Local ordering in the pseudogap state of the high-Tc superconductor Bi2Sr2CaCu2O(8+delta)

We report atomic-scale characterization of the pseudogap state in a high-Tc superconductor, Bi2Sr2CaCu2O(8+delta). The electronic states at low energies within the pseudogap exhibit spatial modulations having an energy-independent incommensurate periodicity. These patterns, which are oriented along the copper-oxygen bond directions, appear to be a consequence of an electronic ordering phenomenon, the observation of which correlates with the pseudogap in the density of electronic states. Our results provide a stringent test for various ordering scenarios in the cuprates, which have been central in the debate on the nature of the pseudogap and the complex electronic phase diagram of these compounds.

Structural basis of presequence recognition by the mitochondrial protein import receptor Tom20

Most mitochondrial proteins are synthesized in the cytosol as precursor proteins with a cleavable N-terminal presequence and are imported into mitochondria. We report here the NMR structure of a general import receptor, rat Tom20, in a complex with a presequence peptide derived from rat aldehyde dehydrogenase. The cytosolic domain of Tom20 forms an all alpha-helical structure with a groove to accommodate the presequence peptide. The bound presequence forms an amphiphilic helical structure with hydrophobic leucines aligned on one side to interact with a hydrophobic patch in the Tom20 groove. Although the positive charges of the presequence are essential for import ability, presequence binding to Tom20 is mediated mainly by hydrophobic rather than ionic interactions.

Genetic variants of IL-13 signalling and human asthma and atopy

Asthma and atopy show epidemiological association and are biologically linked by T-helper type 2 (T(h)2) cytokine-driven inflammatory mechanisms. IL-4 operates through the IL-4 receptor (IL-4R, a heterodimer of IL-4Ralpha and either gammac or IL-13Ralpha1) and IL-13 operates through IL-13R (a heterodimer of IL-4Ralpha and IL-13Ralpha1) to promote IgE synthesis and IgE-based mucosal inflammation which typify atopy. Recent animal model data suggest that IL-13 is a central cytokine in promoting asthma, through the stimulation of bronchial epithelial mucus secretion and smooth muscle hyper-reactivity. We investigated the role of common genetic variants of IL-13 and IL-13Ralpha1 in human asthma, considering IgE levels. A novel variant of human IL-13, Gln110Arg, on chromosome 5q31, associated with asthma rather than IgE levels in case-control populations from Britain and Japan [peak odds ratio (OR) = 2.31, 95% CI 1.33-4.00]; the variant also predicted asthma and higher serum IL-13 levels in a general, Japanese paediatric population. Immunohistochemistry demonstrated that both subunits of IL-13R are prominently expressed in bronchial epithelium and smooth muscle from asthmatic subjects. Detailed molecular modelling analyses indicate that residue 110 of IL-13, the site of the charge-modifying variants Arg and Gln, is important in the internal constitution of the ligand and crucial in ligand-receptor interaction. A non-coding variant of IL-13Ralpha1, A1398G, on chromosome Xq13, associated primarily with high IgE levels (OR = 3. 38 in males, 1.10 in females) rather than asthma. Thus, certain variants of IL-13 signalling are likely to be important promoters of human asthma; detailed functional analysis of their actions is needed.

Cable properties of smooth muscle

1. The cable properties of smooth muscle of guinea-pig taenia coli were studied by intracellular recording of electrotonic potentials produced by square current pulses and alternating current applied with external electrodes.2. An electrical model of the smooth muscle was constructed to test how the junctional resistance between cells affected the cable properties. The model consisted of a series of short cables (representing cells) which were connected by junctional resistances.3. It was concluded, from the experiments on the living tissue and on the model, that the electrotonic potential in smooth muscle can be expressed by the ordinary cable equation used for nerve and skeletal muscle fibres, even though the junctional resistance is of the same order of magnitude as that of the myoplasmic resistance.4. The cable equation was used to analyse the membrane parameters from the electrotonic potential, from the time course of the foot of the spike and from the conduction velocity. The analysis indicates that the smooth muscle has a membrane capacity of 2-3 muF/cm(2) and a membrane resistance of 30-50 kOmega cm(2).

