Rapid-fractionation pre-operative chemoradiation for malignant periampullary neoplasms

The multimodality treatment of adenocarcinoma of the pancreatic head has been shown to improve survival compared with surgery alone. The delivery of chemotherapy and radiation therapy (chemoradiation) before rather than after pancreaticoduodenectomy ensures that all patients who undergo surgery receive the other components of multimodality therapy. In an effort to reduce overall treatment time and cost, the use of rapid-fractionation preoperative chemoradiation was explored. Radiation therapy was delivered with 18-MeV photons to a total dose of 30 Gy given in 10 fractions over 2 weeks. 5-Fluorouracil was given concurrently by continuous infusion at a dose of 300 mg m-2 day-1. Four weeks after the completion of chemoradiation, patients underwent pancreaticoduodenectomy and electron-beam intraoperative radiation therapy (10 Gy). All patients completed the treatment programme without delay. The rapid-fractionation programme was delivered at nearly half the cost of standard chemoradiation and histologic evidence of tumour cell injury was present in all resected specimens. There were no perioperative anastomotic complications, and median hospital stay was 20 days. Rapid-fractionation chemoradiation warrants further study in the neoadjuvant setting.

70-nm-bandwidth achromatic waveguide coupler

We report a general approach to the design of broadband waveguide couplers. A double-parallel grating assembly is used to cancel the first chromatic order, and a proper choice of prism glass and base angle is made to compensate for the second chromatic order. The technique was applied to a Corning glass 7059 waveguide, and a spectral bandwidth of 70 nm was measured by the use of two complementary procedures.

Significance of peritoneal cytology in patients with potentially resectable adenocarcinoma of the pancreatic head

BACKGROUND

Recurrence in the peritoneum occurs in up to 50% of patients after a potentially curative pancreaticoduodenectomy. Previous authors have implicated preoperative fine-needle aspiration (FNA) as a cause of intraperitoneal tumor dissemination, although prior studies of peritoneal cytology findings have largely involved patients with locally advanced disease.

METHODS

A consecutive series of patients referred to our institution between 1991 and 1993 with suspected or biopsy-proven adenocarcinoma of the pancreatic head was studied prospectively. All patients fulfilled criteria for resectability as assessed by computed tomography: no metastatic disease, no encasement of the superior mesenteric or hepatic arteries, and a patent superior mesenteric-portal venous confluence. Peritoneal washings were obtained at the time of staging laparoscopy and/or at subsequent laparotomy. Data regarding peritoneal cytology results, previous FNA, preoperative chemoradiation, eventual resection, pattern of disease recurrence, and survival were collected.

RESULTS

A total of 80 peritoneal washings from 60 consecutive patients were prospectively examined. Forty-nine (82%) of 60 patients underwent FNA before peritoneal washings were obtained. A total of four patients (7%) had positive peritoneal cytology findings: three (6%) of 49 who underwent prior FNA and one (9%) of 11 with no prior FNA. Similarly, no differences in eventual peritoneal failure or short-term survival were observed for patients who underwent prior FNA compared with patients who did not. All four patients with positive peritoneal cytology findings had metastatic disease (liver, three; peritoneum, one) at a median of 4.8 months after diagnosis; three of the four died of disease at a median of 8 months.

CONCLUSIONS

Positive peritoneal cytology findings are rare in patients with radiologically resectable adenocarcinoma of the pancreas. When found, positive peritoneal washings are an indicator of advanced disease characterized by unresectability, early metastasis, and short survival. Computed tomographic-guided FNA does not appear to increase the risk for positive peritoneal washings and represents a valid approach to the pretreatment diagnosis of patients with suspected pancreatic malignancy.

beta-Endorphin enhances the replication of neurotropic human immunodeficiency virus in fetal perivascular microglia

The effect of an endogenous opiate, beta-endorphin, on the replication of HIV was investigated in brain perivascular microglia. Beta-endorphin enhanced the synthesis of p-24 antigen and transactivation of HIV promoter. Dialysed culture supernatants of endorphin-treated microglia re-activated latent HIV infection. These culture supernatants showed elevated levels of interleukin-1 beta, IL-6 and tumor necrosis factor alpha. Sub-optimal concentration of beta-endorphin potentiated GP-120-induced synthesis of these cytokines. Nalaxone reversed beta-endorphin-induced, but not GP-120-induced, cytokine production and enhanced HIV replication. These results suggest that endogenous opiates may contribute to the progression of AIDS dementia complex.

