A Phase 2 Randomized, Double-Blind, Placebo-Controlled Trial of the Monoclonal Antibody MHAA4549A in Patients With Acute Uncomplicated Influenza A Infection

Background

MHAA4549A, a human monoclonal antibody targeting the influenza A hemagglutinin stalk, neutralizes influenza A virus in animal and human volunteer challenge studies. We investigated the safety and tolerability, efficacy, and pharmacokinetics of MHAA4549A in outpatients with acute, uncomplicated influenza A infection.

Methods

This was a phase 2, randomized, double-blind, placebo-controlled trial of single intravenous (IV) doses of 3600 mg or 8400 mg of MHAA4549A or IV placebo in adult outpatients testing positive for influenza A. Patients were enrolled across 35 sites in 6 countries. Randomization and dosing occurred within ≤72 hours of symptom onset; the study duration was 14 weeks. The primary end point was the nature and frequency of adverse events (AEs). Secondary end points included median time to alleviation of all influenza symptoms, effects on nasopharyngeal viral load and duration of viral shedding, and MHAA4549A serum pharmacokinetics.

Results

Of 125 randomized patients, 124 received study treatment, with 99 confirmed positive for influenza A by central testing. The frequency of AEs between the MHAA4549A and placebo groups was similar; nausea was most common (8 patients; 6.5%). MHAA4549A serum exposure was confirmed in all MHAA4549A-treated patients and was dose-proportional. No hospitalizations or deaths occurred. Between the MHAA4549A and placebo groups, no statistically significant differences occurred in the median time to alleviation of all symptoms, nasopharyngeal viral load, or duration of viral shedding.

Conclusions

While MHAA4549A was safe and well tolerated with confirmed exposure, the antibody did not improve clinical outcomes in patients with acute uncomplicated influenza A infection.

AB0948 TIME TO CONSIDER HYPERMOBILITY AS A CAUSE OF SYMPTOMS IN PATIENTS PRESENTING TO EARLY ARTHRITIS CLINICS: A RETROSPECTIVE ANALYSIS OF 279 PATIENTS

Background:

Joint hypermobility is a common, although largely ignored physical sign. It is often asymptomatic but can be associated with significant musculoskeletal symptoms. Joint hypermobility may also be a feature of an underlying genetic disorder and patients may present with arthralgia, recurrent soft tissue injuries and intermittent joint swelling due to mechanical instability and poor proprioception. At University College London Hospital, we run a national service for the diagnosis and management of patients with hypermobility related disorders including hypermobility spectrum disorders, Ehlers-Danlos syndromes and Marfan syndrome. Over the years we observed that a significant number of our patients had been referred to the early arthritis clinics years prior to the recognition of their hypermobility. For example, one patient with a vascular type of Ehlers-Danlos syndrome EDS (confirmed COL3A mutation) presented to 3 different hospitals over a 5-year period, with possible inflammatory arthritis prior to the EDS diagnosis. Several studies have shown that a significant proportion of patients attending early arthritis clinics do not have inflammatory rheumatic diseases. In our experience, heritable disorders of connective tissue and hypermobility spectrum disorders are often overlooked and should be included in the differential diagnosis in patients seen in the early arthritis clinics.

Objectives:

We aimed to audit the outcome of patients who were seen in the early arthritis clinics focusing on those who were not found to have inflammatory rheumatic diseases and to explore if joint hypermobility was considered as a possible cause of patient’s symptoms.

Methods:

A retrospective analysis of medical records was conducted of patients attending the early arthritis clinics at University College London Hospital between May 2018 and December 2019.

Results:

279 patients (90 males, 189 females) were seen in the early arthritis clinics with a mean age of 48 (range 19-91). 131 patients (47%) did not have inflammatory rheumatic diseases. Sixty-three of these patients (48%) were not given any diagnosis and joint hypermobility was not assessed during the appointment. Eleven patients (8%) had features of hypermobility, 11 patients (8%) were diagnosed with fibromyalgia, 20 patients (15%) received a diagnosis of osteoarthritis, and 27 patients (21%) were given other diagnoses including tendonitis and soft tissue pathology.

Conclusion:

Almost 50 % of patients who were seen in the early arthritis clinics did not have inflammatory rheumatic diseases and 21 % of patients were discharged without a clear diagnosis. In these patients, hypermobility was not assessed and this is consistent with our observation. In our experience recognising joint hypermobility as a cause of arthralgia and intermittent joint swelling usually reassures patients and motivates them to follow appropriate treatment protocols including physiotherapy and occupational therapy thus allowing a more efficient utilization of early arthritis clinic resources towards those with true inflammatory rheumatic diseases. Going forward, we have planned to embed a cognisant attitude towards hypermobility within the relevant clinics to ensure that patients who do not have inflammatory arthritis are assessed for hypermobility and directed towards appropriate management.