Curcumin inhibition of inflammatory cytokine production by human peripheral blood monocytes and alveolar macrophages

Curcumin, a dietary pigment responsible for the yellow colour of curry, has been used for the treatment of inflammatory diseases and exhibits a variety of pharmacological effects such as anti-inflammatory activity. The mechanism in anti-inflammatory activity of curcumin has been investigated; however, little is known about the effect of curcumin on cytokine production by human peripheral blood monocytes and alveolar macrophages. In the present study, we shed light on the effect of curcumin on inflammatory cytokine production by human peripheral blood monocytes and alveolar macrophages. To this end, we determined the concentrations of interleukin-8 (IL-8), monocyte inflammatory protein-1 (MIP-1alpha), monocyte chemotactic protein-1 (MCP-1), interleukin-1beta (IL-1beta), and tumour necrosis factor-alpha (TNF-alpha) in the culture supernatants from phorbor ester, 4beta phorbor 12beta-myristate-13alpha acetate (PMA)- or lipo-polysaccharide (LPS)-stimulated monocytes and alveolar macrophages in the presence or absence of curcumin. Curcumin inhibited the production of IL-8, MIP-1alpha, MCP-1, IL-1beta, and TNF-alpha by PMA- or LPS-stimulated monocytes and alveolar macrophages in a concentration- and a time-dependent manner. These results show that curcumin exhibits an inhibitory effect on the production of IL-8, MIP-1alpha, MCP-1, IL-1beta, and TNF-alpha by PMA- or LPS-stimulated monocytes and alveolar macrophages.

Intermolecular interaction effects in the amide I vibrations of polypeptides

Previous perturbation treatments of the Amide I vibrations of beta polypeptides are inconsistent with a detailed normal coordinate analysis of crystalline polyglycine I. This analysis indicates that the D(10) interaction constant is essentially zero, rather than the large value (about 20 cm(-1)) required by the earlier application of the perturbation theory. It is suggested that the previously neglected D(11) term should be included in the perturbation expression, and it is shown that the physical origin of such a term can be accounted for by transition dipole coupling. This mechanism is shown to give a reasonable explanation of splittings of the C=O stretching vibrations in hydrogenbonded carboxylic acid dimers. Its application to beta polypeptides provides a satisfactory interpretation of splittings in the Amide I modes.

Somatosensory homunculus as drawn by MEG

We studied a detailed somatosensory representation map of the human primary somatosensory cortex using magnetoencephalography. Somatosensory-evoked magnetic fields following tactile stimulation of multiple points in the right hemibody (including the tongue, lips, fingers, arm, trunk, leg, and foot) were analyzed in five normal subjects. We were able to estimate equivalent current dipoles (ECDs) following stimulation of the tongue, lips, fingers, palm, forearm, elbow, upper arm, and toes in most subjects and those following the stimulation of the chest, ankle, and thigh in one subject. The ECDs were located in the postcentral gyrus and generally arranged in order along the central sulcus, which is compatible with the somatosensory "homunculus." Linear distances, averaged in five subjects, from the receptive area of the thumb to that of the tongue, little finger, forearm, upper arm, and toes were estimated to be 2.42 +/- 0.28, 1.25 +/- 0.28, 2.21 +/- 0.72, 2.75 +/- 0.63, and 5.29 +/- 0.48 cm, respectively. The moment of each ECD, which suggested the size of the cortical areas responsive to the stimulation, was also compatible with the bizarre proportion of the homunculus with a large tongue, lips, and fingers. According to these results, we were able to reproduce a large part of the somatosensory homunculus quantitatively on an individual brain MRI.

Vascular endothelial growth factor (VEGF) mRNA isoform expression pattern is correlated with liver metastasis and poor prognosis in colon cancer

Vascular endothelial growth factor (VEGF) is a well known factor that induces angiogenesis. Four isoforms, i.e. VEGF206, 189, 165, and 121, have been identified. We examined the isoform patterns of VEGF mRNA using reverse transcription polymerase chain reaction (RT-PCR) analysis in 61 colon cancers. All the colon cancers examined expressed VEGF121. The isoform patterns were classified into three groups: type 1, VEGF121; type 2, VEGF121 + VEGF165; type 3, VEGF121 + VEGF165 + VEGF189. Three of the 61 colon cancers examined showed type 1 expression, 26 showed type 2 expression and 32 showed the type 3 pattern. The patients with liver metastases showed the type 3 isoform expression pattern at a significantly higher incidence (12 of 16, 75%) than those without liver metastasis (20 of 45, 44%) (P=0.036). The type 3 isoform pattern was significantly associated with M1 stage (P=0.019). The patients with colon cancer and the type 3 isoform pattern showed significantly poor prognosis (P < 0.01, Cox-Mantel). The colon cancers with the type 3 pattern showed a significantly higher involvement of veins (P=0.006). These observations suggest that the aberrant type 3 expression pattern of VEGF189 mRNA isoforms is correlated with liver metastasis, M stage, and poor prognosis in colon cancer.

