Variables associated with nonresponders to high-frequency (10 kHz) spinal cord stimulation

INTRODUCTION

The use of spinal cord stimulation (SCS) therapy to treat chronic pain continues to rise. Optimal patient selection remains one of the most important factors for SCS success. However, despite increased utilization and the existence of general indications, predicting which patients will benefit from neuromodulation remains one of the main challenges for this therapy. Therefore, this study aims to identify the variables that may correlate with nonresponders to high-frequency (10 kHz) SCS to distinguish the subset of patients less likely to benefit from this intervention.

MATERIALS AND METHODS

This was a retrospective single-center observational study of patients who underwent 10 kHz SCS implant. Patients were divided into nonresponders and responders groups. Demographic data and clinical outcomes were collected at baseline and statistical analysis was performed for all continuous and categorical variables between the two groups to calculate statistically significant differences.

RESULTS

The study population comprised of 237 patients, of which 67.51% were responders and 32.49% were nonresponders. There was a statistically significant difference of high levels of kinesiophobia, high self-perceived disability, greater pain intensity, and clinically relevant pain catastrophizing at baseline in the nonresponders compared to the responders. A few variables deemed potentially relevant, such as age, gender, history of spinal surgery, diabetes, alcohol use, tobacco use, psychiatric illness, and opioid utilization at baseline were not statistically significant.

CONCLUSION

Our study is the first in the neuromodulation literature to raise awareness to the association of high levels of kinesiophobia preoperatively in nonresponders to 10 kHz SCS therapy. We also found statistically significant differences with greater pain intensity, higher self-perceived disability, and clinically relevant pain catastrophizing at baseline in the nonresponders relative to responders. It may be appropriate to screen for these factors preoperatively to identify patients who are less likely to respond to SCS. If these modifiable risk factors are present, it might be prudent to consider a pre-rehabilitation program with pain neuroscience education to address these factors prior to SCS therapy, to enhance successful outcomes in neuromodulation.

Healthcare Utilization (HCU) Reduction with High-Frequency (10 kHz) Spinal Cord Stimulation (SCS) Therapy

Spinal cord stimulation (SCS) is a well-established treatment for patients with chronic pain. With increasing healthcare costs, it is important to determine the benefits of SCS in healthcare utilization (HCU). This retrospective, single-center observational study involved 160 subjects who underwent implantation of a high-frequency (10 kHz) SCS device. We focused on assessing trends in HCU by measuring opioid consumption in morphine milligram equivalents (MME), as well as monitoring emergency department (ED) and office visits for interventional pain procedures during the 12-month period preceding and following the SCS implant. Our results revealed a statistically significant reduction in HCU in all domains assessed. The mean MME was 51.05 and 26.52 pre- and post-implant, respectively. There was a 24.53 MME overall decrease and a mean of 78.2% statistically significant dose reduction (p < 0.0001). Of these, 91.5% reached a minimally clinically important difference (MCID) in opioid reduction. Similarly, we found a statistically significant (p < 0.01) decrease in ED visits, with a mean of 0.12 pre- and 0.03 post-implant, and a decrease in office visits for interventional pain procedures from a 1.39 pre- to 0.28 post-10 kHz SCS implant, representing a 1.11 statistically significant (p < 0.0001) mean reduction. Our study reports the largest cohort of real-world data published to date analyzing HCU trends with 10 kHz SCS for multiple pain etiologies. Furthermore, this is the first and only study evaluating HCU trends with 10 kHz SCS by assessing opioid use, ED visits, and outpatient visits for interventional pain procedures collectively. Preceding studies have individually investigated these outcomes, consistently yielding positive results comparable to our findings.

Treatment of Refractory Low Back Pain Using Passive Recharge Burst in Patients Without Options for Corrective Surgery: Findings and Results From the DISTINCT Study, a Prospective Randomized Multicenter Controlled Trial

OBJECTIVE

Spinal cord stimulation (SCS) is effective for relieving chronic intractable pain conditions. The Dorsal spInal cord STImulatioN vs mediCal management for the Treatment of low back pain study evaluates the effectiveness of SCS compared with conventional medical management (CMM) in the treatment of chronic low back pain in patients who had not undergone and were not candidates for lumbar spine surgery.