Conversion of Xenopus ectoderm into neurons by NeuroD, a basic helix-loop-helix protein

Basic helix-loop-helix (bHLH) proteins are instrumental in determining cell type during development. A bHLH protein, termed NeuroD, for neurogenic differentiation, has now been identified as a differentiation factor for neurogenesis because (i) it is expressed transiently in a subset of neurons in the central and peripheral nervous systems at the time of their terminal differentiation into mature neurons and (ii) ectopic expression of neuroD in Xenopus embryos causes premature differentiation of neuronal precursors. Furthermore, neuroD can convert presumptive epidermal cells into neurons and also act as a neuronal determination gene. However, unlike another previously identified proneural gene (XASH-3), neuroD seems competent to bypass the normal inhibitory influences that usually prevent neurogenesis in ventral and lateral ectoderm and is capable of converting most of the embryonic ectoderm into neurons. The data suggest that neuroD may participate in the terminal differentiation step during vertebrate neuronal development.

HLA-DQB1*0301 association with increased cutaneous melanoma risk

Susceptibility to a variety of malignancies has been linked to human leukocyte antigen (HLA) genes, including the HLA class II allele DQB1*0301. To determine whether melanoma risk is associated with HLA class II alleles, molecular oligotyping of HLA class II-DRB1, -DQA1 and -DQB1 genes was performed for 45 patients with melanoma. The DQB1*0301 allele was present in 56% of melanoma patients vs. 27% of 200 local Caucasian controls. This difference was highly significant (Bonferroni's-corrected chi-square p = 0.003, OR = 3.4). No other class II allele tested was present at significantly increased or decreased frequency in melanoma patients. Furthermore, presence of DQB1*0301 in melanoma patients was associated with advanced disease. Melanoma patients carrying the DQB1*0301 allele presented on average with thicker primary tumors (mean 3.7 mm vs. 1.8 mm, 2-tailed p = 0.02) and were more likely to present with regional or distant metastatic disease (stages III-IV, 44% vs. 5%, chi-square p = 0.003), compared to melanoma patients without DQB1*0301. Risk of melanoma incidence or progression may be influenced by DQB1*0301 or a closely linked gene.

A novel strong promoter of the groEx operon of symbiotic bacteria in Amoeba proteus

Gram- symbiotic bacteria (called X-bacteria), present in the xD strain of Amoeba proteus as required cell components, contain a large amount of a 67-kDa protein, a GroEL analog. The complete nucleotide (nt) sequence of the groEx operon of X-bacteria has been determined and it has a high degree of nt identity with those of other bacterial groE operons. The groELx gene is expressed in transformed Escherichia coli and has a novel and potent promoter (P2) in addition to the heat-shock consensus promoter (P1). This is shown by the production of GroELx in Escherichia coli transformed with modified DNA clones lacking P1 and by an enhanced production of a GroELx::beta-galactosidase fusion protein when a portion of groEx containing P2 is linked to the lacZ gene. Primer-extension analyses revealed the presence of possible P2 sequences within the open reading frame of the groESx gene. It is suggested that the presence of a potent P2 in the X-bacterial gene is an adaptation for the endosymbiotic bacteria to survive within a potentially hostile intracellular environment.

Managing unsuspected tumor invasion of the superior mesenteric-portal venous confluence during pancreaticoduodenectomy

Most surgeons believe that tumor invasion of the superior mesenteric-portal venous (SMPV) confluence is a contraindication to pancreaticoduodenectomy for adenocarcinoma of the pancreas or periampullary region. Traditional techniques for performing pancreaticoduodenectomy have emphasized the importance of establishing a tumor-free plane between the SMPV confluence and the neck of the pancreas. However, this maneuver does not reveal tumor invasion of the lateral wall of the superior mesenteric vein (SMV) until after gastric and pancreatic transection--a point at which the surgeon has committed to resection. This unexpected but not uncommon finding likely contributes to the high incidence of margin-positive resections and subsequent local tumor recurrence. We describe our technique for segmental resection of the SMPV confluence at the time of pancreaticoduodenectomy. Routine ligation of the splenic vein and primary anastomosis of the SMV and portal vein have been abandoned in favor of an interposition graft using internal jugular vein.

