Identification and purification of natural killer cell stimulatory factor (NKSF), a cytokine with multiple biologic effects on human lymphocytes

We have identified and purified a novel cytokine, NK cell stimulatory factor (NKSF), from the cell-free supernatant fluid of the phorbol diester-induced EBV-transformed human B lymphoblastoid cell line RPMI 8866. NKSF activity is mostly associated to a 70-kD anionic glycoprotein. The purified 70-kD protein, isolated from an SDS-PAGE gel, yields upon reduction two small species of molecular masses of 40 and 35 kD, suggesting that this cytokine is a heterodimer. When added to human PBL, purified NKSF preparations induce IFN-gamma production and synergize with rIL-2 in this activity, augment the NK cell-mediated cytotoxicity of PBL preparations against both NK-sensitive and NK-resistant target cell lines, and enhance the mitogenic response of T cells to mitogenic lectins and phorbol diesters. The three activities remain associated through different purification steps resulting in a 9,200-fold purification, and purified NKSF mediates the three biological activities at concentrations in the range of 0.1-10 pM. These data strongly suggest that the same molecule mediates these three activities, although the presence of traces of contaminant peptides even in the most purified NKSF preparations does not allow us to exclude the possibility that distinct biologically active molecules have been co-purified. The absence of other known cytokines in the purified NKSF preparations, the unusual molecular conformation of NKSF, the high specific activity of the purified protein, and the spectrum of biological activities distinguish NKSF from other previously described cytokines.

Prospective randomized trial of docetaxel versus doxorubicin in patients with metastatic breast cancer

PURPOSE

This phase III study compared docetaxel and doxorubicin in patients with metastatic breast cancer who had received previous alkylating agent-containing chemotherapy.

PATIENTS AND METHODS

Patients were randomized to receive an intravenous infusion of docetaxel 100 mg/m(2) or doxorubicin 75 mg/m(2) every 3 weeks for a maximum of seven treatment cycles.

RESULTS

A total of 326 patients were randomized, 165 to receive doxorubicin and 161 to receive docetaxel. Overall, docetaxel produced a significantly higher rate of objective response than did doxorubicin (47.8% v 33.3%; P =.008). Docetaxel was also significantly more active than doxorubicin in patients with negative prognostic factors, such as visceral metastases (objective response, 46% v 29%) and resistance to prior chemotherapy (47% v 25%). Median time to progression was longer in the docetaxel group (26 weeks v 21 weeks; difference not significant). Median overall survival was similar in the two groups (docetaxel, 15 months; doxorubicin, 14 months). There was one death due to infection in each group, and an additional four deaths due to cardiotoxicity in the doxorubicin group. Although neutropenia was similar in both groups, febrile neutropenia and severe infection occurred more frequently in the doxorubicin group. For severe nonhematologic toxicity, the incidences of cardiac toxicity, nausea, vomiting, and stomatitis were higher among patients receiving doxorubicin, whereas diarrhea, neuropathy, fluid retention, and skin and nail changes were higher among patients receiving docetaxel.

CONCLUSION

The observed differences in activity and toxicity profiles provide a basis for therapy choice and confirms the rationale for combination studies in early breast cancer.

A new adenoviral vector: Replacement of all viral coding sequences with 28 kb of DNA independently expressing both full-length dystrophin and beta-galactosidase

Adenoviral vector-mediated gene transfer offers significant potential for gene therapy of many human diseases. However, progress has been slowed by several limitations. First, the insert capacity of currently available adenoviral vectors is limited to 8 kb of foreign DNA. Second, the expression of viral proteins in infected cells is believed to trigger a cellular immune response that results in inflammation and in only transient expression of the transferred gene. We report the development of a new adenoviral vector that has all viral coding sequences removed. Thus, large inserts are accommodated and expression of all viral proteins is eliminated. The first application of this vector system carries a dual expression cassette comprising 28.2 kb of nonviral DNA that includes the full-length murine dystrophin cDNA under control of a large muscle-specific promoter and a lacZ reporter construct. Using this vector, we demonstrate independent expression of both genes in primary mdx (dystrophin-deficient) muscle cells.