METHODS AND MATERIALS

Patients were randomized to passive recharge burst therapy (n = 162) or CMM (n = 107). They reported severe pain and disability for more than a decade and had failed a multitude of therapies. Common diagnoses included degenerative disc disease, spondylosis, stenosis, and scoliosis-yet not to a degree amenable to surgery. The six-month primary end point compared responder rates, defined by a 50% reduction in pain. Hierarchical analyses of seven secondary end points were performed in the following order: composite responder rate (numerical rating scale [NRS] or Oswestry Disability Index [ODI]), NRS, ODI, Pain Catastrophizing Scale responder rate, Patient Global Impression of Change (PGIC) responder rate, and Patient-Reported Outcome Measure Information System-29 in pain interference and physical function.

RESULTS

Intention-to-treat analysis showed a significant difference in pain responders on NRS between SCS (72.6%) and CMM (7.1%) arms (p < 0.0001). Of note, 85.2% of those who received six months of therapy responded on NRS compared with 6.2% of those with CMM (p < 0.0001). All secondary end points indicated the superiority of burst therapy over CMM. A composite measure on function or pain relief showed 91% of subjects with SCS improved, compared with 16% of subjects with CMM. A substantial improvement of 30 points was observed on ODI compared with a

CONCLUSIONS

This study found substantial improvement at six months in back pain, back pain-related disability, pain-related emotional suffering, PGIC, pain interference, and physical function in a population with severe, debilitating back pain for more than a decade. These improvements were reported in conjunction with reduced opioid use, injection, and ablation therapy.

CLINICAL TRIAL REGISTRATION

The Clinicaltrials.gov registration number for the study is NCT04479787.

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Key Words

• composite outcomes
• persistent spinal pain syndrome
• refractory chronic low back pain
• spinal cord stimulation

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MESH Headings

• Humans
• Low Back Pain/therapy
• Low Back Pain/psychology
• Treatment Outcome
• Prospective Studies
• Back Pain
• Spinal Cord Stimulation/methods
• Chronic Pain/diagnosis
• Chronic Pain/therapy

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Grants

• K08 CA228039 NCI NIH HHS

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Affiliation(s)

Timothy Deer The Spine and Nerve Center of the Virginias, Charleston, WV, USA
Christopher Gilligan Brigham & Women's Hospital, Boston, MA, USA
Steven Falowski Center for Interventional Pain & Spine, Lancaster, PA, USA
Mehul Desai International Spine, Pain & Performance Center, Washington, DC, USA
Julie Pilitsis Florida Atlantic University, FL, USA
Jessica Jameson Axis Spine Center, ID, USA
Susan Moeschler Mayo Clinic, Rochester, NY, USA
Robert Heros Spinal Diagnostics, OR, USA
Edward Tavel Clinical Trials of South Carolina, Charleston, SC, USA
Anne Christopher Saint Louis Pain Consultants, Chesterfield, MO, USA
Denis Patterson Nevada Advanced Pain Specialists, Reno, NV, USA
Sayed Wahezi Montefiore Medical Center-Waters Place, New York, NY, USA
Jacqueline Weisbein Napa Valley Orthopedic Medical Group, Napa, CA, USA
Ajay Antony The Orthopaedic Institute, FL, USA
Robert Funk Indiana Spine Group, IN, USA
Mohab Ibrahim Banner University Medical Center Tucson Campus, Tucson, AZ, USA
Chi Lim Carolina Orthopaedic & Neurosurgical Associates, SC, USA
Derron Wilson Goodman Campbell Brain & Spine, IN, USA
Michael Fishell Advanced Pain Care, NV, USA
Keith Scarfo Rhode Island Hospital, Providence, RI, USA
David Dickerson Northshore University HealthSystem, Chicago, IL, USA
Edward Braun Kansas University Medical Center, KS, USA
Patrick Buchanan Spanish Hills Interventional Pain Specialists, Camarillo, CA, USA
Robert M Levy Anesthesia Pain Care Consultants-Tamarac
Nathan Miller Coastal Pain & Spinal Diagnostics Medical Group, Carlsbad, CA, USA
Jonathan Duncan Burkhart Research Institute for Orthopaedics, San Antonio, TX, USA
Jijun Xu The Cleveland Clinic Foundation, OH, USA
Kenneth Candido Chicago Anesthesia Associates, SC, Chicago, IL, USA
Scott Kreiner Barrow Brain & Spine-Ahwatukee, Phoenix, AZ, USA
Marie E Fahey Abbott Labs, Austin, TX, USA
James Yue Connecticut Orthopaedics, CT, USA

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Tolerance and microbiological efficacy of cefepime or piperacillin/tazobactam in combination with vancomycin as empirical antimicrobial therapy of prosthetic joint infection: a propensity-matched cohort study

BACKGROUND

The use of piperacillin/tazobactam with vancomycin as empirical antimicrobial therapy (EAT) for prosthetic joint infection (PJI) has been associated with an increased risk of acute kidney injury (AKI), leading us to propose cefepime as an alternative since 2017 in our reference centre.

