Nanoparticles containing a liver X receptor agonist inhibit inflammation and atherosclerosis

Liver X receptor (LXR) signaling pathways regulate lipid metabolism and inflammation, which has generated widespread interest in developing synthetic LXR agonists as potential therapeutics for the management of atherosclerosis. In this study, it is demonstrated that nanoparticles (NPs) containing the synthetic LXR agonist GW3965 (NP-LXR) exert anti-inflammatory effects and inhibit the development of atherosclerosis without causing hepatic steatosis. These NPs are engineered through self-assembly of a biodegradable diblock poly(lactide-co-glycolide)-b-poly(ethylene glycol) (PLGA-b-PEG) copolymer. NP-LXR is significantly more effective than free GW3965 at inducing LXR-target gene expression and suppressing inflammatory factors in macrophages in vitro and in vivo. Additionally, the NPs elicit negligible lipogenic gene stimulation in the liver. Using the Ldlr (-/-) mouse model of atherosclerosis, abundant colocalization of fluorescently labeled NPs within plaque macrophages following systemic administration is seen. Notably, six intravenous injections of NP-LXR over 2 weeks markedly reduce the CD68-positive cell (macrophage) content of plaques (by 50%) without increasing total cholesterol or triglycerides in the liver and plasma. Together, these findings identify GW3965-encapsulated PLGA-b-PEG NPs as a promising nanotherapeutic approach to combat atherosclerosis, providing the benefits of LXR agonists without their adverse effects on hepatic and plasma lipid metabolism.

Grey matter volume and thickness abnormalities in young people with a history of childhood abuse

BACKGROUND

Childhood abuse is associated with abnormalities in brain structure and function. Few studies have investigated abuse-related brain abnormalities in medication-naïve, drug-free youth that also controlled for psychiatric comorbidities by inclusion of a psychiatric control group, which is crucial to disentangle the effects of abuse from those associated with the psychiatric conditions.

METHODS

Cortical volume (CV), cortical thickness (CT) and surface area (SA) were measured in 22 age- and gender-matched medication-naïve youth (aged 13-20) exposed to childhood abuse, 19 psychiatric controls matched for psychiatric diagnoses and 27 healthy controls. Both region-of-interest (ROI) and whole-brain analyses were conducted.

RESULTS

For the ROI analysis, the childhood abuse group compared with healthy controls only, had significantly reduced CV in bilateral cerebellum and reduced CT in left insula and right lateral orbitofrontal cortex (OFC). At the whole-brain level, relative to healthy controls, the childhood abuse group showed significantly reduced CV in left lingual, pericalcarine, precuneus and superior parietal gyri, and reduced CT in left pre-/postcentral and paracentral regions, which furthermore correlated with greater abuse severity. They also had increased CV in left inferior and middle temporal gyri relative to healthy controls. Abnormalities in the precuneus, temporal and precentral regions were abuse-specific relative to psychiatric controls, albeit at a more lenient level. Groups did not differ in SA.

CONCLUSIONS

Childhood abuse is associated with widespread structural abnormalities in OFC-insular, cerebellar, occipital, parietal and temporal regions, which likely underlie the abnormal affective, motivational and cognitive functions typically observed in this population.

The activities of some energy-metabolising enzymes in nonsynaptic (free) and synaptic mitochondria derived from selected brain regions

The enzyme complement of two different mitochondrial preparations from adult rat brain has been studied. One population of mitochondria (synaptic) is prepared by the lysis of synaptosomes, the other (non-synaptic or free) by separation from homogenates. These populations have been prepared from distinct regions of the brain: cortex, striatum, and pons and medulla oblongata. The following enzymes have been measured: pyruvate dehydrogenase (EC 1.2.4.1), citrate synthase (EC 4.1.3.7), NAD-linked isocitrate dehydrogenase (EC 1.1.1.41), NADP-linked isocitrate dehydrogenase (EC 1.1.1.42), fumarase (EC 4.2.1.2), NAD-linked malate dehydrogenase (EC 1.1.1.37), D-3-hydroxybutyrate dehydrogenase (EC 1.1.1.30), and mitochondrially bound hexokinase (EC 2.7.1.1) and creatine kinase (EC 2.7.3.2). The nonsynaptic (free) mitochondria show higher enzyme specific activities in the regions studied than the corresponding values recorded for the synaptic mitochondria. The significance of these observations is discussed in the light of the different metabolic activities of the two populations of mitochondria and the compartmentation of the metabolic activities of the brain.

