A sulfonated capillary that gives reproducible migration times for capillary zone electrophoresis and micellar electrokinetic chromatography

To obtain reproducible migration times and rapid analyses of analytes, sulfonate groups were chemically introduced to the inner wall of untreated fused-silica capillary with 2-(4-chlorosulfonylphenyl)ethyltrichlorosilane. The sulfonated capillary showed relatively constant electroosmotic mobility which was greater than that obtained by an untreated fused-silica capillary over the pH range studied (pH 2-9). In both CZE and MEKC, the RSDs of the migration times of analytes with the sulfonated capillary were less than 0.2% which were significantly lower than those obtained with an untreated fused-silica capillary (0.5-3.5%). When BGE were set at pH 7.0 for CZE and MEKC, the analysis times with the sulfonated capillary were about half those obtained with an untreated fused-silica capillary. These results indicate that the sulfonated capillary can provide highly reproducible and rapid analyses in CE.

Evaluation of the surface charge properties of porous graphitic carbon stationary phases treated with redox agents

The effect of treatment of porous graphitic carbon (PGC) stationary phases with hydrogen peroxide and with sodium sulfite on the retention behavior of analyte compounds has been investigated using benzene, aromatic sulfonate ions, and benzyltrialkylammonium ions as model compounds. It is shown that the retention times of the cationic analytes are increased by treating the PGC column with the reducing agent, while decreased by treating it with the oxidizing agent. On the other hand, the retention times of the anionic analytes are decreased by treating the column with the reducing agent, while increased by treating it with the oxidizing agent. The effect of the redox treatment on the retention of benzene is negligibly small. The investigation of the ion-exchange property of the PGC packings have shown that PGC has anion-exchange property and the anion-exchange capacity is decreased by treating PGC with the reducing agent, whereas it is increased by treatment with the oxidizing agent. This means that the modification of the retention selectivity of the PGC stationary phases with redox treatment can be interpreted in terms of the change of the surface charge. The mechanism of chemical modification of the PGC stationary phase with redox treatment is discussed on the basis of the experimental results obtained on the ion-exchange capacity and the redox activity.

[The optimal procedure for chylothorax after operation for thoracic esophageal cancer; reasonable approaches to the thoracic duct from the point of view of routes for esophageal replacement]

In general, chylothorax after esophagectomy with lymph node dissection under thoracotomy is a rare postoperative complication. We report a 71-year-old man who developed chylothorax following esophagectomy and 3-field lymph node dissection together with reconstruction using stomach through the posterior mediastinum, and discuss ideal approaches that are less invasive and make it possible to provide better exposure of the thoracic duct. In selecting the ideal approach, the most important thing is differences in routes for esophageal replacement. The anatomical relation between the location of a conduit adopted for reconstruction of the resected esophagus and the thoracic duct should be considered in each case. In the case of the retrosternal or antesternal route, a video-assisted thoracoscopic approach allows for easy detection of the thoracic duct while reducing surgical invasiveness, because there is no conduit in the posterior mediastinum. On the other hand, a conduit interrupts the visual field of thoracoscopy in the case of the posterior mediastinal or intrathoracic route. Drawing up of a conduit to gain a good operative field involves some risks in protection of the vascular pedicle. Therefore, a transabdominomediastinal approach is an optimal option. With this approach, we could easily find the thoracic duct and directly ligate it just cranial to the hiatus, resulting in a remarkable decrease in discharge through the thoracic drainage tube. In addition, we present an intelligible intraoperative photograph.