A comparative study of the efficacy of postoperative analgesia with intraoperative epidural lidocaine with or without morphine

We compared postoperative analgesia in 15 patients (group A) who were given intraoperative epidural morphine 3 mg and lidocaine 150 mg after laminectomy/discectomy with that of 15 patients (group B) who were given only epidural lidocaine 150 mg. Epidural administration was accomplished by direct placement of the epidural catheter into the epidural space under direct vision during surgery. Eight patients (53%) in group A and 15 patients (100%) in group B required supplementary narcotics during the first 24 h postoperatively (P<0.05). The amount of supplementary narcotics given to group A patients was significantly less than that for group B (P<0.05), and the pain scores for group A patients were also significantly lower at 1, 2, and 6 h postoperatively (P<0.05). There was no difference in the observed side effects in the two groups. We conclude that postoperative pain relief following laminectomy/discectomy is superior when epidural morphine is added to lidocaine than when lidocaine is being used alone.

The Haw River syndrome: dentatorubropallidoluysian atrophy (DRPLA) in an African-American family

Haw River Syndrome (HRS) is a dominant neurodegenerative disease that has affected five generations of an African-American family in rural North Carolina. The disorder represents a unique spectrum of multiple system degenerations resembling Huntington's disease, spinocerebellar atrophy and dentatorubropallidoluysian atrophy (DRPLA), a neurodegenerative disease that has been primarily reported in Japan. Recently, DRPLA has been shown to be due to an expanded trinucleotide repeat located on chromosome 12pter-p12. We have genotyped this family and found HRS to be tightly linked to the DRPLA region. Further examination demonstrates that, despite their distinct cultural origins and clinical and pathological differences, HRS is caused by the same expanded CTG-B37 repeat as DRPLA.

Role of polyamines on de novo shoot morphogenesis from cotyledons of Brassica campestris ssp. pekinensis (Lour) Olsson in vitro

The promotive effect of ethylene inhibitors (Els), i.e. AgNO3 and aminoethoxyvinylglycine (AVG) on de novo shoot regeneration from cultured cotyledonary explants of Brassica campestris ssp. pekinensis cv. Shantung in relation to polyamines (PAs) was investigated. The endogenous levels of free putrescine and spermidine in the explant decreased sharply after 1-3 days of culture, whereas endogenous spermine increased, irrespective of the absence or presence of Els. AgNO3 at 30 μM did not affect endogenous PAs during two weeks of culture. In contrast, explants grown on medium containing 5 μM AVG produced higher levels of free putrescine and spermine which increased rapidly after three days and reached a peak at 10 days. An exogenous application of 5 mM putrescine also resulted in a similar surge of endogenous free spermine of the explant. More strikingly, shoot regeneration from explants grown in the presence of 1-20 mM putrescine, 0.1-2.5 mM spermidine, or 0.1-1 mM spermine was enhanced after three weeks of culture. However, exogenous PAs generally did not affect ethylene production, and endogenous levels of 1-aminocyclopropane-1-carboxylate (ACC) synthase activity and ACC of the explant. This study shows the PA requirement for shoot regeneration from cotyledons of B. campestris ssp. pekinensis in vitro, and also indicates that the promotive effect of PAs on regeneration may not be due to an inhibition of ethylene biosynthesis.

Allosteric interaction of a herpes simplex viral thymidine kinase with host DNA polymerase alpha in mouse LP1-1 cells

A DNA polymerase alpha-associated multienzyme complex isolated from mouse LP1-1 cells transfected with the thymidine kinase gene of herpes simplex virus type I (1) showed activities of DNA polymerase alpha, topoisomerase II, and thymidine kinase (TK) in the complex. TK antiserum recognized a 43 kDa polypeptide only in the fraction of the multienzyme complex prepared from the LP1-1 cells but not that from L-M(TK-) cells. In permeabilized cells, hydroxyurea did not show any inhibitory effect on either DNA polymerase or TK, whereas aphidicolin, novobiocin, and TK antiserum inhibited both enzymes. These results provide evidence for the functional association and an allosteric interaction between the viral TK and host DNA polymerase alpha.

Adrenal medullary disease in multiple endocrine neoplasia type 2. Appropriate management

This article discusses screening for pheochromocytoma and timing of surgery, unilateral versus bilateral adrenalectomy. Anterior, posterior, and laparoscopic operative techniques are reviewed also.