The Caenorhabditis elegans unc-13 gene product is a phospholipid-dependent high-affinity phorbol ester receptor

The Caenorhabditis elegans unc-13 mutant is a member of a class of mutants that have un-coordinated movement. Mutations of the unc-13 gene cause diverse defects in C. elegans, including abnormal neuronal connections and modified synaptic transmission in the nervous system. unc-13 cDNA encodes a protein (UNC-13) of 1734 amino acid residues with a predicted molecular mass of 198 kDa and sequence identity to the C1/C2 regions but not to the catalytic domain of the ubiquitously expressed protein kinase C family [Maruyama & Brenner (1991) Proc. Natl. Acad. Sci. U.S.A. 88, 5729-5733]. To characterize the phorbol ester binding site of the UNC-13 protein, cDNA encoding the C1/C2-like regions (amino acid residues 546-940) was expressed in Escherichia coli and the 43 kDa recombinant protein was purified. Phorbol ester binding to the 43 kDa protein was zinc- and phospholipid-dependent, stereospecific and of high affinity (Kd 67 nM). UNC-13 specific antisera detected a protein of approx. 190 kDa in wild-type (N2) but not in mutant (e1019) C. elegans cell extracts. We conclude that UNC-13 represents a novel class of phorbol ester receptor.

Conjunctival rotation autograft for pterygium. An alternative to conjunctival autografting

OBJECTIVE

To determine the safety and efficacy of conjunctival rotation autografting (CRA) as an alternative to conventional conjunctival autograft after pterygium excision.

DESIGN

Prospective noncomparative case series.

PARTICIPANTS

Consecutive patients seen at the Pterygium Clinic of the Singapore National Eye Centre who were thought to be unsuitable for conventional conjunctival autografting underwent a modified surgical procedure, which the authors describe as CRA. There were 51 rotation autografts performed on 45 eyes of 43 patients.

INTERVENTION

In this procedure, the underlying fibrovascular pterygium tissue was removed and the original epithelium (with minimal subepithelial tissue included) replaced over the bare sclera with a 180 degrees rotation. Surgeries were performed by one surgeon (DT) from April 1995 to May 1996.

MAIN OUTCOME MEASURE

Pterygium recurrence and complications of CRA were measured.

RESULTS

The mean follow-up time was 12 months (range, 2-22 months). There were 46 primary and 5 recurrent pterygia. The indications for CRA were combined cataract and pterygium surgery (39.2%), double pterygia (31.4%), the need to preserve the superior conjunctiva (21.6%), and superior conjunctival scarring (7.8%). There were two recurrences (4% recurrence rate), one occurring at 4 months and the other occurring at 7 months after surgery. No significant complications were encountered. However, 50% of the grafts remained mildly injected for more than 3 months, and some remained injected for up to 13 months after surgery (average of 4 months). Pigmentary changes were also noted in six grafts (12%).

CONCLUSION

Conjunctival rotation autografting is a useful technique of conjunctival grafting in cases in which it is not possible or desirable to use the superior conjunctiva as a donor source.