Preparation and mechanical properties of polylactic acid composites containing hydroxyapatite fibers

Ceramic-polymer composite biomaterials were prepared by hot-pressing a mixture consisting of poly-L-lactic acid (PLA) and hydroxyapatite fibers (HAF) with dimensions of 40-150 microm length and 2-10 microm diameter, which were converted from beta-Ca(PO3)2 fibers. After PLA dissolved with methylene chloride was mixed with the fibers, the mixture was dried completely and subsequently hot-pressed uniaxially under a pressure of 40 MPa at 180 degrees C, resulting in the fabrication of the PLA/HAF composite. The modulus of elasticity was improved effectively even by introducing a small amount of HAF; almost no degradation in the bending strength was observed and the modulus of elasticity showed high values of 5-10 GPa when the fibers of 20-60 wt% were introduced. With increasing HAF content, the maximum strain decreases and the specimen is apt to show a brittle fracture; this result implies that HAF in the composites can share the applied load efficiently due to the formation of a bond between HAF and PLA.

Crystal structure of a multifunctional 2-Cys peroxiredoxin heme-binding protein 23 kDa/proliferation-associated gene product

Heme-binding protein 23 kDa (HBP23), a rat isoform of human proliferation-associated gene product (PAG), is a member of the peroxiredoxin family of peroxidases, having two conserved cysteine residues. Recent biochemical studies have shown that HBP23/PAG is an oxidative stress-induced and proliferation-coupled multifunctional protein that exhibits specific bindings to c-Abl protein tyrosine kinase and heme, as well as a peroxidase activity. A 2.6-A resolution crystal structure of rat HBP23 in oxidized form revealed an unusual dimer structure in which the active residue Cys-52 forms a disulfide bond with conserved Cys-173 from another subunit by C-terminal tail swapping. The active site is largely hydrophobic with partially exposed Cys-173, suggesting a reduction mechanism of oxidized HBP23 by thioredoxin. Thus, the unusual cysteine disulfide bond is involved in peroxidation catalysis by using thioredoxin as the source of reducing equivalents. The structure also provides a clue to possible interaction surfaces for c-Abl and heme. Several significant structural differences have been found from a 1-Cys peroxiredoxin, ORF6, which lacks the C-terminal conserved cysteine corresponding to Cys-173 of HBP23.

Stoichiometric water splitting into H2 and O2 using a mixture of two different photocatalysts and an IO3-/I- shuttle redox mediator under visible light irradiation

The stoichiometric splitting of water into H2 and O2 (H2/O2 = 2) under visible light irradiation (lambda > 420 nm) took place for the first time using a mixture of Pt-WO3 and Pt-SrTiO3 (Cr-Ta-doped) photocatalysts and an IO3-/I- shuttle redox mediator.

Levels of soluble cell adhesion molecules in patients with dyslipidemia

BACKGROUND

Increased expression of cell adhesion molecules (CAMs) on the vascular endothelium has been postulated to play an important role in atherogenesis. Both in vitro and in vivo studies have suggested that dyslipidemia may increase expression of CAMs.