[Postintubation tracheal stenosis; problems associated with choice of management]

We experienced a case with tracheal stenosis due to postintubation damage, or so-called cuff stenosis. A 50-year-old man who attempted suicide by pounding nails into his head and chest using carpenter's tools was treated by endotracheal intubation and immediately underwent emergency surgery in July 2000. The patient was placed on artificial ventilation with oral endotracheal intubation, and a tracheostomy was performed 4 days after the operation. After that, his respiration recovered and he was weaned from the respirator. He was discharged 22 days after surgery with no respiratory symptoms. Two days after discharge, he complained of wheezing and dyspnea. Medical examination revealed that the cervical trachea had a severe circumferential stenosis 2.5 cm from the second tracheal cartilage. On retrospective inspection, the region of stenosis was compatible with the cuff site of the endotracheal tube used for the emergency operation. At first we tried nonoperative treatment, considering his mental state. However, we found that surgical treatment was ultimately necessary. A 2.5 cm sleeve resection of the trachea (5 tracheal cartilage rings) was performed, followed by end-to-end suture using 21 stitches with 4-0 MEDIFIT C thread. Pathologically, the surgical specimen showed degeneration and necrosis of tracheal cartilage with excessive growth of granulation tissue. These findings revealed that the etiologic basis of the tracheal stenosis was attributed to pressure necrosis by the cuff. The postoperative course was uneventful. Sixteen months after the surgery, the granulation tissue had not recurred, and problematic stenosis was not visible in the trachea. In this report, we discussed a reasonable management of postintubation tracheal stenosis. Tracheoplasty has been proposed as the most reliable method for treating tracheal stenosis. However, the best treatment in each case is still somewhat controversial because various nonoperative treatment methods are recently available, including laser phototherapy, argon plasma coagulation, mechanical dilatation, stent replacement, and drug treatment. Therefore, it is very important to judge properly the absolute indication for surgical treatment. If granulations are removed successfully by the above-described nonoperative methods, attempts at repair lead only to regrowth of granulation tissue as long as there is necrotic tracheal cartilage. Thus, the determinant of treatment methods is whether postintubation damage extends to tracheal cartilage or not. For now, there is no accurate diagnostic study for viability of cartilage preoperatively. In the literature, symptoms due to airway stenosis occurred rapidly within one month in the case of patients with necrosis of tracheal cartilage. We concluded that the period between extubation and development of symptoms is very informative in the management of postintubation tracheal stenosis. Surgical approaches should be selected for a patient with a rapid and progressive course after extubation when the patient can tolerate it.

Relapse patterns of localized non-Hodgkin's lymphoma of the head and neck after clinical remission: results of a strict follow-up procedure

BACKGROUND

No effective follow-up strategy for non-Hodgkin's lymphoma (NHL) has been identified to date. The aim of this study was to assess the value of a strict follow-up procedure in patients with NHL after they showed clinical remission.

METHODS

One hundred and twenty-one patients with localized NHL of the head and neck who had achieved clinical remission after radiation therapy and/or chemotherapy were followed with a strict follow-up strategy (consisting of a schedule of frequent office visits, imaging studies, and blood tests, even if the patient was asymptomatic).

RESULTS

Thirty-nine patients relapsed after remission. Twenty-two (56.4%) of the relapses were associated with symptoms. In the 17 patients with asymptomatic relapses (43.6%), an abnormal physical examination result initially indicated relapse in 10 patients. The other tests that initially indicated relapse included scheduled computed tomography scans (3 patients), scheduled gallium scans (2 patients), and serum lactate dehydrogenase levels (2 patients). According to the Ann Arbor stage at relapse, 72.7% of the patients with symptomatic relapses were stage III or IV, while 70.6% of the patients with asymptomatic relapses were stage I or II.

CONCLUSIONS

These results indicate that a strict follow-up procedure is effective in detecting asymptomatic relapses, which generally involve a smaller tumor load than symptomatic relapses.

[An elderly woman with breast cancer and multiple liver metastasis that responded well to combination therapy of fadrozole and tamoxifen]

Few reports suggest a clinical benefit from combination treatment of fadrozole and tamoxifen for advanced breast cancer in elderly patients. We report the case of an 82-year-old breast cancer patient with multiple liver metastasis. After mastectomy, combination treatment of fadrozole and tamoxifen was added. Two months after the start of this treatment, there was a remarkable reduction in the size of metastatic lesions that continued over 6 months. CT examination revealed the largest lesion was reduced from 8.0 cm to 5.0 cm in largest diameter. The other two lesions were reduced from 3.0 cm to 2.0 cm. The reduction rate was 36%, indicating PR in the Response Evaluation Criteria in Solid Tumors (RECIST). The tumor marker CEA was remarkably reduced from 318 to 85 (ng/ml), and CA15-3 was reduced from 430 to 150 (U/ml). Tumor marker reduction continued over the 6 months corresponding to CT findings. No adverse effect was experienced. This combination therapy was useful and safe against metastatic breast cancer in a patient over 80 years of age.