Human carboxypeptidase E. Isolation and characterization of the cDNA, sequence conservation, expression and processing in vitro

Carboxypeptidase E (CPE), which cleaves C-terminal amino acid residues and is involved in neuropeptide processing, is itself subject to intracellular processing. Human CPE cDNA was isolated and sequence comparisons were made with those of a previously isolated brain cDNA (M1622) encoding rat CPE and of other human carboxypeptidases (M and N). Human (2.5 kb) and rat (2.1 kb) CPE cDNAs approximated to the size of their respective mRNAs; additional sequences were located in putative 5' and 3' untranslated regions of human CPE mRNA. There is 79% sequence similarity between human and rat CPE cDNAs, with greater similarity (89%) over the coding region and short sections of the non-coding sequence. The predicted 476-amino acid-residue sequences of human and rat preproCPEs are highly conserved (96% identity), with lower degree of similarity of the N-terminal signal peptide (76%). Human CPE showed 51% and 43% sequence similarity to human CPN and CPM respectively, with discrete regions of divergence dispersed between the highly conserved mechanistically implicated regions. Antiserum generated from a fusion protein, synthesized in Escherichia coli from constructs of the human cDNA, recognized an approx. 50 kDa membrane protein and a smaller soluble protein in rat and human brain preparations, corresponding to the two forms of native CPE. Human CPE mRNA transcripts directed the synthesis in reticulocyte lysate of a 54 kDa translation product, which in the presence of dog pancreas microsomal membranes was co-translationally processed with cleavage, insertion into membranes and glycosylation. Three processed forms were generated, the largest (56 kDa) and smallest (52 kDa) being equally glycosylated. The membrane association of the processed translation products and of native brain membrane CPE, detected immunologically, was resistant to moderate alkali but not pH 11.5 extraction. These results are consistent with secondary-structure predictions that CPE is a peripheral membrane protein. The dissimilar regions of human carboxypeptidases may provide information on sequences responsible for their different cellular disposition.

Differential expression of forkhead box transcription factors following butylated hydroxytoluene lung injury

The forkhead box (Fox) proteins are a growing family of transcription factors that have important roles in cellular proliferation and differentiation and in organ morphogenesis. The Fox family members hepatocyte nuclear factor (HNF)-3beta (Foxa2) and HNF-3/forkhead homolog (HFH)-8 (FREAC-1, Foxf1) are expressed in adult pulmonary epithelial and mesenchymal cells, respectively, but these cells display only low expression levels of the proliferation-specific HFH-11B gene (Trident, Foxm1b). The regulation of these Fox transcription factors in response to acute lung injury, however, has yet to be determined. We report here on the use of butylated hydroxytoluene (BHT)-mediated lung injury to demonstrate that HFH-11 protein and RNA levels were markedly increased throughout the period of lung repair. The maximum levels of HFH-11 were observed by day 2 following BHT injury when both bronchiolar and alveolar epithelial cells were undergoing extensive proliferation. Although BHT lung injury did not alter epithelial cell expression of HNF-3beta, a 65% reduction in HFH-8 mRNA levels was observed during the period of mesenchymal cell proliferation. HFH-8-expressing cells were colocalized with platelet endothelial cell adhesion molecule-1-positive alveolar endothelial cells and with alpha-smooth muscle actin-positive peribronchiolar smooth muscle cells.

Use of multidimensional separation protocols for the purification of trace components in complex biological samples for proteomics analysis

The routine detection of low abundance components in complex samples for detailed proteomics analysis continues to be a challenge. Whilst the potential of multidimensional chromatographic fractionation for this purpose has been proposed for some years, and was used effectively for the purification to homogeneity of trace components in bulk biological samples for N-terminal sequence analysis, its practical application in the proteomics arena is still limited. This article reviews some of the recent data using these approaches, including the use of microaffinity purification as part of multidimensional protocols for downstream proteomics analysis.