METHODS AND RESULTS

To determine whether dyslipidemia is associated with increased expression of CAMs, we examined the levels of soluble intercellular adhesion molecule 1 (sICAM-1), soluble vascular cell adhesion molecule 1 (sVCAM-1), and soluble E-selectin (sE-selectin) in individuals with either hypercholesterolemia or hypertriglyceridemia and in control subjects matched for age and sex. Patients with hypertriglyceridemia had significantly higher levels of sVCAM-1 (739 +/- 69 ng/mL) compared with patients with hypercholesterolemia (552 +/- 63 ng/mL) and control subjects (480 +/- 56 ng/mL). Levels of sICAM-1 were significantly increased in both the hypercholesterolemic and hypertriglyceridemic groups (298 +/- 29 and 342 +/- 31 ng/mL, respectively) compared with the control group (198 +/- 14 ng/mL). Levels of sE-selectin were significantly increased in hypercholesterolemic patients (74 +/- 9 ng/mL) compared with control subjects (48 +/- 5 ng/mL). Ten hypercholesterolemic patients were treated aggressively with atorvastatin alone or a combination of colestipol and either atorvastatin or simvastatin for a mean of 42 weeks and had an average LDL cholesterol reduction of 51%. Comparison of soluble CAMs before and after treatment showed a significant reduction only in sE-selectin (77 +/- 11 versus 56 +/- 6 ng/mL, P < or = .03) but not for sVCAM-1 or sICAM-1.

CONCLUSIONS

Although severe hyperlipidemia is associated with increased levels of soluble CAMs, aggressive lipid-lowering treatment had only limited effects on the levels. Increased levels of soluble CAMs in patients with hyperlipidemia may be a marker for atherosclerosis.

Adhesion to and decalcification of hydroxyapatite by carboxylic acids

Fundamental to the processes of decalcification of or adhesion to mineralized tissues is the molecular interaction of acids with hydroxyapatite. This study was undertaken to chemically analyze the interaction of 1 mono-, 2 di-, 1 tri-, and 2 polycarboxylic acids with hydroxyapatite in an attempt to elucidate the underlying mechanism. Maleic, citric, and lactic acid decalcified hydroxyapatite, in contrast to oxalic acid and the two polycarboxylic acids that were chemically bonded to hydroxyapatite. Solubility tests showed that the calcium salts of the former were very soluble, whereas those of the latter could hardly be dissolved in the respective acid solutions. Based on these data, an adhesion/decalcification concept was advanced that predicts that carboxylic acids, regardless of concentration/pH, either adhere to or decalcify hydroxyapatite, depending on the dissolution rate of the respective calcium salts in the acid solution. This contrasting behavior of organic acids most likely results from their differential structural conformations.

Cloning and expression of a novel MAPKK-like protein kinase, lymphokine-activated killer T-cell-originated protein kinase, specifically expressed in the testis and activated lymphoid cells

A novel protein kinase, TOPK (T-LAK cell-originated protein kinase), was isolated from a lymphokine-activated killer T (T-LAK) cell subtraction cDNA fragment library. The open reading frame of the TOPK gene encodes a protein of 322 amino acids, possessing a protein kinase domain profile. The cap site analysis of the 5'-end of TOPK mRNA revealed two forms, a major full-length form and a minor spliced form at the 5'-site, both encoding the same protein. A BLAST homology search and phylogenetic analysis indicated that TOPK is related to dual specific mitogen-activated protein kinase kinase (MAPKK). The transfection of the TOPK gene to COS-7 cells up-regulated a phosphorylation of p38 MAPK but not ERK1/2 or SAPK/JNK. Gel precipitation study indicated that TOPK protein can be associated with p38 in vitro. Tissue distribution of TOPK mRNA expression was specific for the testis, T-LAK cells, activated lymphoid cells, and lymphoid tumors. On the other hand, deactivated T-LAK cells did not show TOPK mRNA expression. These data suggest that TOPK is a newly identified member of a novel MEK3/6-related MAPKK that may be enrolled in the activation of lymphoid cells and support testicular functions.

MR imaging of the fetus by a HASTE sequence

OBJECTIVE

The value of a half-Fourier acquisition single-shot turbo spin-echo (HASTE) sequence, in which high-resolution heavily T2-weighted images can be obtained within 2 sec, was evaluated in the imaging of the fetus during the second or third trimester.

MATERIALS AND METHODS

Eighteen women with complicated pregnancies as revealed on a sonogram during the second and third trimesters (16-36 weeks' gestation) were studied with a 1.5-T superconductive MR imaging unit that used a body phased-array coil. After informed consent, T1-weighted fast low-angle shot images, T2-weighted turbo spin-echo images, and HASTE images were obtained without any premedication. Images were analyzed with regard to image quality, degree of blurring, visualization of the normal fetal organs, and visualization of fetal and maternal abnormalities.