References:

[1]Castori M, Hakim A. Contemporary approach to joint hypermobility & related disorders. Current Opinion in Pediatrics. 2017;29(6):640-649.

[2]Emma Connelly, Alan Hakim, Sally Davenportc & Jane Simmonds, A study exploring the prevalence of Joint Hypermobility Syndrome in patients attending a Musculoskeletal Triage Clinic. Physiotherapy Practice & Research 36 (2015) 43–53

[3]Feuchtenberger M, Nigg A, Kraus M, Schäfer A. Rate of Proven Rheumatic Diseases in a Large Collective of Referrals to an Outpatient Rheumatology Clinic under Routine Conditions. Clin Med Insights Arthritis Musculoskelet Disord. 2016; 9: 181–187.

Disclosure of Interests:

None declared

SAT0515 COMPLEX HYPERMOBILITY EHLERS-DANLOS SYNDROME (HEDS): MAPPING THE PATIENT’S JOURNEY OVER 40 MONTHS IN A TERTIARY REFERRAL CENTRE

Background:

Ehlers-Danlos Syndromes are heritable connective tissue disorders.They are multisystemic and patients can present with several symptoms such as joint pain and instability, visceral and autonomic dysfunction, as well as significant psychosocial sequela. Managing this cohort of young patients is usually challenging as many patients present late due to delayed diagnosis, often with several complications, problems with mobility and opioid use. Furthermore, there is often a prolonged lack of coordinated healthcare and access to social care services. A recent parliamentary debate in the U.K. highlighted that hEDS services are excluded from specialist Rheumatology commissioning services. In order to ascertain the relevance and utility of specialist services in this population, we conducted this study.

Objectives:

The objective of this study was to map the patient experience following a referral to the specialist clinic in order to assess the need for an integrated, multidisciplinary approach to treating patients with hypermobility EDS.

Methods:

We retrospectively reviewed the records of 50 patients with the diagnosis of hypermobility EDS who were seen in a specialist hypermobility clinic at University College Hospital UCLH between January 2016 and March 2016. Relevant data was collected regarding their medical care in our hospital up to October 2019.

Results:

The median age was 37 (range 21-59). We had 10 males and 40 females. The diagnosis of hypermobility EDS was based on the 1997 criteria as these patients were seen prior to the 2017 classification. Overall, the study yielded 6 key themes: 1. All patients experienced chronic pain, with 36% reporting use of opioids for pain management. 2. Patients were referred to multiple medical specialities within the same hospital trust, (22% patients were referred to ≥5 specialities). 3. Patients required a high number of follow up appointments (28% of patients required ≥20 follow-up visits). 4. Failed discharges were common; patients were often referred back to the Rheumatology Clinic despite being discharged to primary care. 5. Patients had a significant number of comorbidities, reflected by polypharmacy. (36% of patients were prescribed ≥5 medications). 6. Disability was high (20% of patients reported severe mobility problems).

Conclusion:

This study shows that patients with hEDS referred to UCLH have significant levels of disability, opioids use and polypharmacy especially for a relatively young population of patients. They need a complex interdisciplinary approach in a timely manner. In order to minimise delays and allow earlier diagnosis and intervention, we have recently adopted a multidisciplinary team approach, including pain specialists, rheumatologists, psychologists, physiotherapists, nurse specialists, urogynaecologists and neurogastroenterologists. This allows more coordinated and efficient care and incorporates an EDS-specific pain management programme. Specialised services for complex hEDS cases should be established and adequately resourced. Moreover, it would be cost effective to commission a patient-centred “one-stop-shop” service, where patients, who often travel from long distances with severe disabilities, can be seen by multiple specialities in a single visit.

References:

[1]Bennett, S., Walsh, N., Moss, T. and Palmer, S. (2019). Understanding the psychosocial impact of joint hypermobility syndrome and Ehlers–Danlos syndrome hypermobility type: a qualitative interview study. Disability and Rehabilitation, pp.1-10. Healthwatch Calderdale. (2019). Hypermobility Syndromes Project - Healthwatch Calderdale.

[2]Tinkle, B., Castori, M., Berglund, B., Cohen, H., Grahame, R., Kazkaz, H. and Levy, H. (2017). Hypermobile Ehlers-Danlos syndrome (a.k.a. Ehlers-Danlos syndrome Type III and Ehlers-Danlos syndrome hypermobility type): Clinical description and natural history. American Journal of Medical Genetics Part C: Seminars in Medical Genetics, 175(1), pp.48-69.