Lanosterol induces mitochondrial uncoupling and protects dopaminergic neurons from cell death in a model for Parkinson's disease

Parkinson's disease (PD) is a neurodegenerative disorder marked by the selective degeneration of dopaminergic neurons in the nigrostriatal pathway. Several lines of evidence indicate that mitochondrial dysfunction contributes to its etiology. Other studies have suggested that alterations in sterol homeostasis correlate with increased risk for PD. Whether these observations are functionally related is, however, unknown. In this study, we used a toxin-induced mouse model of PD and measured levels of nine sterol intermediates. We found that lanosterol is significantly (∼50%) and specifically reduced in the nigrostriatal regions of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-treated mice, indicative of altered lanosterol metabolism during PD pathogenesis. Remarkably, exogenous addition of lanosterol rescued dopaminergic neurons from 1-methyl-4-phenylpyridinium (MPP+)-induced cell death in culture. Furthermore, we observed a marked redistribution of lanosterol synthase from the endoplasmic reticulum to mitochondria in dopaminergic neurons exposed to MPP+, suggesting that lanosterol might exert its survival effect by regulating mitochondrial function. Consistent with this model, we find that lanosterol induces mild depolarization of mitochondria and promotes autophagy. Collectively, our results highlight a novel sterol-based neuroprotective mechanism with direct relevance to PD.

Body mass index and health-related behaviours in a national cohort of 87,134 Thai open university students

BACKGROUND

Thailand is undergoing a health-risk transition with overweight and obesity emerging as an important population health problem. This paper reports on a study of the transition, focusing on "lifestyle" factors such as diet (fried foods, soft drinks, Western-style fast foods) and physical activity (mild, moderate, strenuous exercise, housework/gardening and screen time).

METHODS

A baseline survey was administered to 87 134 adult students from all regions of Thailand attending an open university.

RESULTS

54% of the cohort was female. Participants' median age was 29 years. By self-reported Asian standards, 16% of the sample was obese (body mass index (BMI)>or=25) and 15% overweight at risk (BMI>or=23-24.9). Men were twice as likely as women to be overweight (21% vs 9%) or obese (23% vs 10%). Obesity was associated with urban residence and doing little housework or gardening and with spending more than 4 hours a day watching television or using computers. The latter occurred among 30% of the cohort, with a population attributable fraction (PAF) suggesting that it accounts for 11% of the current problem. Daily consumption of fried food was associated with obesity, and eating fried foods every second day or daily had a PAF of nearly 20%.

CONCLUSIONS

These health-related behaviours underpinning the Thai health transition are associated with increasing obesity. They are modifiable through policies addressing structural issues and with targeted health promotion activities to prevent future obesity gains. Insights into future trends in the Thai health transition can be gained as this student cohort ages.

Randomized clinical trial of Surodex steroid drug delivery system for cataract surgery: anterior versus posterior placement of two Surodex in the eye

OBJECTIVE

To evaluate safety and antiinflammatory efficacy of placing two Surodex (Oculex Pharmaceuticals, Inc., Sunnyvale, CA) in the eye after cataract surgery in comparison with steroid eyedrops and to compare anterior versus posterior chamber placement.

DESIGN

Randomized, masked, controlled trial.

PARTICIPANTS

One hundred four eyes of 104 Asian patients undergoing extracapsular cataract extraction with intraocular lens implantation were examined. Of these, 33 eyes of 33 patients served as control eyes (group A).

INTERVENTION

Two Surodex pellets were inserted in the anterior chamber (AC) of 35 eyes (group B), and two Surodex pellets were inserted in the ciliary sulcus of 36 eyes (group C) at the conclusion of surgery. Control eyes received neither Surodex nor a placebo implant, but were prescribed conventional 0.1% dexamethasone eyedrops four times daily for 4 weeks.

MAIN OUTCOME MEASURES

Anterior chamber flare and cells were graded clinically at the slit lamp. Anterior chamber flare was assessed objectively with the Kowa FC500 Laser Flare Meter (Kowa Co. Ltd, Tokyo, Japan). Intraocular pressure and corneal endothelial specular microscopy with morphometric cell analysis were performed for up to 1 year after surgery.