RESULTS

On HASTE sequences, visualization of the fetal brain, visceral organs (lung, heart, liver, kidney, and bladder), extremities, and umbilical cord were significantly better than on fast low-angle shot or turbo spin-echo sequences (p < .01). In the brain, the white matter-gray matter distinction, gyrus formation, and myelination of the brain were clearly revealed by the HASTE sequence. Pathologic processes including fetal abnormalities (anomalies of the central nervous systems [n = 5], placenta previa [n = 1], and transverse lie in the third trimester [n = 1]) and maternal abnormalities (leiomyoma [n = 5], ovarian tumors [n = 3], and hydronephrosis [n = 1]) were clearly seen on HASTE imaging. The peak specific absorption rate for RF exposure in these studies was less than 1.5 W/kg.

CONCLUSION

In situations when sonography is suggestive but not definitive, MR imaging with a HASTE sequence allows clear fetal imaging with high T2-weighted contrast.

Helicobacter pylori infection prevents erosive reflux oesophagitis by decreasing gastric acid secretion

BACKGROUND

Helicobacter pylori infection is less prevalent and atrophic gastritis is less extensive in patients with reflux oesophagitis than those without it, but few studies have examined this relationship directly.

AIMS

We investigated the relationship between H pylori infection, acid secretion, and reflux oesophagitis in Japanese subjects.

SUBJECTS

A total of 105 patients with erosive reflux oesophagitis were compared with 105 sex and age matched patients without reflux oesophagitis.

METHODS

The diagnosis of H pylori infection was made by histological examination of gastric mucosal biopsy specimens, rapid urease test, and detection of serum IgG antibodies. Acid secretion was assessed by the endoscopic gastrin test.

RESULTS

H pylori infection was present in 36 patients with erosive reflux oesophagitis (34.3%) and in 80 control subjects (76.2%) (odds ratio 0.163, 95% confidence interval 0.09-0.29). Overall acid secretion was significantly greater in patients with reflux oesophagitis. Among H pylori positive patients, acid secretion was greater in patients with reflux oesophagitis than those without oesophagitis.

CONCLUSION

In Japan, erosive reflux oesophagitis occurs most often in the absence of H pylori infection and gastric hyposecretion. Even in the presence of H pylori infection, reflux oesophagitis is more likely to develop in patients without gastric hyposecretion. H pylori infection may inhibit reflux oesophagitis by inducing hypoacidity.

Zooarchaeological and taphonomic analysis of the Die Kelders Cave 1 layers 10 and 11 Middle Stone Age larger mammal fauna

Middle Stone Age (MSA) and Middle Paleolithic (MP) faunal assemblages have gained widespread attention due to their relevance to the debate over the modernity of hominid behavior during the MSA/MP. A recent critique of the scavenging argument for MSA/MP behavior drew on a summary presentation of the skeletal abundance and surface modification data from Die Kelders Cave 1 Layer 10 (Marean, 1998). This paper provides a more complete presentation of those data, adds the smaller Layer 11 sample, and provides a detailed analysis of the taphonomic history of both samples.Bone fragment density is higher in Layer 10 than in Layer 11. Bone densities vary horizontally as well, with Layer 10 showing greater deposition in the exposed areas of the cave. An analysis of long bone breakage patterns indicates that non-nutritive breakage on the Layers 10 and 11 samples was present but not intense. Size 1 mammals were predominantly accumulated by owls and/or other large raptors, not hominids, in Layer 10. Hominids were the predominant accumulator of Sizes 2-4 mammals in Layers 10 and 11 as indicated by the frequency of hammer-stone percussion marks and carnivore toothmarks. After discard by hominids, a significant portion of these remains were discovered and scavenged by carnivores. Overall, the larger mammal fauna of Layer 10 is dominated by Sizes 3 and 4 bovids, mostly young and adult eland, and thus hominids were focusing on the high-ranked prey items. Shaft portions of long bones, the portions with the most flesh, have the highest frequencies of cutmarks. A comparison of the Layers 10 and 11 cutmark frequencies to Selvaggio's (1998) scavenging model shows that the frequencies are significantly outside the range of variation documented in Selavaggio's scavenging sample.