Disclosure of Interests:

None declared

Exploring the structure of Xe isotopes in A ~ 130 region: Single particle and collective excitations

High and medium spin structures of 130,131Xe have been studied using α-induced fusion-evaporation reaction and the Indian National Gamma Array (INGA) coupled with a digital data acquisition system. Various new band structures and near yrast levels of 131Xe have been established. The multipolarities of the observed transitions have been assigned on the basis of the DCO ratios and the polarization asymmetry measurements. Band structures based on 1-quasi-particle (qp), 3-qp configurations have been observed. A new Magnetic Rotational (MR) band based on 5-qp configuration has also been established in 131Xe. The MR band has been interpreted in terms of shears mechanism with principal axis cranking (SPAC) calculations. Shell Model calculations are carried out to describe the non yrast states of 131Xe above the 11/2− isomer. New excited states have also been identified in 130Xe, produced in the same reaction.

IVF outcome in azoospermic cancer survivors

OBJECTIVE

To assess clinical outcome among infertile couples treated by in vitro fertilization (IVF) and intra cytoplasmic sperm injection (ICSI) using testicular sperm from azoospermic cancer survivors.

STUDY DESIGN

This clinical retrospective study included infertile couples treated in a single tertiary referral center between 1996 and 2013. All male partners were cancer survivors who were diagnosed with azoospermia due to previous gonadotoxic treatments and referred to testicular sperm extraction (TESE). Retrieved sperm was used for IVF-ICSI among patients' spouses. Sperm retrieval rate and IVF-ICSI outcome were evaluated.

RESULTS

Sperm was successfully retrieved in 12 out of 36 patients (33.3%) on initial TESE, with an overall sperm retrieval rate of 38.6% (17 of 44). Female patients were 29.8±5.1 years old. The average number of retrieved oocytes was 14.0±4.0 per cycle, with clinical pregnancy and live birth rates per successful TESE of 64% (11 of 17) and 58.8% (10 of 17), respectively. Age, serum FSH, testicular volume and time from chemotherapy to TESE were not significantly different between patients with successful TESE to those without. Patients suffering from seminomas had significantly higher sperm retrieval rate, as compared to patients who had Hodgkin's lymphoma (P=0.024).

CONCLUSIONS

Post-chemotherapy azoospermia can be successfully treated with TESE and ICSI, and should be offered to azoospermic cancer survivors who did not cryopreserve sperm prior to their gonadotoxic treatments.

Abstract POSTER-BIOL-1307: Bioenergetic adaptations in chemoresistant ovarian cancer cells

While, normal cells primarily rely on mitochondrial oxidative phosporylation (OXPHOS), cancer cells are known to preferentially take up glucose to produce energy using aerobic glycolysis pathway, described as the ‘Warburg effect’. Recently, this view that all cancer cells are dependent on glycolysis is being challenged. We examined the bioenergetic characteristics of a panel of 10 human ovarian cancer cell lines and 2 immortalized ovarian surface epithelial cell lines, using the Seahorse XF Extracellular Flux analyzer to measure glycolysis and mitochondrial respiration in real time using the outputs of extracellular acidification rate (ECAR) and oxygen consumption rate (OCR) respectively. The mitochondrial bioenergetics was read by taking baseline OCR following sequential addition of oligomycin, FCCP and rotenone/antimycin, which inhibit mitochondrial ATP synthase, uncouple mitochondrial OXPHOS and induce maximal respiration respectively. Glycolytic profile (ECAR) was generated after keeping the cells glucose free followed by sequential addition of glucose to induce glycolysis, oligomycin and 2-deoxy glucose to inhibit glycolysis. The OCR profile showed ovarian cancer cells lines to have diverse mitochondrial bioenergetics and diverse ability to use glycolysis. The OCR:ECAR ratio showed varied bioenergetic organization, with some cells relying heavily on glycolysis or OXPHOS, but most using both pathways equally. A significant positive correlation (correlation coefficient 0.7705; p=0.003) was observed between mitochondrial respiration and glycolysis, confirming that glycolysis dependent cells have lower ATP-linked respiration rates. A similar diversity was observed in the mRNA expression of glycolytic (Glut1 and LDH) and mitochondrial (PGC-1α and CoxVb) genes. These findings highlight the actuality of extreme heterogeneity observed in cancer cells. A unique observation was the distinctive behavior of chemosensitive and resistant cell line pairs. Our panel contained a set of (i) cisplatin sensitive A2780 and resistant C200 cell lines and (ii) taxol sensitive PEO1 and resistant PEO4 cell lines. The resistant cells (C200 and PEO4) displayed higher ECAR and OCR profile compared to the sensitive cells (A2780 and PEO1), indicating an increased utilization of both energy pathways. The OCR:ECAR ratio suggested the sensitive cell lines to be glycolytic and the resistant cell lines to be highly metabolically active. This was further supported by increased mitochondrial function in the resistant cells, measured in terms of augmented fatty acid oxidation and mitochondrial potential in the resistant cells. On inhibition of glycolysis, the resistant cells were able to increase OX-PHOS and maintain their growth, whereas sensitive cells could not increase OX-PHOS and ceased growth. This led us to a novel hypothesis that chemo-resistant ovarian cancer cells exhibit greater plasticity than normal and sensitive cells, making them more adaptable to rearrange their metabolic phenotype according to microenvironment changes and stress, giving them a selective advantage to overcome adverse conditions. Thus, the metabolic diversity could be a means of selecting resilient chemo-resistant cells over a period of cytotoxic insults.