The complete sequence and promoter activity of the human A-raf-1 gene (ARAF1)

The raf proto-oncogenes encode cytoplasmic protein serine/threonine kinases, which play a critical role in cell growth and development. One of these, A-raf-1 (human gene symbol, ARAF1), which is predominantly expressed in mouse urogenital tissues, has been mapped to an evolutionarily conserved linkage group composed of ARAF1, SYN1, TIMP, and properdin located at human chromosome Xp11.2. We have isolated human genomic DNA clones containing the expressed gene (ARAF1) on the X chromosome and a pseudogene (ARAF2) on chromosome 7p12-q11.21. Analysis of the nucleotide sequence from the ARAF1 genomic clones demonstrated that it consists of 16 exons encoded by minimally 10,776 nucleotides. The major transcriptional start site (+1) was determined by RNase protection and primer extension assays. Promoter activity was confirmed by functional assays using DNA fragments fused to a CAT reporter gene. The ARAF1 minimal promoter, located between nucleotides -59 and +93, has a low G + C content and lacks consensus TATA and Inr sequences but shows sequence similarity at position -1 to the E box that is known to interact with USF and TFII-I transcription factors.

Nonfunctioning islet cell carcinoma of the pancreas

BACKGROUND

Nonfunctioning islet cell carcinoma of the pancreas has a variable and often indolent natural history, which has resulted in a wide range of treatment recommendations. To more clearly define the natural history and appropriate treatment of this disease, we reviewed our institutional experience over the last 39 years.

METHODS

The records of all patients confirmed to have a nonfunctioning islet cell carcinoma of the pancreas were retrospectively reviewed. Kaplan-Meier life tables were constructed and log-rank comparisons were performed.

RESULTS

The 73 patients studied had an overall 5-year actuarial survival rate of 50%. Patients with localized disease at presentation (n = 39) had a significantly higher survival rate (p = 0.03) compared with patients with metastatic disease (n = 34). The 19 patients who underwent a potentially curative resection of the primary tumor had a significantly higher survival rate (p = 0.03) compared with the 20 patients with locally advanced, unresectable, nonmetastatic disease. Nine of these 20 patients died of complications of the primary tumor. In contrast, only 2 of 22 cancer-related deaths in the 34 patients with metastatic disease at diagnosis were due to the primary tumor.

CONCLUSIONS

(1) Surgical resection should be performed in patients with resectable nonmetastatic disease. (2) Resection of the primary tumor in the presence of metastatic disease is rarely indicated. (3) Innovative treatment strategies are needed for patients with locally advanced, unresectable, nonmetastatic tumors of the pancreatic head.

Parental imprinting of an Igf-2 transgene

As a consequence of parental imprinting in mice, the paternal allele encoding insulin-like growth factor-II (IGF-II) is expressed, whereas the maternal allele is silent in most tissues. To examine whether cis-acting sequences involved in imprinting are located in the vicinity of the Igf-2 gene, we have constructed mouse transgenic lines and studied the expression of a 30 kb rat Igf-2 transgene, in which the coding region has been replaced with the lacZ reporter sequence. Chromatin position effects and/or absence of long-range regulatory elements seem to have affected tissue-specific expression in the transgenic mice. However, in one of six expressing lines, staining of embryos for beta-galactosidase activity was detected in a minor subset of tissues normally transcribing the endogenous homolog, but only when the transgene was transmitted paternally. This transgene was integrated into mouse chromosome 19, which is apparently free of imprinted loci. Although the possibility that the Igf-2 transgene was inserted into an as yet unidentified imprinted locus is discussed, a more likely interpretation of our results is that the transgene carries at least a portion of its own imprinting signal, because it consists of the genomic sequences of a locus already known to be imprinted and maintains the correct imprinting mode.

Purification and characterization of bovine brain gamma-aminobutyraldehyde dehydrogenase

gamma-Aminobutyraldehyde dehydrogenase was purified to homogeneity from bovine brain. The molecular weight of the native enzyme and subunit were 230,000 and 58,000, respectively. The Km value for gamma-aminobutyraldehyde and NAD+ were 154 microM and 53 microM, respectively. The optimum pH and temperature were 8.0 and 37 degrees C, respectively. N-terminal sequence of the enzyme is as follows: NH2-S-A-A-T-Q-A-V-P-T-P-N-Q-Q-COOH. The enzyme migrates on isoelectric focusing with pI = 6.5. Enhancement of the enzyme activity by polyamine, Mn2+, Mg2+ and inhibition by gamma-aminobutyric acid and Zn2+ will enhance the limited information on regulation of the gamma-ABALDH activity and GABA metabolism to some extent.