Invasive thymoma associated with lung cancer: report of a case

We report herein a case of invasive thymoma simultaneously associated with lung cancer. A 64-year-old man presented with a cough and anterior chest pain, and preoperative examinations revealed an anterior mediastinal tumor as well as lung cancer. The patient underwent a total thymectomy, partial resection of the right lung, left lower lobectomy, and mediastinal lymph node dissection, followed by radiotherapy. Although it is well known that thymomas may be accompanied by nonthymic cancers, invasive thymomas occurring coincidentally with lung cancer are rarely reported in Japan. This case is very interesting in its relation to the oncogenesis of thymomas.

Stabilizing and solubilizing effects of sulfobutyl ether beta-cyclodextrin on prostaglandin E1 analogue

PURPOSE

Parent cyclodextrins are known to accelerate the degradations such as dehydration and isomerization of E-type prostaglandins in neutral and alkaline solutions. The objective of this study was to attempt the stabilization and solubilization of E1-type prostaglandin analogue in aqueous solution by biocompatible cyclodextrin derivatives.

METHODS

The interaction of an E1-type prostaglandin, methyl 7-[(1R,2R,3R)-3-hydroxy-2-[(E)-(3S)-3-hydroxy-4-(m-methoxymethylphenyl)1-butenyl]-5-oxocyclopentyl]-5-thiaheptanoate (MEester) with cyclodextrins (CyDs) was studied by spectroscopies and the solubility method. The degradation of MEester was monitored by high-performance liquid chromatography.

RESULTS

1H-nuclear magnetic resonance spectroscopic studies indicated that MEester forms 1:1 inclusion complexes with alpha-, beta-, and gamma-CyDs in solutions, where alpha-CyD interacts with the a-side chain containing methyl ester moiety of the drug, whereas beta- and gamma-CyDs preferentially include around the five-membered ring and both side chains of the drug. Parent alpha-CyD and hydrophilic derivatives, such as 2-hydoxypropyl-alpha- and -beta-CyDs, sulfobutyl ether beta-CyD (SBE-beta-CyD) and maltosyl beta-CyD showed higher solubilizing abilities against MEester over parent beta- and gamma-CyDs. SBE-beta-CyD and 2,6-dimethyl-beta-CyD (DM-beta-CyD) significantly decelerated the degradation of MEester, particularly the base-catalyzed dehydration, in neutral and alkaline solutions, whereas other CyDs accelerated the degradation. The acid-catalyzed degradation of MEester (pH < 3) was decelerated by the addition of CyDs, especially alpha-CyD.

CONCLUSIONS

SBE-beta-CyD with low hemolytic activity and low toxicity is useful as a pharmaceutical carrier for the preparation of injectable MEester, because of its higher stabilizing and solubilizing effects on MEester. Furthermore, SBE-beta-CyD can be useful as a stabilizing agent for drugs, that are subject to base-catalyzed degradations, probably because of the electric repulsion between anionic charges of the sulfobutyl moiety and catalytic anionic species such as hydroxide ion.

[Reirradiation with brachytherapy for recurrent tongue cancer after initial brachytherapy]