Citation Format: J. Chhina, S. Dar, M. Deshpande, S. Giri, A. Munkarah, R. Rattan. Bioenergetic adaptations in chemoresistant ovarian cancer cells [abstract]. In: Proceedings of the 10th Biennial Ovarian Cancer Research Symposium; Sep 8-9, 2014; Seattle, WA. Philadelphia (PA): AACR; Clin Cancer Res 2015;21(16 Suppl):Abstract nr POSTER-BIOL-1307.

Increased risk of preterm birth in singleton pregnancies after blastocyst versus Day 3 embryo transfer: Canadian ART Register (CARTR) analysis

STUDY QUESTION

Are the fetal outcomes of singleton pregnancies that result from cleavage stage embryo transfer (ET) different from the outcomes from Day 5/6 blastocyst stage ET?

SUMMARY ANSWER

There was a significantly higher risk of preterm birth (<37 weeks) in singletons after extended embryo culture (Day 5/6) compared with cleavage stage (Day 3) transfer.

WHAT IS KNOWN ALREADY

Two recent studies, from Sweden and the USA, reported an increased risk of preterm birth in singleton pregnancies after Day 5/6 ET compared with Day 3 ET. The US study also showed increased early preterm births and the Swedish study showed increased fetal malformations in this group.

STUDY DESIGN, SIZE AND DURATION

A retrospective cohort study was performed. Data were collected from the Canadian ART Register database for all singleton births after fresh IVF/ICSI ET cycles (2001-2009).

PARTICIPANTS/MATERIALS, SETTING, METHODS

A total of 12 712 singleton births were included. Of these, 9506 resulted from a Day 3 ET and 3206 resulted from a blastocyst (Day 5/6) ET.

MAIN RESULTS AND THE ROLE OF CHANCE

Preterm birth rate <37 weeks (unadjusted by potential confounding factors) was higher with Day 5/6 versus Day 3 transfers (17.2 versus 14.1%, P < 0.001). Using logistic regression analysis to adjust for confounding factors, preterm birth rate <37 weeks was the only outcome significantly increased after Day 5/6 compared with Day 3 transfer (odds ratio 1.32, 95% confidence interval 1.17-1.49). The following confounding factors were adjusted for: year of treatment (2001-2009), maternal age (continuous), parity (0 versus ≥1 birth), diagnosis category, number of oocytes retrieved [≤20 versus >20 (high responder group)], insemination method (IVF versus ICSI), number of embryos transferred (1, 2 or ≥3) and the presence of a vanishing twin (≥1 fetal heart on the initial ultrasonographic examination).

LIMITATIONS, REASONS FOR CAUTION

Post-natal follow-up studies will be required to determine if this difference we observed translates into adverse long-term effects on these offspring. The rate of early preterm births (<32 weeks) was higher in Day 5/6 versus Day 3, but the low number of cases in this category did not have the power to show a difference (3.0 versus 2.7%, P = 0.34).

WIDER IMPLICATIONS OF THE FINDINGS

We found a significantly higher risk of preterm birth (<37 weeks) in singletons after extended embryo culture (Day 5/6) compared with cleavage stage (Day 3) transfer, even when adjusting for confounding factors. Our findings are in agreement with the previous two studies; however, we did not show a difference in the very preterm deliveries (unlike the US study) or in fetal malformations (as in the Swedish study). We hypothesize that there may be a deleterious effect of prolonged in vitro embryo culture on subsequent placentation. Longer term follow-up studies will be required to determine if prolonged in vitro culture to the blastocyst stage has an adverse effect on the long-term health of offspring when compared with shorter cleavage stage culture.

STUDY FUNDING/COMPETING INTEREST(S)

None.