Publication bias and clinical trials

A study was performed to evaluate the extent to which the medical literature may be misleading as a result of selective publication of randomized clinical trials (RCTs) with results showing a statistically significant treatment effect. Three hundred eighteen authors of published trials were asked whether they had participated in any unpublished RCTs. The 156 respondents reported 271 unpublished and 1041 published trials. Of the 178 completed unpublished RCTs with a trend specified, 26 (14%) favored the new therapy compared to 423 of 767 (55%) published reports (p less than 0.001). For trials that were completed but not published, the major reasons for nonpublication were "negative" results and lack of interest. From the data provided, it appears that nonpublication was primarily a result of failure to write up and submit the trial results rather than rejection of submitted manuscripts. The results of this study imply the existence of a publication bias of importance both to meta-analysis and the interpretation of statistically significant positive trials.

Influence of age and hemodynamics on myocardial blood flow and flow reserve

BACKGROUND

Aging is associated with changes of the systolic blood pressure that may increase cardiac work and myocardial blood flow at rest and reduce the myocardial flow reserve. This might be misinterpreted as age-related impairment of the coronary vasodilator capacity.

METHODS AND RESULTS

Myocardial blood flow was quantified at rest and after administration of intravenous dipyridamole in 40 healthy volunteers (12 women and 28 men) with 13N-ammonia and positron emission tomography. Eighteen of the normal subjects were less than and 22 were older than 50 years (31 +/- 9 versus 64 +/- 9 years). The resting rate-pressure product was lower in the younger than in the older subjects (6895 +/- 1070 versus 8634 +/- 1890; P < 0.01). Myocardial blood flow at rest averaged 0.76 +/- 0.17 mL.min-1.g-1 in the younger volunteers and 0.92 +/- 0.25 mL.min-1.g-1 in the older volunteers (P < 0.05). Hyperemic blood flows did not differ between younger and older subjects (3.0 +/- 0.8 versus 2.7 +/- 0.6 mL.min-1.g-1; P = NS); however, minimal coronary resistance was higher in the older subjects. Corrected for indexes of coronary driving pressure, hyperemic flow was lower in older than in younger normal subjects. The higher resting blood flows combined with similar hyperemic flows resulted in a lower myocardial flow reserve in the older than in the younger normal subjects (4.1 +/- 0.9 versus 3.0 +/- 0.70; P < 0.0001). The flow reserve was more closely correlated with resting than with hyperemic blood flows.

CONCLUSIONS

Aging does not alter significantly dipyridamole-induced hyperemic flows; although coronary vascular resistance after dipyridamole was somewhat increased in older subjects. The gradual decline of the myocardial blood flow reserve correlates with an age-related increase of baseline myocardial work and blood flow. These findings suggest that the reduced flow reserve with age is primarily due to increased cardiac work and blood flow at rest rather than to an abnormal vasodilator capacity.

CD1-restricted CD4+ T cells in major histocompatibility complex class II-deficient mice

Rather unexpectedly, major histocompatibility complex class II-deficient mice have a significant population of peripheral CD4+ T lymphocytes. We have investigated these cells at the population and clonal levels. CD4+ T lymphocytes from class II-deficient animals are thymically derived, appear early in ontogeny, exhibit the phenotype of resting memory cells, are potentially functional by several criteria, and have a diverse T cell receptor repertoire. They do not include substantially elevated numbers of NK1.1+ cells. Hybridomas derived after polyclonal stimulation of the CD4+ lymphocytes from class II-deficient animals include a subset with an unusual reactivity pattern, responding to splenocytes from many mouse strains including the strain of origin. Most members of this subset recognize the major histocompatibility complex class Ib molecule CD1; their heterogeneous reactivities and T cell receptor usage further suggest the involvement of peptides and/or highly variable posttranslational modifications.