RESULTS

Lower flare meter readings occurred in both Surodex groups at all postoperative visits, as compared with the dexamethasone eyedrop group, with statistical significance at days 4 (P = 0.001), 8 (P = 0.001), and 15 (P = 0.02). No difference in flare occurred between AC and ciliary sulcus placement. Clinical slit-lamp assessment of anterior chamber flare and cells showed no difference between Surodex-treated eyes and dexamethasone-treated eyes. Nine of 33 eyes (27.3%) in group A required steroid augmentation, as opposed to 4 of 71 eyes (5.6%) in groups B and C. Inflammatory symptoms were reduced in the Surodex-treated eyes, with statistical significance for ocular discomfort (P = 0.001), photophobia (P = 0.04), and lacrimation (P = 0.01). No complications occurred with Surodex-treated eyes, and no significant difference in endothelial cell loss was noted between Surodex-treated eyes and dexamethasone-treated eyes up to 1 year after surgery.

CONCLUSIONS

Intraocular placement of two Surodex is a safe and effective treatment method to reduce intraocular inflammation after cataract surgery and clearly is superior to eyedrops in reducing inflammatory symptoms and aqueous flare as measured with the laser flare meter. No difference in efficacy between AC placement and ciliary sulcus placement of Surodex was detected in this study.

Treatment of the adult respiratory distress syndrome with continuous positive airway pressure

Fifteen patients in the early stages of the adult respiratory distress syndrome with severe hypoxemia who were capable of maintaining adequate spontaneous ventilation were treated with continuous positive airway pressure (CPAP). The optimal level of CPAP was adjusted for each patient to achieve the highest oxygenation with the least adverse hemodynamic effects. The optimal intravascular volume, judged by pulmonary arterial occlusion pressure, was maintained by infusion of lactated Ringer's solution. Application of an optimal CPAP ranging between 10 and 25 cm H2O significantly reduced the intrapulmonary shunt, increased the forced vital capacity, and decreased the respiration rate. The improvement in pulmonary status was achieved with no significant changes in cardiac output or the arterial-mixed venous oxygen content difference. Early application of an adjusted level of positive end-expiratory pressure using CPAP in patients with adequate levels of fluid is an effective and safe method of treating selected groups of patients in the early stages of the adult respiratory distress syndrome.

The Caenorhabditis elegans p21-activated kinase (CePAK) colocalizes with CeRac1 and CDC42Ce at hypodermal cell boundaries during embryo elongation

The p21-activated kinase (PAK) is a downstream target of Rac and CDC42, members of the Ras-related Rho subfamily, that mediates signaling pathway leading to cytoskeletal reorganization. To investigate its function in Caenorhabditis elegans development, we have isolated the cDNA coding for the p21-activated kinase homologue (CePAK) from a C. elegans embryonic cDNA library. This 2.35-kilobase pair cDNA encodes a polypeptide of 572 amino acid residues, with the highly conserved N-terminal p21-binding and the C-terminal kinase domains. Similar to its mammalian and Drosophila counterparts, the CePAK protein expressed in E. coli exhibits binding activity toward GTP-bound CeRac1 and CDC42Ce. Polyclonal antibodies raised against the recombinant CePAK recognize a specific 70-kDa protein from embryonic extracts that displays CeRac1/CDC42Ce-binding and kinase activities. Immunofluorescence analysis indicates that CePAK is specifically expressed at the hypodermal cell boundaries during embryonic body elongation, which involves dramatic cytoskeletal reorganization. Interestingly, CeRac1 and CDC42Ce are found at the same location, which might point to their common involvement in hypodermal cell fusion, a crucial morphogenetic event for nematode development.

Discrepancy between self- and observer ratings of performance in social phobics

Twenty-eight subjects meeting Diagnostic and Statistical Manual of Mental Disorders (rev. 3rd ed.; American Psychiatric Association, 1987) criteria for social phobia and without a comorbid affective disorder and 33 nonclinical controls were asked to present a brief, impromptu speech to a small audience. Speakers themselves, as well as members of the audience, rated each speaker on a public speaking questionnaire that included both specific items (e.g., voice shook) and global items (e.g., appeared confident). For global items, no significant difference was indicated between the two groups on observers' ratings of public speaking performance. However, social phobics rated their own performance worse than did nonclinical controls, and there was a significantly greater discrepancy between self and other ratings for social phobics than controls. Fear of negative evaluation was the only significant predictor of the self-other discrepancy on global items.