The clinical and biological effects of thalidomide in patients with myelodysplastic syndromes

Thirty patients with myelodysplastic syndromes (MDS) were treated with thalidomide at 100 mg/d p.o., increased as tolerated to 400 mg/d for 12 weeks. Levels of apoptosis, macrophage number, microvessel density (MVD), tumour necrosis factor alpha (TNF-alpha), transforming growth factor beta (TGF-beta), interleukin 6 (IL-6), vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) were determined in the serum, bone marrow (BM) plasma and BM biopsies before and after therapy. Pretherapy biological characteristics of MDS patients were compared with similar studies performed in 11 normal volunteers. Ten patients demonstrated haematological improvement in the erythroid series, six becoming transfusion independent. Responders had a higher pretherapy platelet count (P < 0.048) and lower BM blasts (P < 0.013). Median time to response was 10 weeks, and four remain in remission beyond a year. Pretherapy MDS BMs showed higher MVD (P < 0.001) and TGF-beta (P < 0.03) and higher serum TNF-alpha (P < 0.008) compared with normal control subjects. After therapy, only BM TGF-beta decreased significantly (P < 0.002). Pretherapy haemoglobin was directly related to serum VEGF (P < 0.001) in responders and inversely related in non-responders (P < 0.05), suggesting the possibility that angiogenesis may be a primary pathology in the former and a consequence of anaemia-induced hypoxia in the latter. We conclude that thalidomide has important clinical and biological effects in at least a subset of MDS patients, but the precise mechanism of its action remains unknown and requires further study including a larger number of patients.

Thalidomide produces transfusion independence in long-standing refractory anemias of patients with myelodysplastic syndromes

Thalidomide was administered to 83 patients with myelodysplastic syndrome (MDS), starting at 100 mg by mouth daily and increasing to 400 mg as tolerated. Thirty-two patients stopped therapy before 12 weeks (minimum period for response evaluation), and 51 completed 12 weeks of therapy. International Working Group response criteria for MDS were used to evaluate responses. Intent-to-treat (ITT) analysis classified all off-study patients as nonresponders. Off-study patients belonged to a higher risk category (P =.002) and had a higher percentage of blasts in their pretherapy bone marrow than patients who completed 12 weeks of therapy (P =.003). No cytogenetic or complete responses were seen, but 16 patients showed hematologic improvement, with 10 previously transfusion-dependent patients becoming transfusion independent. Responders had lower pretherapy blasts (P =.016), a lower duration of pretherapy platelet transfusions (P =.013), and higher pretherapy platelets (P =.003). Among responders, 9 had refractory anemia (RA); 5 had RA with ringed sideroblasts; and 2 had RA with excess blasts. By ITT analysis, 19% of patients (16 of 83) responded, and when only evaluable patients were analyzed, 31% (16 of 51) responded. It was concluded that thalidomide, as a single agent, is effective in improving cytopenias of some MDS patients, especially those who present without excess blasts. (Blood. 2001;98:958-965)

Patients with myelodysplastic syndromes benefit from palliative therapy with amifostine, pentoxifylline, and ciprofloxacin with or without dexamethasone

Thirty-five patients with myelodysplastic syndrome (MDS) were registered on protocol MDS 96-02 and were receiving continuous therapy with pentoxifylline 800 mg 3 times a day and ciprofloxacin 500 mg twice a day by mouth; dexamethasone was added to the regimen for the partial responders and the nonresponders after 12 weeks at a dose of 4 mg by mouth every morning for 4 weeks. Amifostine was administered intravenously 3 times a week at 3 dose levels (200 mg/M(2), 300 mg/M(2), and 400 mg/M(2)) to cohorts of 10 patients each. Therapy has been continued for 1 year in responders. Twenty-nine have completed at least 12 weeks of therapy and are available for response evaluation. Of the 21 men and 8 women (median age, 67 years), 20 had refractory anemia (RA), 3 had RA with ringed sideroblasts (RARS), 5 had RA with excess blasts (RAEB), and 1 had chronic myelomonocytic leukemia (CMMoL). Five had secondary MDS. No differences were noted in response rates among the 3 dose levels. Seven patients did not respond at all, and 22 showed an improvement in cytopenias (76%). Three had a triple lineage response, 10 had a double lineage response, and 9 had a single lineage response (8 of 9 in absolute neutrophil count [ANC] and 1 had more than a 50% reduction in packed red blood cell transfusions). Fifteen patients responded only after the addition of dexamethasone, whereas 7 responded before. When examined by lineage, 19 of 22 showed improved ANC, 11 of 22 demonstrated more than 50% reduction in blood transfusions, improved Hb levels, or both, and 7 of 22 showed improvement in platelet counts. Interestingly, the responses were frequently slow to appear, and continued improvement in counts was seen up to 12 months of therapy and beyond. This study supports the feasibility of treating patients with MDS with the unique approach of cytoprotection and anticytokine therapies as well as the principle that prolonged commitment to treatment is desirable when noncytotoxic agents are administered. (Blood. 2000;95:1580-1587)