Defective presentation to class I-restricted cytotoxic T lymphocytes in vaccinia-infected cells is overcome by enhanced degradation of antigen

Vaccinia infection interferes with the presentation of influenza Haemagglutinin (HA) and Nucleoprotein (NP) to class I-restricted CTL. The inhibitory effect is selective for certain epitopes, and is more profound during the late phase of infection. For influenza A/NT/60/68 NP, the block is present during both early and late phases of infection, and is selective for the COOH-terminal epitope defined by peptide 366-379, having no detectable effect on the presentation of the NH2-terminal epitope 50-63. The presentation of HA is inhibited only during the late phase of vaccinia infection. For both proteins, presentation is partially (NP) or completely (HA) restored by expression of rapidly degraded protein fragments in the vaccinia infected target cell. For HA, deletion of the NH2-terminal signal sequence completely overcomes the block. For NP, either a large NH2-terminal deletion or the construction of a rapidly degraded ubiquitin-NP fusion protein partially restores presentation. These results illustrate the relationship between degradation of viral proteins in the cytoplasm of an infected cell and recognition of epitopes at the cell surface by class I-restricted T cells.

Targeting the mammalian target of rapamycin (mTOR): a new approach to treating cancer

mTOR is a downstream mediator in the PI3K/Akt signalling pathway, which plays a critical role in regulating basic cellular functions. These include cell proliferation, survival, mobility and angiogenesis. Rapamycin and its analogues (CCI-779, RAD001 and AP23573) have specific antagonistic action on the function of mTOR. This leads to inhibition of the downstream signalling elements and results in the cell cycle arrest in the G1 phase. This group of drugs may have a place in Oncology for the treatment of cancers, which occur as a result of increased activity of the PI3 kinase/Akt/m-TOR pathway. The basic structure of the pathway was reviewed in this article, together with results of the clinical studies targeting mTOR for cancer therapy. This is an exciting area for development and poses many challenges to researchers.

Prostaglandin E2 enhances cortical bone mass and activates intracortical bone remodeling in intact and ovariectomized female rats

To assess the efficacy of prostaglandin E2 (PGE2) in augmenting cortical bone mass, graded doses of PGE2 were subcutaneously administered for 30 days to seven-month old sham-ovariectomized (SHAM) and ovariectomized (OVX) rats. Both groups were operated at three months of age. Histomorphometric analyses of double fluorescent labeled tibial shafts were performed on basal control, OVX, and SHAM rats treated with 0, 0.3, 1, 3, and 6 mg PGE2/kg/d for 30 days. Baseline aging data showed increased cortical tissue and cortical bone area and reduced bone formation parameters at the periosteal and endocortical bone envelopes between three and eight months of age. The tibial shafts of OVX rats compared to SHAM controls showed elevated periosteal mineral apposition rate and endocortical bone formation parameters. PGE2 administration to OVX and SHAM rats increased cortical bone by the addition of new circumferential bone on the endocortical and periosteal surfaces, as well as woven cancellous bone in the marrow region. Stimulated osteoblastic recruitment and activity enhanced bone formation at all bone surfaces. The new bone was both lamellar and woven in nature. PGE2 treatment also activated intracortical bone remodeling (not seen in untreated eight-month old rats), creating a porous cortex. Thus, PGE2 administration activated cortical bone modeling in the formation mode (A----F), as well as intracortical bone remodeling (A----R----F). PGE2 administration to OVX rats resulted in more intracortical bone remodeling, periosteal bone formation, and new cancellous bone production than observed in PGE2 treated controls. The findings that PGE2 administration to OVX and intact female rats increases cortical bone mass, coupled with observations that mouse, rat, dog, and man respond similarly to PGE2, suggest that PGE2 administration may be useful in the prevention and treatment of postmenopausal osteoporosis.