Symptoms during normal pregnancy: a prospective controlled study

Symptoms of normal pregnancy have received scant attention in the literature and what is reported is largely unsubstantiated. Yet this is an important aspect of antenatal counselling and care which deserves further investigation if symptoms are to be interpreted correctly. Accordingly, we conducted a prospective controlled study of symptoms during normal pregnancy in both primigravidas and multigravidas. A total of 38 symptoms occurred with a significantly different frequency (mainly increased) in the pregnant subjects in the third trimester compared with the controls. Of these a mean of 24.2 symptoms was experienced by each pregnant woman, double that (mean, 11.2) experienced by healthy nonpregnant controls. The 5 symptoms reported most frequently by the pregnant subjects were frequency of micturition, fatigue, pelvic pressure, insomnia and lower backache. However, a wide range of symptoms involving most body systems were reported. This study has established that symptoms of pregnancy are more numerous than mentioned in current obstetric texts and that they can be attributed to the effects of pregnancy. The third trimester is associated with the greatest number of symptoms and there is a marked decline in their number after delivery.

The regional distribution of monoamine oxidase activities towards different substrates: effects in rat brain of chronic administration of manganese chloride and of ageing

The effects of chronic manganese chloride administration (1 mg MnCl2.4H2O/ml of drinking water) and ageing on the regional distribution of monoamine oxidase (MAO, EC 1.4.3.4) were studied in 2-month- and 24-28-month-old rats. In both the control and Mn-treated rats, the serotonin oxidation (type A) rates decreased in hypothalamus, pons and medulla, striatum, midbrain and cerebral cortex, but not in cerebellum, in ageing. On the other hand the benzylamine oxidation (type B) rates in hypothalamus, striatum and cerebral cortex increased in ageing. In all regions except the cerebellum, there was a uniform decrease in the A/B ratio. This decrease was verified by differential inhibition studies using clorgyline and L-deprenyl, specific type A and type B inhibitors respectively. The dopamine-oxidising rates decreased in all regions, except the cerebral cortex and the cerebellum, in ageing control rats. This age-related decrease was not seen in the striatum and midbrain of manganese-treated rats. In these rats the other effect was an age-related increase in the rate of oxidation of all the amines in the cerebellum, not observed in control rats. These selective effects of manganese are only seen when comparing age-related changes in both groups of animals, since comparison of manganese-treated rats with age-matched controls showed a significant difference only in the rate of serotonin oxidation in the cerebellum of 2-month-old rats. The relationship of these observations to the effects of ageing and manganese encephalopathy on specific amine systems is discussed.

Collapsin response mediator protein switches RhoA and Rac1 morphology in N1E-115 neuroblastoma cells and is regulated by Rho kinase

The formation and directional guidance of neurites involves dynamic regulation of Rho family GTPases. Rac and Cdc42 promote neurite outgrowth, whereas Rho activation causes neurite retraction. Here we describe a role for collapsin response mediator protein (Crmp-2), a neuronal protein implicated in axonal outgrowth and a component of the semaphorin 3A pathway, in switching GTPase signaling when expressed in combination with either dominant active Rac or Rho. In neuroblastoma N1E-115 cells, co-expression of Crmp-2 with dominant active RhoA V14 induced Rac morphology, cell spreading and ruffling (and the formation of neurites). Conversely, co-expression of Crmp-2 with dominant active Rac1 V12 inhibited Rac morphology, and in cells already expressing Rac1 V12, Crmp-2 caused localized peripheral collapse, involving Rho (and Cdc42) activation. Rho kinase was a pivotal regulator of Crmp-2; Crmp-2 phosphorylation was required for Crmp-2/Rac1 V12 inhibition, but not Crmp-2/RhoA V14 induction, of Rac morphology. Thus Crmp-2, regulated by Rho kinase, promotes outgrowth and collapse in response to active Rho and Rac, respectively, reversing their usual morphological effects and providing a mechanism for dynamic modulation of growth cone guidance.