The purpose of this study was to assess the efficacy of reirradiation with brachytherapy in the treatment of patients with tongue cancer that had recurred after initial brachytherapy. A retrospective analysis was performed in 12 patients with tongue cancer treated by reirradiation with brachytherapy using rigid linear sources such as the 226Ra-needle or 192Ir-hairpin at Kyushu University Hospital from 1978 to 1998. The patients included 8 men and 4 women, who ranged in age from 30 to 69 years (mean, 52 years). At the time of reirradiation, 7 patients had stage I cancer, and 5 had stage II cancer, according to the UICC (1997) classification. The median follow-up time of the surviving patients was 92 months. The 5-year relapse-free and cause-specific survival rates were 31% and 64%, respectively. The 5-year cause-specific survival rate varied according to the interval between the first and second course of brachytherapy and was 25% for intervals of less than 12 months and 83% for intervals of more than 12 months. Only 4 patients with local recurrence were recognized after their second course of brachytherapy. Among the 6 patients who survived more than 2 years after reirradiation without local recurrence, symptomatic complications such as soft tissue necrosis and minimal bone necrosis were found in 3 patients, but these side effects were not serious enough to require surgery. Reirradiation with a second course of brachytherapy may be useful in the treatment of patients with tongue cancer that recurs more than 12 months after initial brachytherapy.

Enhanced absorption of insulin and (Asu(1,7))eel-calcitonin using novel azopolymer-coated pellets for colon-specific drug delivery

The objective of this study was to estimate colon-specific delivery of insulin and (Asu(1,7))eel-calcitonin using novel azopolymer-coated pellets. In vitro drug-release experiments from the azopolymer-coated pellets containing fluorescein isothiocyanate dextran (MW 4400; FD-4) were carried out by the Japanese Pharmacopoeia (J.P.) XIII rotating basket method with some slight modifications. Little release of FD-4 from the pellets was observed in phosphate buffered saline. However, the release of FD-4 was markedly increased in the presence of rat cecal contents. The intestinal absorption of insulin and (Asu(1,7))eel-calcitonin after oral administration of the azopolymer-coated pellets containing these peptides with camostat mesilate was evaluated by measuring the hypoglycemic and hypocalcemic effects, respectively. A slight decrease in plasma glucose levels was observed following the oral administration of these pellets containing 12.5 IU of insulin compared with the same dose of insulin solution. Camostat mesilate, a protease inhibitor that is incorporated with insulin in these pellets, further decreased the plasma glucose levels in a dose-dependent manner. Similar results were also obtained with the oral administration of pellets containing (Asu(1,7))eel-calcitonin. These findings suggest that azopolymer-coated pellets may be useful carriers for the colon-specific delivery of peptides including insulin and (Asu(1,7))eel-calcitonin.

[Effectiveness of intra-arterial infusion chemotherapy for solitary bone metastasis from lung cancer with radiotherapy--a case report]

There have been few reports on intra-arterial infusion chemotherapy for metastatic bone cancer because the bone metastasis is multiple in almost all cases. However, selective intra-arterial infusion chemotherapy is thought to be more effective than systemic chemotherapy for solitary bone metastasis. The patient was a 47-year-old man who had been diagnosed with solitary metastasis of the right knee joint from lung cancer on the basis of various imaging studies and biopsy. The metastatic bone cancer showed rapid growth with systemic inflammatory response, and the patient's general condition became progressively worse. Therefore, radiotherapy alone consisting of 3 Gy of fraction x 5 fractions/week was initiated, but the metastatic lesion was a progressive disease (PD) at the middle point of radiotherapy (24 Gy), and we had no choice but to alter the therapy. Angiography showed dense tumor staining, so intra-arterial infusion chemotherapy was contemplated. Subsequently 15 mg/body of CDDP was administered persistently 5 days a week through a catheter placed in the right femoral artery that had been introduced via the left femoral artery. After 8 courses of this therapy (total dose 600 mg), the metastatic bone cancer was remarkably reduced in size and showed nearly a complete response (CR) on CT scan. This result suggests that intra-arterial infusion chemotherapy is very effective if there is only one bone metastasis lesion.