Frequency and clinical determinants of dementia after ischemic stroke

OBJECTIVE

To investigate the frequency and clinical determinants of dementia after ischemic stroke.

METHODS

The authors administered neurologic, neuropsychological, and functional assessments to 453 patients (age 72.0 +/- 8.3 years) 3 months after ischemic stroke. They diagnosed dementia using modified Diagnostic and Statistical Manual of Mental Disorders, 3rd ed., revised criteria requiring deficits in memory and two or more additional cognitive domains as well as functional impairment.

RESULTS

The authors diagnosed dementia in 119 of the 453 patients (26.3%). Regarding dementia subtypes, 68 of the 119 patients (57.1%) were diagnosed with vascular dementia, 46 patients (38.7%) were diagnosed with AD with concomitant stroke, and 5 patients (4.2%) had dementia for other reasons. Logistic regression suggested that dementia was associated with a major hemispheral stroke syndrome (OR 3.0), left hemisphere (OR 2.1) and right hemisphere (OR 1.8) infarct locations versus brainstem/cerebellar locations, infarcts in the pooled anterior and posterior cerebral artery territories versus infarcts in other vascular territories (OR 1.7), diabetes mellitus (OR 1.8), prior stroke (OR 1.7), age 80 years or older (OR 12.7) and 70 to 79 years (OR 3.9) versus 60 to 69 years, 8 or fewer years of education (OR 4.1) and 9 to 12 years of education (OR 3.0) versus 13 or more years of education, black race (OR 2.6) and Hispanic ethnicity (OR 3.1) versus white race, and northern Manhattan residence (OR 1.6).

CONCLUSIONS

Dementia is frequent after ischemic stroke, occurring in one-fourth of the elderly patients in the authors' cohort. The clinical determinants of dementia include the location and severity of the presenting stroke, vascular risk factors such as diabetes mellitus and prior stroke, and host characteristics such as older age, fewer years of education, and nonwhite race/ethnicity. The results also suggest that concomitant AD plays an etiologic role in approximately one-third of cases of dementia after stroke.

The natural history of CADASIL: a pooled analysis of previously published cases

BACKGROUND AND PURPOSE

Although numerous families with cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) have been reported, our understanding of the disease remains incomplete. Thus, we performed this study to investigate the phenotypic range and natural history of CADASIL.

METHODS

We performed a pooled analysis of previously published cases.

RESULTS

We identified 105 symptomatic patients in 33 families. Vascular risk factors were uncommon, with hypertension reported in only 8 patients. The mean age of symptom onset was 36. 7+/-12.9 years. Stroke or transient ischemic attack was an initial symptom in 45 patients, with a mean age of onset of 41.2+/-9.2 years. Migraine was also a common initial symptom, reported by 42 patients at a younger mean age of 28.3+/-11.7 years. Other initial symptoms included depression in 9 patients, cognitive impairment in 6 patients, and seizures in 3 patients. Regarding clinical course, 71 patients experienced a stroke or transient ischemic attack, and 52 of those patients had 1 or more recurrent ischemic events. Dementia was reported in 44 patients. Only 3 additional patients experienced migraine at a later time, while 13 additional patients developed depression. Six patients had seizures. Twenty-two of the 105 patients had died, with a mean age of death of 54.8+/-10.6 years. Nineteen of those 22 patients had experienced a stroke or transient ischemic attack and 19 patients were demented.

CONCLUSIONS

CADASIL typically becomes evident in early or middle adulthood with migraine or an ischemic event, later manifests itself through recurrent subcortical ischemic strokes leading to a stepwise decline and dementia, and results in reduced survival.

Hypocaloric total parenteral nutrition: effectiveness in prevention of hyperglycemia and infectious complications--a randomized clinical trial

OBJECTIVE

To determine whether the frequency rate of hyperglycemia and infectious complications can be reduced by an underfeeding strategy in patients requiring total parenteral nutrition (TPN), without deleterious effects on nitrogen balance.

DESIGN

Prospective, randomized, controlled nonblinded trial.