Soluble cell adhesion molecules in hypertriglyceridemia and potential significance on monocyte adhesion

Hypertriglyceridemia may contribute to the development of atherosclerosis by increasing expression of cell adhesion molecules (CAMs). Although the cellular expression of CAMs is difficult to assess clinically, soluble forms of CAMs (sCAMs) are present in the circulation and may serve as markers for CAMs. In this study, we examined the association between sCAMs and other risk factors occurring with hypertriglyceridemia, the effect of triglyceride reduction on sCAM levels, and the role of soluble vascular cell adhesion molecule-1 (sVCAM-1) in monocyte adhesion in vitro. Compared with normal control subjects (n=20), patients with hypertriglyceridemia and low HDL (n=39) had significantly increased levels of soluble intercellular adhesion molecule-1 (sICAM-1) (316+/-28.8 versus 225+/-16.6 ng/mL), sVCAM-1 (743+/-52.2 versus 522+/-43.6 ng/mL), and soluble E-selectin (83+/-5.9 versus 49+/-3.6 ng/mL). ANCOVA showed that the higher sCAM levels in patients occurred independently of diabetes mellitus and other risk factors. In 27 patients who received purified n-3 fatty acid (Omacor) 4 g/d for > or =7 months, triglyceride level was reduced by 47+/-4.6%, sICAM-1 level was reduced by 9+/-3.4% (P=.02), and soluble E-selectin level was reduced by 16+/-3.2% (P<.0001), with the greatest reduction in diabetic patients. These results support previous in vitro data showing that disorders in triglyceride and HDL metabolism influence CAM expression and treatment with fish oils may alter vascular cell activation. In a parallel-plate flow chamber, recombinant sVCAM-1 at the concentration seen in patients significantly inhibited adhesion of monocytes to interleukin-1-stimulated cultured endothelial cells under conditions of flow by 27.5+/-7.2%. Thus, elevated sCAMs may negatively regulate monocyte adhesion.

Effect of green tea rich in gamma-aminobutyric acid on blood pressure of Dahl salt-sensitive rats

gamma-Aminobutyric acid (GABA) is known to be involved in the regulation of blood pressure by modulating the neurotransmitter release in the central and peripheral sympathetic nervous systems. This study investigated the antihypertensive effect of green tea rich in GABA (GABA-rich tea) in young and old Dahl salt-sensitive (S) rats. GABA-rich tea was made by fermenting fresh green tea leaves under nitrogen gas. In experiment 1, 21 11-month-old rats, fed a 4% NaCl diet for 3 weeks, were given water (group W), an ordinary tea solution (group T), or a GABA-rich tea solution (group G) for 4 weeks. The average GABA intake was 4.0 mg/rat per day. After 4 weeks of the treatment, blood pressure was significantly decreased in group G (176 +/- 4; P < .01) compared with group W (207 +/- 9) or group T (193 +/- 5 mm Hg). Plasma GABA levels were more elevated in group G (111 +/- 54) than in group W (not detectable) or group T (14 +/- 8 ng/mL; P < .01 v G). In experiment 2, 21 5-week-old rats, fed a 4% NaCl diet, were divided into groups W, T, and G. The average GABA intake was 1.8 mg/rat per day. Body weight or chow and beverage consumption did not differ significantly among the three groups. After 4 weeks of the treatment, although blood pressure was comparable in groups W and T (165 +/- 3 v 164 +/- 5 mm Hg, mean +/- SE), it was significantly lower in group G (142 +/- 3 mm Hg) than in the other groups (P < .01).(ABSTRACT TRUNCATED AT 250 WORDS)

Cell cycle-specific action of nerve growth factor in PC12 cells: differentiation without proliferation

PC12 cells were manipulated in such a way as to permit the study of differentiation-specific responses independently from proliferative responses. Cells were starved for serum then exposed to nerve growth factor (NGF) or serum. Following addition of serum, cells incorporated thymidine in a synchronous manner. Subsequent to the wave of DNA synthesis, the cell number increased approximately two-fold. Addition of NGF to serum-starved cultures had no measurable effect on either parameter. Neurite outgrowth was more rapid and extensive and appearance of Na+ channels, measured as saxitoxin binding sites, more rapid than when NGF was added to exponentially-growing cells. Epidermal growth factor receptors were heterologously down-regulated by NGF with similar kinetics under both conditions. Induction of the proto-oncogene c-fos by NGF was also greater in the serum-starved cells than in exponentially-growing cultures. These results indicated that serum starvation resulted in synchronisation of the cultures and that NGF action may be cell cycle-specific. Analysis of the cellular response to NGF at different times during the cell cycle showed that c-fos was induced in the G1 phase but not in S or G2. Fluorescence-activated cell sorter analysis demonstrated that addition of NGF to exponentially-growing cells, resulted in their accumulation in a G1-like state. With regard to the study of the mechanism of NGF action, these results illustrate that measurements of NGF effects on specific components in the signal transduction pathway may be confounded by the use of exponentially-growing cultures.