[A case of Marie-Bamberger syndrome caused by growth hormone-producing lung cancer: problems associated with peri- and postoperative management of patients with growth hormone-producing tumors from the standpoint of the "second attack" theory]

Marie-Bamberger syndrome is identical to pulmonary hypertrophic osteoarthropathy, and the causative factors have not been thoroughly clarified yet. Therefore, further studies of each case would seem to be useful to shed some light on the pathogenesis. We reported a 48-year-old man with primary lung cancer associated with clubbing of the fingers and hypertrophic osteoarthropathy. Chest CT portrayed a 10 x 6.5-cm bulky mass with central necrosis in the left upper lobe. The serum level of growth hormone (GH) showed about a twenty-fold increase over the normal upper limit. With the emergence of SIRS (Systemic Inflammatory Response Syndrome), the patient's general condition took a downhill course. We considered this state to be an oncological emergency and performed a semi-urgent operation. Immunohistochemical evaluation revealed a poorly differentiated adenocarcinoma with GH production. After treatment, the serum level of GH normalized and the clubbing and the periosteal changes of the bones resolved, which suggests that GH plays an etiologic role in Marie-Bamberger syndrome. Recent studies have indicated that GH has immunostimulatory effects. From the standpoint of the "second attack" theory, surgical stress seems to act on the immune system already activated by GH (so called "priming") in the form of a second attack, and trigger an excessive inflammatory response leading to postoperative organ injury in patients who suffer from GH-producing tumors. Thus, we should recognize this immanent risk and perform peri- and postoperative management for patients with GH-producing tumors.

Enhanced absorption of insulin and (Asu(1,7))eel-calcitonin using novel azopolymer-coated pellets for colon-specific drug delivery

The objective of this study was to estimate colon-specific delivery of insulin and (Asu(1,7))eel-calcitonin using novel azopolymer-coated pellets. In vitro drug-release experiments from the azopolymer-coated pellets containing fluorescein isothiocyanate dextran (MW 4400; FD-4) were carried out by the Japanese Pharmacopoeia (J.P.) XIII rotating basket method with some slight modifications. Little release of FD-4 from the pellets was observed in phosphate buffered saline. However, the release of FD-4 was markedly increased in the presence of rat cecal contents. The intestinal absorption of insulin and (Asu(1,7))eel-calcitonin after oral administration of the azopolymer-coated pellets containing these peptides with camostat mesilate was evaluated by measuring the hypoglycemic and hypocalcemic effects, respectively. A slight decrease in plasma glucose levels was observed following the oral administration of these pellets containing 12.5 IU of insulin compared with the same dose of insulin solution. Camostat mesilate, a protease inhibitor that is incorporated with insulin in these pellets, further decreased the plasma glucose levels in a dose-dependent manner. Similar results were also obtained with the oral administration of pellets containing (Asu(1,7))eel-calcitonin. These findings suggest that azopolymer-coated pellets may be useful carriers for the colon-specific delivery of peptides including insulin and (Asu(1,7))eel-calcitonin.

Esophageal carcinoma with nonrecurrent inferior laryngeal nerve

Occurrence of a nonrecurrent inferior laryngeal nerve is quite rare. We present the case of a 70-year-old man with carcinoma of the esophagus. An abnormal right subclavian artery was detected preoperatively. This anomaly suggested that the right inferior laryngeal nerve branched directly from the vagal trunk. A carcinoma of the esophagus was resected, and lymph nodes were dissected. The right inferior laryngeal nerve was fully preserved, and the esophagus was primarily repaired.

Relapsed non-Hodgkin's lymphoma: detection and treatment

PURPOSE

To evaluate the optimal management strategy during clinical remission and after relapse in patients with non-Hodgkin's lymphoma (NHL).

METHODS

Sixty-six patients with relapse of NHL from a state of clinical remission between 1987 and 1997 were analyzed retrospectively. The pattern of relapses, diagnostic methods used for relapses, and clinical outcome of salvage treatment were analyzed with attention to time after the achievement of clinical remission.

RESULTS

Thirty-three relapses (50%) occurred within 12 months, and the remainder occurred gradually from 12-48 months after the first remission. Diagnosis of relapse in 61 of the 66 patients (93%) was made at unscheduled evaluations prompted by symptoms, on physical examinations, or because of high LDH levels. The 1- and 5-year cause-specific survival rates after relapse were 56.7% and 39.4%, respectively. The 1- and 5-year relapse-free survival rates were 50.1% and 35.0%, respectively. The 5-year relapse-free survival rate in patients with late relapse (49.5%) was significantly better than in those with early relapse (21.2%) (p<0.01).