SETTING

A university-affiliated teaching hospital with a dedicated TPN service.

PATIENTS

TPN was initiated in 40 adult patients and continued for > or =5 days.

INTERVENTION

Two different TPN feeding strategies were compared: hypocaloric feeding (1 L containing 70 g protein and 1000 kcal) and standard weight-based regimen, begun in similar amounts initially, but advanced in increments toward 25 kcal and 1.5 g protein/kg dry (or adjusted ideal) weight.

MEASUREMENTS AND MAIN RESULTS

We evaluated the frequency rate of hyperglycemia, average blood glucose, numbers and types of infections while receiving nutritional support and nitrogen balance after 5 days of TPN. There were significant differences between the quantities of calories, dextrose, fat, and protein provided to the two groups. However, average blood glucose, frequency rate of hyperglycemia, and infection rates (from intravenous catheter, pneumonia, and wound/abdominal collection) were similar in each group. The control group showed a trend toward a higher insulin requirement. Nitrogen balance, only available as a subset, was significantly more negative in the hypocaloric group.

CONCLUSIONS

Provision of TPN to a goal of 25 kcal/kg was not associated with more hyperglycemia or infections than a deliberate underfeeding strategy. A regimen of 1.5 g/kg protein in conjunction with 25 kcal/kg did, however, provide significant nutritional benefit in terms of nitrogen balance in comparison with hypocaloric TPN.

Incidence, prognosis, and etiology of end-stage liver disease in patients receiving home total parenteral nutrition

BACKGROUND

Elevations in liver function tests have been reported in patients receiving total parenteral nutrition (TPN). The clinical aspects of end-stage liver disease (ESLD) associated with the prolonged use of home TPN have not been fully clarified. In previous series patients with duodenocolostomies appeared to be at higher risk than persons with some jejunum or ileum remaining in situ.

METHODS

The records of 42 patients treated with home TPN for more than 1 year were examined. This constituted 283 person-years of home TPN. Patients with duodenocolostomies were examined as a separate group on the basis of the literature experience.

RESULTS

Six of 42 patients who received chronic home TPN had ESLD with 100% subsequent mortality, at an average of 10.8 +/- 7.1 months after the initial bilirubin elevation. Thirteen of 42 patients had superior mesenteric artery or vein thrombosis (SMT) leading to duodenocolostomy. In 8 of these 13 patients with SMT and underlying inflammatory or malignant disorder, 2 had ESLD. The remaining 5 SMT patients who had only minimal liver enzyme elevation over 13.6 +/- 6.7 (range 3 to 19) years of home TPN were significantly younger (36 +/- 7 years vs 64 +/- 13 years) and did not have underlying inflammation either by clinical diagnosis or as reflected in the high normal serum albumin level (> or = 4.0 g/dL). Despite their extreme short bowel syndrome and long exposure to home TPN, ESLD did not develop.

CONCLUSIONS

Approximately 15% of patients who receive prolonged TPN have ESLD with a high rate of morbidity and mortality. The combination of chronic inflammation and the short bowel syndrome appears to be necessary for the development of ESLD with prolonged home TPN.

Quantitative objective markers for upper and lower motor neuron dysfunction in ALS

OBJECTIVE

To investigate the value of objective biomarkers for upper (UMN) and lower (LMN) motor neuron involvement in ALS.

METHODS

We prospectively studied 64 patients with ALS and its subsets using clinical measures, proton MR spectroscopic imaging ((1)H MRSI), diffusion tensor imaging, transcranial magnetic stimulation, and the motor unit number estimation (MUNE) at baseline and every 3 months for 15 months and compared them with control subjects.