Human cytotoxic T-lymphocytes specific for autologous follicular lymphoma recognize immunoglobulin in a major histocompatibility complex restricted fashion

BACKGROUND

Previously, autologous Burkitt lymphoma-specific cytotoxic T-lymphocytes (CTL) were found to express the gamma and delta T-cell receptor and recognize tumor idiotype in a major histocompatibility complex (MHC) unrestricted fashion.

METHODS

In this study, the authors established autologous CTL lines and clones specific for a B-cell follicular lymphoma.

RESULTS

These CTL are tumor specific and inhibited by antiimmunoglobulin monoclonal antibodies, but unlike the Burkitt lymphoma-specific CTL, they are MHC restricted and express the alpha and beta T-cell receptor.

CONCLUSIONS

These studies suggest that different B-cell lymphomas can induce CTL of different phenotypes and MHC restriction.

The identification and characterization of KRAB-domain-containing zinc finger proteins

The zinc finger motif is a highly conserved tandemly repeated sequence of 28-30 amino acids that was first identified in transcription factor TFIIIA from Xenopus laevis. Subsequently, similar motifs were found and characterized in many genes from mammalian genomes and the genomes of lower eukaryotes such as Drosophila and yeast, thereby defining a large superfamily of genes. Non-finger-coding modules conserved among members of subfamilies of zinc finger genes have been described in the murine genome (finger-associated boxes, or FAX domain) and the human genome (Krüppel-associated boxes, or KRAB domain). Here we report the identification and partial characterization of more members of the human KRAB-containing subfamily of genes. Based on Southern blot hybridization experiments, they also are zinc-finger-coding genes. All members share a highly homologous 42-amino-acid-long A element of the described KRAB domain. The conservation extends to the murine developmentally expressed zinc finger gene, mKr2. The homologous sequences, however, are part of the 5'-untranslated region. In all cases for which there is adequate information, the KRAB domain is found at the NH2-terminus of the respective protein. In one zinc-finger-encoding cDNA clone that we characterized further in this work, BRc1744 (ZNF45), the KRAB domain most probably constitutes the entire second exon of the gene. Based on the data, it is tempting to speculate that the FAX- and KRAB-containing zinc finger genes define subfamilies of genes with overlapping functions that participate in the regulation of common or similar developmental programs.

Interleukin 3 is a growth factor for human follicular B cell lymphoma

More than one-half of adults with non-Hodgkin's B cell lymphomas present with low-grade follicular lymphomas. These tumor cells are found in close association with follicular T lymphocytes and dendritic cells, suggesting that the surrounding cells may play a role in the support of follicular tumors. Supernatants from activated human peripheral blood lymphocytes were found to promote the in vitro proliferation of follicular tumor cells. This effect was entirely due to interleukin 3 (IL-3), a factor generally thought to cause the growth and differentiation of immature hematopoietic cells. IL-3 receptors were detected on fresh isolates of all primary follicular cell tumors examined. These findings suggest that follicular cell tumors may be dependent in vivo on IL-3 and that therapies directed against IL-3, its receptor, or the T cells that produce it may be effective treatment for follicular lymphoma.

Isolation and localization of a slow troponin (TnT) gene on chromosome 19 by subtraction hybridization of a cDNA muscle library using myotonic dystrophy muscle cDNA

Subtraction hybridization techniques were used to isolate 91 cDNA clones which are overexpressed in normal control skeletal muscle relative to muscle from patients with myotonic muscular dystrophy. The gene responsible for myotonic dystrophy (DM) has been localized to the 19q13.2-13.3 region of chromosome 19. To test as a candidate gene for DM, clones which represent differences in transcription are analyzed for localization to chromosome 19. One clone, designated MSL 366, was found to be on the long arm of chromosome 19 distal to the CKMM gene at 19q13.2. Sequence analysis confirmed that MSL 366 is the cDNA for human slow skeletal muscle troponin T. A genomic clone has been isolated and linkage studies with DM are in progress.