Sequential activation of caspase-1 and caspase-3-like proteases during apoptosis in myelodysplastic syndromes

Myelodysplastic syndromes (MDS) are a group of hematopoietic disorders characterized by the concomitant presence of peripheral cytopenias and normocellular to hypercellular BM. This paradox has been proposed to be due to the presence of excessive proliferation matched by excessive intramedullary apoptosis of hematopoietic cells. When cultured in vitro MDS BM mononuclear cells (BMMC) undergo apoptosis within 4 h. We measured caspase-1-like and caspase-3-like activity in 22 MDS and 4 normal BM immediately following cell separation or after 4 h culture. When cultured in vitro, MDS BMMC demonstrated an increased apoptotic index within 4 h as measured by in situ end-labeling of fragmented DNA that was matched by a concurrent increase in caspase-3-like specific activity, and the two were significantly correlated. During the 4 h culture, a sequential activation of caspase-1-like and caspase-3-like activities was detected. Caspase-1-like specific activity was detected early and transiently at approximately 15 min, followed by a gradual increase in caspase-3-like-specific activity peaking at 2 h. When the broad-spectrum caspase inhibitor, Z-VAD.FMK, was included in the MDS BM aspirate 4 h culture, apoptosis was attenuated. We conclude that sequential activation of caspase-1-like and caspase-3-like activities may form the central biochemical pathway of apoptosis in BMMC from some MDS patients, and prevention of this process by caspase inhibitors may be of significant therapeutic value for these patients, in whom supportive care continues to be the mainstay of therapy.

Biologic characteristics of patients with hypocellular myelodysplastic syndromes

Rates of proliferation and apoptosis as well as expression of tumor necrosis factor alpha (TNF-alpha), transforming growth factor beta (TGF-beta) and the number of macrophages were measured in bone marrow (BM) biopsies of 33 patients who presented with hypocellular (cellularity < 30%) myelodysplastic syndromes (MDS). Results showed that 2/3 of the patients had high apoptosis, high cytokine levels and large number of macrophages in their biopsies while 1/3 did not. Apoptosis and TNF-alpha levels were directly related (r = 0.583, P = 0.003, n = 24) as was apoptosis and the degree of anemia (P = 0.033, n = 18). A subgroup of patients with abnormalities of chromosomes 5 or 7 had higher platelets (P = 0.026) and higher apoptosis (P = 0.038) when compared with the rest of the group. Eight patients had no evidence of apoptosis and almost no detectable TNF-alpha in their biopsies. We conclude that within the hypocellular variant of MDS, there may be two distinct sub-groups of patients, one who present with high cytokine-mediated intramedullary apoptosis and the other who may be better characterized as having a stem-cell failure defect since they showed no evidence of apoptosis.

Biologic characteristics of 164 patients with myelodysplastic syndromes

Rates of proliferation, apoptosis and cytokine expression were measured in bone marrow (BM) biopsies of 164 myelodysplastic syndrome (MDS) patients. There were 107 males and 57 females. Median age was 69 years and 101 had refractory anemia (RA), 17 RA with ringed sideroblasts (RARS), 38 with RA and excess blasts (RAEB) and 8 with RAEB in transformation (RAEB-t). Apoptosis measured by in-situ end labeling (ISEL) was directly related to the number of macrophages (p = 0.028, n = 83). Mean tumor necrosis factor alpha (TNF-alpha) and ISEL positivity were higher in RAEB + RAEB-t patients (p = 0.0554 and p = 0.06 respectively) while hemoglobin was higher for RA + RARS group (p = 0.0472). Patients with high apoptosis had lower white blood cell counts (p = 0.0009), lower percentage of blasts (p = 0.0009) and higher number of macrophages (p = 0.0086). We conclude that measurements of apoptosis, proliferation and cytokine expression provide important biological information which helps to distinguish RA + RARS patients from RAEB + RAEB-t patients, and may be of additive prognostic significance.

Biological characteristics of myelodysplastic syndrome patients who demonstrated high versus no intramedullary apoptosis

Spontaneous intramedullary apoptosis was measured in bone marrow (BM) biopsies of 175 patients with myelodysplastic syndromes (MDS) using in situ end-labeling (ISEL) of fragmented DNA. Two groups of high (n=71) versus low (n =43) levels of apoptosis were identified while 61 patients were ISEL-negative. Semiquantitative assessment of 3 cytokines, the number of macrophages and in vivo labeling indices (LI) were also determined from consecutive sections of the biopsy. Patients with high apoptosis levels tended to have a high LI (p=0.013), more macrophages in their BM biopsies (p=0.006) and higher tumor necrosis factor alpha (TNF-alpha) levels (not significant) compared to patients with no apoptosis. In addition, low risk MDS patients had significantly lower rates of apoptosis (p = 0.047) and lower levels of TNF-alpha (p = 0.055) compared to high-risk MDS patients. We conclude that the genesis of cytopenias in MDS is of multifactorial origin and that cytokine-associated apoptosis clearly identifies a distinct biological subgroup of patients who may benefit selectively by use of anti-cytokine therapies.