Microwave coagulation therapy for hepatocellular carcinoma

BACKGROUND & AIMS

Surgical resection is not always feasible in patients with hepatocellular carcinoma. Microwave coagulation therapy has been used as an alternative to resection, and its efficacy has been evaluated.

METHODS

Nineteen patients with unresectable hepatocellular carcinoma underwent microwave coagulation therapy through laparotomy (n = 12), laparoscopy (n = 5), or thoracotomy (n = 2) because of advanced liver cirrhosis and/or intrahepatic metastases. One nodule was treated in 13 patients, tumor size ranged from 5 to 90 mm. Patient outcomes were studied.

RESULTS

Microwave coagulation therapy created a reproducible regional necrosis. Fourteen patients underwent potentially curative treatment; the remaining 5 patients underwent palliative treatment (n = 4) or incomplete tumor coagulation (n = 1). Of the 31 nodules treated, 28 underwent complete tumor ablation. Only 2 patients undergoing laparoscopic microwave coagulation therapy developed local recurrence. The coagulated area subsequently shrank. Patients showed rapid recovery without hepatic dysfunction. Thirteen patients, including 2 long-term survivors, are alive either without tumor (n = 10; 14-64 months) or with tumor (n = 3; 17-22 months). Six patients died of hepatocellular carcinoma (n = 4) or liver insufficiency (n = 2).

CONCLUSIONS

This preliminary study suggests the efficacy of microwave coagulation therapy, including safety and potential curability, in patients with hepatocellular carcinoma with advanced liver cirrhosis and multifocal or central tumors.

Intra-articular fractures of the distal aspect of the radius: arthroscopically assisted reduction compared with open reduction and internal fixation

BACKGROUND

There is no consensus that an arthroscopically guided operation can improve the anatomical and functional results of treatment of intra-articular fractures of the distal aspect of the radius. The purpose of the present prospective study was to determine the usefulness of arthroscopically assisted reduction of displaced intra-articular fractures of the distal aspect of the radius by comparing the results of that procedure with those of conventional open reduction and internal fixation.

METHODS

Thirty-four fractures were treated with arthroscopically guided reduction with use of one volar and two dorsal arthroscopic portals. The fractures were pinned, and external fixation was used with or without autogenous bone graft. Intraoperative fluoroscopy was not used. Forty-eight fractures were treated with conventional open reduction and internal fixation with a plate and screws or with pinning, with or without external fixation. The average duration of follow-up for all fractures was thirty-one months.

RESULTS

The scores for overall outcome, assessed with use of the system of Gartland and Werley and that of Green and O'Brien as modified by Cooney et al., demonstrated that the group that had had an arthroscopically assisted procedure had better outcomes than the group that had had conventional open reduction and internal fixation. The group that had had an arthroscopically assisted procedure also had significantly better ranges of flexion-extension and radial-ulnar deviation of the wrist and grip strength (p<0.05). We detected an association between the maximum step and gap displacement and evidence of osteoarthritis of the radiocarpal joint (p<0.001), but we did not find a significant association, with the numbers available, between the scores for osteoarthritis, graded according to the scale of Knirk and Jupiter, and the scores for overall outcome, assessed with the scale of Gartland and Werley and the modified system of Green and O'Brien, in either group (p = 0.376). The radiographic results showed that the patients who had had an arthroscopically assisted procedure had better reduction of volar tilt, ulnar variance, and articular (gap) displacement than did those who had been managed with conventional open reduction and internal fixation (p<0.05 for each comparison).

CONCLUSIONS

An arthroscopically guided operation achieved an accurate reduction of intra-articular fractures of the distal aspect of the radius. Minimum capsular and adjacent soft-tissue scarring reduced postoperative contracture, which improved the overall functional results. We recommend arthroscopically guided reduction and internal fixation not only for young adults but for all patients who are less than seventy years old and have an intra-articular fracture of the distal part of the radius with more than one millimeter of displacement on plain radiographs.