RESULTS

(1)H MRSI measures of the primary motor cortex N-acetyl-aspartate (NAA) concentration were markedly reduced in ALS (p = 0.009) and all UMN syndromes combined (ALS, familial ALS [fALS], and primary lateral sclerosis; p = 0.03) vs control values. Central motor conduction time to the tibialis anterior was prolonged in ALS (p < 0.0005) and combined UMN syndromes (p = 0.001). MUNE was lower in ALS (p < 0.0005) and all LMN syndromes combined (ALS, fALS, and progressive muscular atrophy; p = 0.001) vs controls. All objective markers correlated well with the ALS Functional Rating Scale-Revised, finger and foot tapping, and strength testing, suggesting these markers related to disease activity. Regarding changes over time, MUNE changed rapidly, whereas neuroimaging markers changed more slowly and did not significantly differ from baseline.

CONCLUSIONS

(1)H MR spectroscopic imaging measures of the primary motor cortex N-acetyl-aspartate (NAA) concentration and ratio of NAA to creatine, central motor conduction time to the tibialis anterior, and motor unit number estimation significantly differed between ALS, its subsets, and control subjects, suggesting they have potential to provide insight into the pathobiology of these disorders.

Colonic motility and transit in health and ulcerative colitis

Preprandial and postprandial colonic motility and transit (scintigraphy), with respect to the splenic flexure, were studied in 10 patients with ulcerative colitis and in 9 healthy subjects. The healthy subjects had a postprandial increase in intraluminal pressure that was significantly (P less than 0.03) greater in the descending colon than in other regions of the colon. In ulcerative colitis, the pressure was decreased in all regions compared with healthy subjects, with no significant pressure gradient among different regions. In normal subjects, transit was quiescent during fasting; eating stimulated both antegrade and retrograde transit. In ulcerative colitis, transit was variable before as well as after the meal. Both healthy subjects and patients with ulcerative colitis had more rapid emptying from the splenic flexure into the sigmoid than into the transverse colon. More frequent, low-amplitude, postprandial propagating contractions occurred in ulcerative colitis (P less than 0.05) than in healthy subjects. Propagating contractions were always antegrade and caused a rapid movement of the tracer into the sigmoid. In conclusion, ulcerative colitis is characterized by (a) decreased contractility, (b) increased low-amplitude propagating contractions, and (c) variable transit. These disturbances may accentuate the diarrhea in ulcerative colitis.

Atrial septal aneurysm: a new classification in two hundred five adults

Atrial septal aneurysm is a localized "saccular" deformity, generally at the level of the fossa ovalis, which protrudes to the right or the left atrium or both. For 39 months we prospectively analyzed 205 consecutive patients in whom atrial septal aneurysm was diagnosed echocardiographically. The direction and movement of atrial septal aneurysms were carefully studied in multiple views, and, according to our findings, we now propose a new classification: type 1R if the bulging is in the right atrium only, type 2L if the bulging is in the left atrium only, type 3RL if the major excursion bulges to the right atrium and the lesser excursion bulges toward the left, type 4LR if the maximal excursion of the atrial septal aneurysm is toward the left atrium with a lesser excursion toward the right atrium, type 5 if the atrial septal aneurysm movement is bidirectional and equidistant to both atria during the cardiorespiratory cycle. We found an incidence of 1.9%, a mean age of 63 years (25 to 97 years), a female/male ratio of 2:1, valvular regurgitation 74%, hypertension 64%, left ventricular hypertrophy 38%, coronary heart disease 32%, patent foramen ovale 32%, pulmonary hypertension 31%, stroke 20%, dysrhythmias 16%, valvular prolapse 15%, and atrial septal defect 3%. No differences were found between mobile and motionless types of atrial septal aneurysm. However, differences were found between predominantly left bulging or right bulging atrial septal aneurysm (134 versus 57 patients), as well as other variables. All types of atrial septal aneurysm have particular clinical or echocardiographic characteristics. The new classification is a complete, simple, and practical form. Atrial septal aneurysm is associated with congenital and acquired heart diseases but also can present as an isolated abnormality.