Asthma presentations to emergency departments in western Sydney during the January 1994 Bushfires

BACKGROUND

From 5 to 12 January 1994, the state of New South Wales suffered from the worst bushfires seen this century. High levels of particulate air pollution were recorded in western Sydney from 7 to 14 January 1994, with nephelometry readings reaching 10.24 beta scat (10(-4)/m) and particulate matter < 10 mu readings peaking at 250.00 micrograms/m3. The aim of this study was to determine whether there was an increase in the proportion of asthma presentations to emergency departments (ED) in western Sydney as a result of the bushfire-generated particulate air pollution.

METHOD

We retrospectively analysed the emergency room attendance books for asthma presentations from seven public hospitals serving the Western Sydney and Wentworth Health Areas over two 6-7 week periods, 17 December 1992 to 31 January 1993, and 17 December 1993 to 31 January 1994. Air pollution and meteorological data were obtained from local monitoring stations.

RESULTS

The difference in the proportion of all ED presentations that were due to asthma during the week of the bushfire-generated air pollution, compared with the same week 12 months before, after adjusting for baseline changes over the 12-month period, was 0.0067 (95% CI: -0.0007, 0.0141). The maximum daily nephelometry reading was not a significant predictor of the daily number of asthma presentations to ED in any of the Poisson regression models.

CONCLUSIONS

The bushfire-generated particulate air pollution in January 1994 did not result in an increase in asthma presentations to ED in western Sydney.

Localization of a human heat-shock HSP 70 gene sequence to chromosome 6 and detection of two other loci by somatic-cell hybrid and restriction fragment length polymorphism analysis

The human 70 kdalton heat-shock protein (HSP 70) is a member of a multigene family which is expressed in response to various physiological stresses including elevated temperatures. Using a cloned genomic HSP 70 DNA sequence we demonstrate by somatic cell hybrid and restriction fragment length polymorphism (RFLP) analyses that there are a minimum of three distinct HSP 70 loci in the human genome, one of which is located on chromosome 6.

Long-term outcomes of patients with localized rectal cancer treated with chemoradiation or radiotherapy alone because of medical inoperability or patient refusal

PURPOSE

The standard management of rectal cancer continues to be defined by the results of randomized, clinical trials exploring the optimal timing and use of adjuvant chemotherapy and radiation therapy in relation to surgery. The patient with rectal cancer who is elderly and/or has significant comorbidities and the patient who refuses surgery are clinical contexts for which there is limited current data to guide decision making.

METHODS

A retrospective analysis was performed at six Australian centers of patients with rectal cancer treated with radiation therapy or chemoradiation alone because of excessive operative risk or patient refusal of surgery.

RESULTS

We identified 48 patients treated between August 1998 and June 2005 with a median age of 76 (range, 49-94) years. Twenty-four patients (50 percent) were considered medically inoperable and 24 patients refused surgery. Treatment was with chemoradiation (with 5-fluorouracil) in 36 patients and radiotherapy alone in 12 patients; 93 percent completed the planned therapy. A clinical complete response was seen in 56 percent and a partial response in 30 percent of patients. At a median follow-up of 49 months, 18 patients have disease progression, including 10 of 24 in the medically inoperable group and 8 of 24 in the refused surgery group. Of the 25 deceased patients, 16 died from progressive disease and 9 from noncancer causes.

CONCLUSIONS

Chemoradiation or radiotherapy alone is a safe alternative that results in significant progression-free and overall survival times in patients who are considered medically inoperable or refuse to undergo surgery. Ultimately, however, many patients will progress.