CONCLUSION

Time to relapse may be a useful factor to determine optimal management strategy in NHL patients.

Up-regulation of genes encoding glycosylphosphatidylinositol (GPI)-attached proteins in response to cell wall damage caused by disruption of FKS1 in Saccharomyces cerevisiae

FKS1 and FKS2 encode alternative catalytic subunits of the glucan synthases that are responsible for synthesis of beta-1,3-glucan in the Saccharomyces cerevisiae cell wall. Disruption of FKS1 reduces the glucan content of the cell wall, increases chitin content and activates the expression of CWP1, which encodes a glycosylphosphatidylinositol (GPI)-dependent cell wall protein. These cellular responses have been regarded as compensating for cell wall damage in order to maintain cell wall integrity. Here, we report the identification, by genome-wide screening, of 22 genes that are transcriptionally up-regulated in fks1delta cells. Among them, five genes were found to encode GPI-attached proteins, three of which are covalently associated with the cell wall. Deletion and replacement analysis of the promoter regions identified Rlm1-binding sequences as being responsible for the up-regulation following disruption of FKS1. Using the rlm1delta tetOp-FKS1 strain, in which the expression of FKS1 can be repressed by doxycycline, we examined the requirement for Rlm1 for the transcriptional up-regulation of these five genes. Three of the five genes were not up-regulated by doxycycline, indicating that Rlm1 mediates their up-regulation when FKS1 is inactivated. The remaining two genes were up-regulated by doxycycline, suggesting that a transcription factor other than Rlm1 is involved in their response to disruption of FKS1.

Radiotherapy for localized relapse in patients with non-Hodgkin's lymphoma: a preliminary report

PURPOSE

To evaluate the usefulness of radiotherapy for relapse of non-Hodgkin's lymphoma (NHL) at a localized site.

METHODS

Of 79 patients with relapsed intermediate- or high-grade NHL, 13 patients (16.5%) with a localized relapse were analyzed retrospectively.

RESULTS

Five patients were treated with radiotherapy alone and eight were treated with radiotherapy plus conventional chemotherapy (CHOP or other combinations). Radiotherapy was delivered to the involved field to a mean total dose of 34.1 Gy (range, 21-51 Gy). The 5-year overall and disease-free survival rates were 80.2% and 76.2%, respectively. Four patients relapsed subsequently. After further salvage therapy, two patients died of NHL and two were alive without active disease.

CONCLUSION

Radiotherapy may be an important component of treatment for selected patients with NHL who relapse at a localized site.

[A case of primary intrapulmonary thymoma: its entity and the problem of lymph node dissection]

Primary intrapulmonary thymomas are defined as primary thymomas arising in an intrapulmonary location without an associated mediastinal component, and they are very rare. A total of 20 cases have been reported only sporadically in the English literature since 1951. We reported the case of 41-year-old woman who had a 3.5 x 3.0 x 3.0 cm lower right lobe mass with nodal metastasis that extended over the left atrium. We also summarized the clinicopathological features of a total of 21 cases and discussed the problems involved with diagnosis, pathogenesis and treatment. Knowledge of the biological behavior of primary intrapulmonary thymomas is limited because of their rarity. In particular, the issue of the need for lymph node dissection has not been adequately discussed. In this case, pathohistological examination revealed that the routes of lymphatic spread and the sites of noda metastases from primary intrapulmonary thymoma resemble those of primary lung cancer. Therefore, systematic mediastinal lymph node dissection according to the lymph node map for primary lung cancer should be recommended for malignant cases.

cDNA sequence of bovine thioredoxin

In this paper, we report the cDNA sequence of bovine thioredoxin. We determined the full-length cDNA sequence of bovine thioredoxin by RT-PCR, 5'-RACE and 3'-RACE methods. Currently, the thioredoxin cDNA sequences of only five mammalian species (human, macaca, mouse, ovine and rat) are registered in the GenBank database. We performed sequence comparisons on the total cDNA sequence and the coding region, and produced a multialignment between the amino acid sequences of bovine and other mammalian thioredoxins. The amino acid sequences of thioredoxins are highly conserved among mammalian species, for example, only one difference exists between the amino acid sequences of bovine and ovine thioredoxin.