Diastolic dysfunction and natriuretic peptides in systolic heart failure. Higher ANP and BNP levels are associated with the restrictive filling pattern

BACKGROUND

Left ventricular diastolic dysfunction is common in patients with systolic heart failure and the restrictive type of filling pattern appears to be associated with increased cardiac mortality. Both artrial and brain (or ventricular) natriuretic peptides are also proven markers of the severity of heart failure. The aim of this study was to determine in a large cohort of patients with systolic heart failure whether diastolic abnormalities, and in particular the restrictive filling pattern of transmitral flow velocity, correlate with plasma atrial and brain natriuretic peptide levels.

METHODS

Sixty-eight consecutive patients with symptomatic systolic heart failure (ejection fraction < 0.5) underwent two-dimensional Doppler echocardiography of left ventricular systolic and diastolic function, together with measurement of atrial and brain natriuretic peptides.

RESULTS

The restrictive filling pattern was present in 62%, the abnormal relaxation pattern in 31% and only 7% were normal. Atrial and brain natriuretic peptide (ANP/BNP) levels were significantly higher in the restrictive compared to the abnormal relaxation group (ANP: 202.2 +/- 31.7 vs 102.5 +/- 22.1 pg.ml-1, P = 0.012; BNP: 277.8 +/- 27.7 vs 162.4 +/- 21.9 pg.ml-1, P = 0.002). In addition, a restrictive filling pattern was associated with lower ejection fractions (P = 0.026), higher pulmonary artery systolic pressure (P < 0.001), larger left atrial size (P = 0.044), and were more likely to be in New York Heart Association class III or IV than those with an abnormal relaxation pattern (P = 0.007). Both atrial and brain natriuretic peptides correlated inversely with ejection fraction (P < 0.001), fractional shortening (P < 0.001), and positively with pulmonary artery pressure (P = 0.004 and 0.001 respectively). There were no significant correlations between single diastolic parameters and atrial or brain natriuretic peptide levels for the total patient group except between mitral peak A wave velocity and brain natriuretic peptides (r = -0.3, P = 0.01). For those with abnormal relaxation pattern mitral, valve E-wave deceleration time correlated significantly with both atrial and brain natriuretic peptide levels (P < 0.01).

CONCLUSIONS

This study confirms that the restrictive filling pattern of transmitral flow velocity is a marker of more severe heart failure, as indicated by its association with higher atrial and brain natriuretic peptide levels, lower ejection fraction and higher pulmonary artery pressure. Thus, this easily obtained Doppler-derived marker of diastolic dysfunction is useful for identifying those patients with more severe heart failure.

c-myc oncogene expression in colorectal cancer

The pattern of c-myc gene organization and expression has been examined in resected colonic tumors and in the adjacent normal colon from 15 patients undergoing radical surgery. DNA hybridization showed no evidence of gene amplification or rearrangement. Transcripts of the c-myc messenger ribonucleic acid (mRNA) were elevated up to 32-fold in 12 of 15 tumors. The gene product, p62c-myc, was detected by both immunoblotting and immunohistology using a monoclonal antibody raised against a synthetic peptide immunogen. There was close correlation between c-myc mRNA copy number and p62c-myc abundance. Three well differentiated tumors contained high levels of transcript and protein, whereas four poorly differentiated tumors had the lowest levels. The assay of oncogene products may provide new biologically relevant tumor markers for determining prognosis and guiding treatment.

The Hong Kong diastolic heart failure study: a randomised controlled trial of diuretics, irbesartan and ramipril on quality of life, exercise capacity, left ventricular global and regional function in heart failure with a normal ejection fraction

BACKGROUND

Although heart failure with a preserved or normal ejection fraction (HFNEF or diastolic heart failure) is common, treatment outcomes on quality of life and cardiac function are lacking. The effect of renin-angiotensin blockade by irbesartan or ramipril in combination with diuretics on quality of life (QoL), regional and global systolic and diastolic function was assessed in HFNEF patients.