OBJECTIVES

To compare microbiological efficacy and tolerance of these two EAT strategies.

METHODS

All adult patients with PJI empirically treated with vancomycin+cefepime (n = 89) were enrolled in a prospective observational study and matched with vancomycin+piperacillin/tazobactam-treated historical controls (n = 89) according to a propensity score including age, baseline renal function and concomitant use of other nephrotoxic agents. The two groups were compared using Kaplan-Meier curve analysis, and non-parametric tests regarding the proportion of efficacious empirical regimen and the incidence of empirical therapy-related adverse events (AE).

RESULTS

Among 146 (82.0%) documented infections, the EAT was considered efficacious in 77 (98.7%) and 65 (98.5%) of the piperacillin/tazobactam- and cefepime-treated patients, respectively (P = 1.000). The rate of AE, particularly AKI, was significantly higher in the vancomycin+piperacillin/tazobactam group [n = 27 (30.3%) for all AE and 23 (25.8%) for AKI] compared with the vancomycin+cefepime [n = 13 (14.6%) and 6 (6.7%)] group (P = 0.019 and <0.001, respectively), leading to premature EAT discontinuation in 20 (22.5%) and 5 (5.6%) patients (P = 0.002). The two groups were not significantly different regarding their comorbidities, and AKI incidence was not related to vancomycin plasma overexposure.

CONCLUSIONS

Based on the susceptibility profile of bacterial isolates from included patients, microbiological efficacy of both strategies was expected to be similar, but vancomycin + cefepime was associated with a significantly lower incidence of AKI.

Antitumor necrosis factor alpha and an epidural abscess during a spinal cord stimulator trial: A case report

Spinal cord stimulation (SCS) is commonly utilized for treatment and management of chronic intractable low back and lower extremity pain. Although SCS is an overall low-risk procedure, there are potential life-threatening complications, including surgical site infections, such as an epidural abscess. Immunosuppression, a risk factor for epidural abscess, is becoming more common as an increasing number of patients are being treated with biologics for a multitude of autoimmune disorders. One class of commonly utilized biologics is antitumor necrosis factor (anti-TNF) alpha. Whereas these drugs can provide tremendous benefit for treatment and management of autoimmune disorders, there is no clear understanding of the degree to which these medications increase a patient's risk for surgical site infection, including those associated with SCS-related procedures. We present a case of an epidural abscess that developed immediately following an SCS trial in a patient with multiple undisclosed risk factors, including the use of an anti-TNF alpha agent to treat ankylosing spondylitis. For an epidural abscess, early diagnosis is key to preventing devastating complications and the need for surgical intervention. Immunosuppression can be the result of multiple issues including cancer, HIV, and biologic agents, such as anti-TNF alpha for the management of autoimmune diseases. There is limited evidence pertaining to the development of epidural abscesses in patients on anti-TNF alpha medications who undergo SCS. Studies focused on infections in patients undergoing SCS trials and permanent implants while on anti-TNF alpha agents could provide recommendations and guidance.

The mitochondrial genome of Apis mellifera simensis (Hymenoptera: Apidae), an Ethiopian honey bee

The complete mitochondrial genome of Apis mellifera simensis was 16,523 bp long. The 13 protein-coding genes, two rRNAs, and 22 tRNAs resembled other Apis mitogenomes. The location of this Apis subspecies in our phylogenetic tree supported the hypothesis that this subspecies is distinct, and is most closely related to A. m. scutellata and A. m. monticola.

The complete mitochondrial genome of the West African honey bee Apis mellifera adansonii (Insecta: Hymenoptera: Apidae)

The complete mitochondrial genome of the West African honey bee Apis mellifera adansonii consisted of 13 protein-coding genes, 22 transfer RNA genes, two ribosomal RNA genes, and a control region. It was 16,466 bp and consisted of 84.7% AT nucleotides. This subspecies had a similar mitogenome to those of other southern African honey bees, namely A. m. scutellata, A. m. capensis, and A. m. monticola.

The mitochondrial genome of the Spanish honey bee, Apis mellifera iberiensis (Insecta: Hymenoptera: Apidae), from Portugal

The Spanish honey bee Apis mellifera iberiensis, had a mitochondrial genome of 16,560 bp. It consisted of 13 protein-coding genes, 22 tRNA genes, two rRNA genes, and an AT-rich control region. The sample was from Portugal and its mitogenome resembled those of the African (A)-lineage honey bee subspecies. It was most closely related to other North African honey bees, namely A. m. sahariensis and A. m. intermissa.