Tumor necrosis factor-alpha levels decrease with anticytokine therapy in patients with myelodysplastic syndromes

Tumor necrosis factor-alpha (TNF-alpha) levels were measured in the serum (sTNF-alpha) or bone marrow (BM) biopsies of 43 patients with myelodysplastic syndromes (MDS) who subsequently received therapy with a combination of pentoxifylline and ciprofloxacin (PC) with or without dexamethasone (PCD). All 43 patients received only PC therapy for 12 weeks, after which 18 of 36 nonresponders received PCD. A total of 18 of 43 patients showed a hematologic or cytogenetic response or both. BM TNF-alpha levels were semiquantitatively assessed using immunohistochemistry on a scale of 0-8+ and in the serum using enzyme linked immunoassay. The median TNF-alpha for the entire group was 3.0 in BM and 6.9 pg/ml in the serum, and 14 patients had no detectable levels. Responders had higher BM levels (median 3.5 vs. 2.0) than nonresponders, although this was not statistically significant. During PC therapy, a decline in BM TNF-alpha level was seen in the entire group, which was significant at 2 weeks (p = 0.02), 8 weeks (p = 0.001), and 12 weeks (p = 0.0001). Both responders (p = 0.01) and nonresponders (p = 0.03) had a decline at 8 weeks, but at 12 weeks, only the responders continued to show a significant decline (p = 0.03). We conclude that MDS patients with high BM TNF-alpa levels have a better chance of responding to PCD therapy and that the therapy is quite successful in reducing the TNF-alpha levels in a sustained fashion. Future studies need to be directed at identifying agents that would be more potent suppressors of the proapoptotic cytokines in these patients.

Effect of fatiguing exercise on longitudinal bone strain as related to stress fracture in humans

Muscular fatigue in the training athlete or military recruit has been hypothesized to cause increased bone strain that may contribute to the development of a stress fracture. Under normal circumstances, muscles exert a protective effect by contracting to reduce bending strains on cortical bone surfaces. In vivo strain studies in dogs show that muscle fatigue following strenuous exercise elevates bone strain and changes strain distribution. However, a similar experiment has yet to be performed in humans. The purpose of this work was to test the hypothesis in humans that strenuous fatiguing exercise causes an elevation in bone strain. It was also hypothesized that this elevation is greater in younger people than in older people due to the decline in muscle strength and endurance that normally occurs with age. To test these hypotheses, strain in the tibiae of seven human volunteers was measured during walking before and after a period of fatiguing exercise. Neither hypothesis was sustained. Post-hoc analysis of the strain data suggests that strain rate increases after fatigue with a greater increase in younger as opposed to older persons. Although not conclusive, this suggests that it is strain rate, rather than strain magnitude, that may be causal for stress fracture.

Jejunal adenocarcinoma presenting as iron deficiency in a young man

A 30-year-old man presented with iron deficiency anemia and occult blood in his stools. Both upper and lower gastrointestinal tract endoscopy were initially unrevealing. This case illustrates the importance of small bowel follow through/enteroclysis supplemented by endoscopic examination and biopsy for adenocarcinoma of the proximal jejunum.

Measurement of apoptosis, proliferation and three cytokines in 46 patients with myelodysplastic syndromes

Extensive apoptosis or programmed cell death (PCD) of both hematopoietic (erythroid, myeloid, megakaryocytic) and stromal cells in myelodysplastic syndromes (MDS) cancels the high birth-rate resulting in ineffective hematopoiesis and has been demonstrated as the probable basis for peripheral cytopenias in MDS by our group. It is proposed that factors present in the microenvironment are inducing apoptosis in all the cells whether stromal or parenchymal. To investigate this hypothesis further, bone marrow biopsies from 46 MDS patients and eight normal individuals were examined for the presence of three cytokines, tumor necrosis factor-alpha (TNF-alpha), transforming growth factor-beta (TGF-beta) and granulocyte macrophage-colony stimulating factor (GM-CSF) and one cellular component, macrophages, by the use of monoclonal antibodies immunohistochemically. Results showed the presence of TNF-alpha and TGF-beta in 41/46 and 40/46 cases of MDS respectively, while only 15 cases showed the presence of GM-CSF. Further a significant direct relationship was found between the degree of TNF-alpha and the incidence of PCD (p= 0.0015). Patients who showed high PCD also had an elevated TNF-alpha level. Thus, the expression of high amounts of TNF-alpha and TGF-beta and low amounts of the viability factor GM-CSF may be responsible for the high incidence of PCD leading to ineffective hematopoiesis in MDS. Future studies will be directed at attempting to reverse the lesion in MDS by using anti-TNF-alpha drugs such as pentoxifylline.