METHODS

150 patients with HFNEF (LVEF >45%) were randomised to (1) diuretics alone, (2) diuretics plus irbesartan, or (3) diuretics plus ramipril. QoL, 6-minute walk test (6MWT) and Doppler echocardiography were performed at baseline, 12, 24 and 52 weeks.

RESULTS

The QoL score improved similarly in all three groups by 52 weeks (-46%, 51%, and 50% respectively, all p<0.01), although 6MWT increased only slightly (average +3-6%). Recurrent hospitalisation rates were equal in all groups (10-12% in 1 year). At 1 year, LV dimensions or LVEF had not changed in any group, though both systolic and diastolic blood pressures were lowered in all three groups from 4 weeks onwards. At baseline both mean peak systolic (Sm) and early diastolic (Em) mitral annulus velocities were reduced, and increased slightly in the diuretic plus irbesartan (Sm 4.5 (SEM 0.17) to 4.9 (SEM 0.16) cm/sec; Em 3.8 (SEM 0.25) to 4.2 (SEM 0.25) cm/sec) and ramipril (Sm 4.5 (SEM 0.24) to 4.9 (SEM 0.20) cm/sec; Em 3.3 (SEM 0.25) to 4.04 (SEM 0.32) cm/sec) groups (both p<0.05). NT-pro-BNP levels were raised at baseline (595 (SD 905) pg/ml; range 5-4748) and fell in the irbesartan (-124 (SD 302) pg/ml, p = 0.01) and ramipril (-173 (SD 415) pg/ml, p = 0.03) groups only.

CONCLUSIONS

In this typically elderly group of HF patients with normal LVEF, diuretic therapy significantly improved symptoms and neither irbesartan nor ramipril had a significant additional effect. However, diuretics in combination with irbesartan or ramipril marginally improved LV systolic and diastolic longitudinal LV function, and lowered NT-proBNP over 1 year.

Elderly suicide in Hong Kong--a case-controlled psychological autopsy study

OBJECTIVE

To examine some of the risk factors for late life suicide in Hong Kong Chinese using a case-controlled psychological autopsy approach.

METHOD

Informants of 70 subjects aged 60 or above who had committed suicide as well as a community sample of 100 elderly controls were interviewed. Subjects and controls were assessed for the presence of mental illness, history of suicide attempt and data on health care utilization.

RESULTS

Eighty-six per cent of suicide subjects suffered from a psychiatric problem before committing suicide, compared with 9% of control subjects. Among the psychiatric problems, major depression was the commonest diagnosis. Seventy-seven per cent of suicide subjects had consulted a doctor within 1 month of suicide. One-third of suicide subjects had a history of suicide attempt. Rates of current psychiatric diagnosis, rates of medical consultation and history of suicide attempt are all significantly higher in suicide subjects than controls.

CONCLUSION

Our findings support the view that depressive disorders and a past history of suicide attempt are risk factors of late-life suicide in the Chinese population of Hong Kong, similar to findings in western studies.

Noninvasive ventilatory support during sleep improves respiratory failure in kyphoscoliosis

We investigated the effect on daytime respiratory function and quality of sleep, of providing adequate ventilation either by intermittent positive pressure ventilation (IPPV) or by continuous positive airways pressure (CPAP) both administered through a nose mask in a group of seven patients with severe thoracic kyphoscoliosis. All night control sleep studies were performed with and without ventilatory assistance. Patients underwent standard polysomnography including all night measurements of transcutaneous CO2 (tcCO2) and arterial oxyhemoglobin saturation (SaO2). Awake arterial blood gas tensions (ABGs), respiratory muscle strength (Pmus), and lung function tests were measured in the sitting position. Follow-up studies after three months of treatment showed normal sleep patterns, improvement in daytime ABGs, lung volumes, and respiratory muscle strength. We concluded that maintenance of nocturnal ventilation by either nasal CPAP or nasal IPPV in patients with nocturnal respiratory failure does significantly improve clinical measurements of respiratory function and quality of sleep.