vertebrae was examined in postmenopausal osteoporotic women. Thirty-five postmenopausal women, aged 53-77 years, whose BMD in the lumbar vertebrae (L2-L4) measured by dual energy x-ray absorptiometry (Norland XR-26) was below (> 30%) the young adult mean, were divided into two groups: a control group of 20 women and an exercise group of 15 women. The physical exercise consisted of daily outdoor walking and gymnastic training performed for 12 months. During the study period, all subjects were treated with calcium lactate, 2.0 g, and 1 alpha-hydroxyvitamin D3, 1 microgram, daily. Initial L2-L4 BMD was 0.611 +/- 0.045 (mean +/- SEM) g/cm2 in the control group and 0.606 +/- 0.066 g/cm2 in the exercise group (NS). In the control group, the BMD changes were -0.54 +/- 0.58% (mean +/- SEM) at 6 months and +1.00 +/- 1.29% at 12 months, compared to the baseline (P = 0.3424, by oneway ANOVA). In the exercise group, however, the changes were +1.78 +/- 0.90% and +4.48 +/- 0.93%, respectively (P = 0.0305, by two-way ANOVA). These data suggest that increased physical activity consisting of daily outdoor walking and gymnastic training can be useful in increasing lumbar BMD in postmenopausal osteoporotic women on calcium and vitamin D3 supplementation.

A miniature probe enables clear demonstration of the cystic duct during laparoscopic cholecystectomy

We performed intraoperative ultrasonography with a miniature probe to explore the biliary anatomy, especially the cystic duct, during laparoscopic cholecystectomy. By using this radial-type probe introduced into a hard metal sheath with a balloon at the end, the plane containing Calot's triangle can be scanned easily when the gallbladder is extracted to the right side, thereby facilitating the identification of the cystic duct as well as the common ducts. In 30 cases, no common duct stone was found and the cystic duct was clearly identified. This radial-type miniature probe can be used to locate the cystic duct and avoid inadvertant incision or division of the common ducts.

Impingement after total knee arthroplasty caused by cement extrusion and proximal tibiofibular instability

A 57-year-old patient with rheumatoid arthritis showed posterolateral impingement after total knee arthroplasty. The radiographs showed bone cement extrusion posterolateral to the tibial tray. Arthrotomy through a posterolateral approach revealed that the impingement was caused not only by cement extrusion against the fibular head but also by proximal tibiofibular joint instability. It was speculated that rheumatoid arthritis had caused proximal tibiofibular instability, active knee motion had caused fibular head shift by tension of biceps femoris and the fibular head had been impinged on the extruded cement. In cementing the tibial tray, especially in a rheumatoid patient, it is of paramount importance to take caution against posterolateral cement extrusion in order to minimize the risk of fibular head impingement during total knee arthroplasty.

MJ347-81F4 A & B, novel antibiotics from Amycolatopsis sp.: taxonomic characteristics, fermentation, and antimicrobial activity

Strain MJ347-81F4 has been found to produce two new cyclic thiazolyl peptide antibiotics, components A and B. Taxonomic studies including morphological and physiological characteristics and chemical analysis of whole cells of the producing strain revealed this microorganism to belong to genus Amycolatopsis, and so we designated the strain Amycolatopsis sp. MJ347-81F4. After 10 to 12 days of fermentation, most of the antibacterial activity was present mainly in the mycelial cake and reached its maximum level. In comparison with reference compounds, A as the major component showed excellent in vitro activity against gram-positive bacteria including highly methicillin-resistant Staphylococcus aureus (MRSA) and Enterococcus faecalis with MICs in the range of concentration of 0.006 to to approximately 0.1 microg/ml. The results on the antimicrobial activity against thiazolyl peptide-resistant mutants of Bacillus subtilis NRRL B-558 indicated that the possible molecular target of MJ347-81F4 component A might be the 50S subunits of the ribosome, the inactivation of which would inhibit protein synthesis.