A paradigm shift in myelodysplastic syndromes

A poorly defined transforming event(s) affects the pluripotential bone marrow (BM) stem cell in myelodysplastic syndromes (MDS), conferring a growth advantage upon it which leads eventually to monoclonal hematopoiesis. The progeny of this transformed ancestor undergo recognizable albeit dysplastic maturation. We propose that this picture is further complicated by a variety of cytokines, tumor necrosis factor alpha (TNF-alpha), transforming growth factor beta (TGF-beta) and interleukin 1beta (IL-1beta) which exert a dual effect on the diseased cells. The immature CD34+ cells are stimulated to proliferate, while their later differentiated daughters are induced to undergo apoptosis accounting for the clinical syndrome of pancytopenia despite hypercellular BMs. Studies directed at measuring the rates of proliferation and apoptosis as well as the levels of TNF-alpha, TGF-beta and IL-1beta confirm this hypothesis and are presented in greater detail. A novel approach towards MDS therapy emerges as a result of this paradigm shift based upon the premise that anti-cytokine therapy would prevent excessive intramedullary apoptosis and result in improved cytopenias as well as cause a slowing down of the diseased precursor cell proliferation resulting in resumption of polyclonal hematopoiesis. Because a number of cytokines function through common lipid second messengers, interruption of this pathway should theoretically cause disruption in the signalling of a cascade of cytokines.

Novel insights into the biology of myelodysplastic syndromes: excessive apoptosis and the role of cytokines

The paradox of myelodysplastic syndromes (MDS) which present with pancytopenias despite cellular bone marrows (BM) was investigated by conducting detailed studies of proliferation and apoptosis in 89 MDS patients. Our results demonstrated a rapid rate of both proliferation as well as apoptosis. Levels of three cytokines, tumor necrosis factor-alpha (TNF-alpha), transforming growth factor-beta (TGF-beta) and interleukin-1 beta (IL-1 beta) were measured in the same patients. High levels of TNF-alpha were found to correlate with high levels of apoptosis in 83 MDS patients (P = 0.0045). We propose a dual role for TNF-alpha (or other cytokines) in the pathogenesis of MDS. On the one hand, TNF-alpha induces apoptosis in the maturing cells causing pancytopenia while on the other, it stimulates the proliferation of the primitive progenitors accounting for the hypercellular BM frequently seen in MDS. A new model for MDS is presented. The initial abnormality probably affects a primitive hemopoietic progenitor which acquires a growth advantage leading to monoclonal hemopoiesis, which in turn makes these cells susceptible towards acquiring additional mutations and appearance of cytogenetically marked (or unmarked) clones. Cytokines such as TNF-alpha whose source is presently unknown, then contribute towards the clinical syndrome of pancytopenia and hypercellularity.

A comparative study of risk factors for acute myocardial infarction amongst men of Indo-origin in Trinidad and the UK

A high cardiovascular mortality rate exists amongst people of Indo-origin in Trinidad (third generation migrants) and the United Kingdom (first generation migrants). To investigate the differences in cardiovascular risk factors in these two populations, we surveyed all male patients of Indo-origin with acute myocardial infarction, admitted over a similar 8-week period to the Coronary Care Units of a district general hospital in Birmingham, United Kingdom and a similar hospital in San Fernando, Trinidad. Nineteen patients (mean age 62.2 years +/- S.D. 2.58) were admitted to the Birmingham hospital (UK Group) and fifty-five (mean age 58.1 years +/- S.D. 1.44) to the San Fernando hospital (Trinidad Group). There was no age difference between the groups (P = 0.18). There was a significantly greater proportion of smokers in the Trinidad group (70.9% vs. 63.2%, chi 2 = 4.56, P = 0.03), which also had a higher proportion of diabetics (36.4% vs. 31.6%) and hypertensives (34.5% vs. 31.6%). Mean systolic and diastolic blood pressures were higher in hypertensives from the Trinidad group (Trinidad group 146.6 mmHg +/- 16.9/93.4 mmHg +/- 11.4 vs. UK group 120.8 mmHg +/- 25.4/75.0 mmHg +/- 13.4; P < 0.05). The mean waist to hip ratio was greater in the Trinidad group (1.01 +/- S.D. 0.06) when compared to the UK group (0.95 +/- S.D. 0.05) (paired t-test, P < 0.01). Only six Trinidadian males performed regular exercise and only four of the UK group did so.(ABSTRACT TRUNCATED AT 250 WORDS)