cDNA sequence of bovine thioredoxin

In this paper, we report the cDNA sequence of bovine thioredoxin. We determined the full-length cDNA sequence of bovine thioredoxin by RT-PCR, 5'-RACE and 3'-RACE methods. Currently, the thioredoxin cDNA sequences of only five mammalian species (human, macaca, mouse, ovine and rat) are registered in the GenBank database. We performed sequence comparisons on the total cDNA sequence and the coding region, and produced a multialignment between the amino acid sequences of bovine and other mammalian thioredoxins. The amino acid sequences of thioredoxins are highly conserved among mammalian species, for example, only one difference exists between the amino acid sequences of bovine and ovine thioredoxin.

Amino acid residues in the omega-minus region participate in cellular localization of yeast glycosylphosphatidylinositol-attached proteins

The final destination of glycosylphosphatidylinositol (GPI)-attached proteins in Saccharomyces cerevisiae is the plasma membrane or the cell wall. Two kinds of signals have been proposed for their cellular localization: (i) the specific amino acid residues V, I, or L at the site 4 or 5 amino acids upstream of the GPI attachment site (the omega site) and Y or N at the site 2 amino acids upstream of the omega site for cell wall localization and (ii) dibasic residues in the region upstream of the omega site (the omega-minus region) for plasma membrane localization. The relationships between these amino acid residues and efficiencies of cell wall incorporation were examined by constructing fusion reporter proteins from open reading frames encoding putative GPI-attached proteins. The levels of incorporation were high in the constructs containing the specific amino acid residues and quite low in those containing two basic amino acid residues in the omega-minus region. With constructs that contained neither specific residues nor two basic residues, levels of incorporation were moderate. These correlations clearly suggest that GPI-attached proteins have two different signals which act positively or negatively in cell wall incorporation for their cellular localization.

Non-Hodgkin lymphoma and coexisting primary cancers: a retrospective clinical analysis of 10 patients

The simultaneous occurrence of non-Hodgkin lymphoma (NHL) and primary cancers is rare, and the treatment strategy for both malignancies is unclear. The authors analyzed the clinical records of 10 patients with NHL and coexisting primary cancers. All patients initially had symptoms of NHL, and all carcinomas were found at the initial workup of NHL by chance. The most common primary sites of coexisting cancers were the stomach (six patients) and the colon (two). Histologically, the majority of NHLs were intermediate grade, and all lesions were B-cell type. All primary cancers were adenocarcinoma. Initially, NHL was treated with radiotherapy or chemotherapy. Six primary cancers were resected surgically or endoscopically after the remission of NHL. The remaining four patients received no treatment for primary cancers because of advanced stages or early relapse of NHL. Three patients died of NHL, one died of cancer, and six were still alive, five without evidence of disease and one with disease. The authors conclude that early detection of a coexisting cancer and appropriate treatment after the remission of NHL may increase the possibility of a cure.

[Usefulness and problems of total hepatic vascular exclusion in liver surgery]

Total hepatic vascular exclusion (THVE) is an useful method enabling safe and sure hepatic resection in patients with liver tumors adjacent to the large hepatic veins or inferior vena cava (IVC), tumor thrombi, invasion of the IVC, etc. To avoid serious hypotension during THVE, test clamping of the IVC prior to the procedure is indispensable. Hemodynamics should be carefully maintained by blood transfusion and sufficient infusion of colloidal and electrolyte solutions during THVE. The veno-venous bypass method which shunts blood from the IVC and portal vein to the superior vena cava enables prolongation of the period of THVE and is useful to avoid postoperative renal dysfunction. In situ liver perfusion with cold solution during THVE is an additional modality by which the liver is protected from warm ischemic injury and the duration of THVE can be further prolonged. However, the maximum duration of THVE is still controversial, especially in patients with chronic liver damage. The most appropriate method for THVE should be carefully chosen in each case by considering the type of lesion, liver function, and the goal of the surgery.