The MAPK Kinase Kinase GmMEKK1 Regulates Cell Death and Defense Responses

MAPK signaling pathways play critical roles in plant immunity. Here, we silenced multiple genes encoding MAPKs using virus-induced gene silencing mediated by Bean pod mottle virus to identify MAPK genes involved in soybean (Glycine max) immunity. Surprisingly, a strong hypersensitive response (HR) cell death was observed when soybean MAPK KINASE KINASE1 (GmMEKK1), a homolog of Arabidopsis (Arabidopsis thaliana) MEKK1, was silenced. The HR was accompanied by the overaccumulation of defense signaling molecules, salicylic acid (SA) and hydrogen peroxide. Genes involved in primary metabolism, translation/transcription, photosynthesis, and growth/development were down-regulated in GmMEKK1-silenced plants, while the expression of defense-related genes was activated. Accordingly, GmMEKK1-silenced plants were more resistant to downy mildew (Peronospora manshurica) and Soybean mosaic virus compared with control plants. Silencing GmMEKK1 reduced the activation of GmMPK6 but enhanced the activation of GmMPK3 in response to flg22 peptide. Unlike Arabidopsis MPK4, GmMPK4 was not activated by either flg22 or SA. Interestingly, transient overexpression of GmMEKK1 in Nicotiana benthamiana also induced HR. Our results indicate that GmMEKK1 plays both positive and negative roles in immunity and appears to differentially activate downstream MPKs by promoting GmMPK6 activation but suppressing GmMPK3 activation in response to flg22. The involvement of GmMPK4 kinase activity in cell death and in flg22- or SA-triggered defense responses in soybean requires further investigation.

Retrospective Analysis of Intrathecal Drug Delivery: Outcomes, Efficacy, and Risk for Cancer-Related Pain at a High Volume Academic Medical Center

OBJECTIVES

Cancer pain is common and difficult to treat, as conservative medical management fails in approximately 20% of patients for reasons such as intolerable side-effects or failure to control pain. Intrathecal drug delivery systems (IDDS), while underutilized, can be effective tools to treat intractable cancer pain. This study aims to determine the degree of pain relief, efficacy, and safety of patients who underwent IDDS implantation at a multidisciplinary pain clinic.

MATERIALS AND METHODS

A retrospective review was conducted of patients with an intrathecal pain pump implanted for malignant pain. Charts were reviewed for demographics, cancer type, pain scores before and after implantation, and intrathecal drugs utilized. A Wilcoxon Signed-Rank test was conducted on the paired differences of pain scores before and after implant. A regression analysis was conducted using a linear model to assess effects of demographic variables on change in pain scores.

RESULTS

160 patients were included in analysis. The median pain score was 7.1 at time of implantation and 5.0 at one-month postimplantation. For patients with both baseline and one-month pain scores available, the median decrease in pain was 2.5 (p < 0.0001). Pain scores three-month postimplantation did not significantly differ from one-month postimplantation. Median longevity was 65 days. Five patients had pumps explanted due to infection with a median time to pump extraction of 28 days.

CONCLUSIONS

IDDS has the potential to improve cancer pain in a variety of patients and should be strongly considered as an option for those with cancer pain intractable to conservative medical management.

Reducing Radiation Exposure in Lumbar Transforaminal Epidural Steroid Injections with Pulsed Fluoroscopy: A Randomized, Doubleblind, Controlled Clinical Trial

Background: Fluoroscopy-guided lumbar transforaminal epidural steroid injections (L-TFESI) result in radiation exposure that carries risks to patients, physicians, and procedural staff. Objective: We aim to evaluate the feasibility of using pulsed fluoroscopy to safely reduce radiation exposure during L-TFESI. Study Design: This is a prospective, double-blind, randomized controlled trial. Setting: This study took place in a single-center, academic, outpatient interventional pain management clinic. Methods: Patients undergoing L-TFESI were randomly assigned to either continuous mode fluoroscopy (high-dose), pulsed fluoroscopy with 8 pulses per second (medium-dose), or pulsed fluoroscopy with one pulse per second (low-dose). Data on radiation doses and other clinical and demographic factors were also collected. Results: In total, 231 cases were analyzed in the high-dose group (n = 81), medium-dose group (n = 72), and low-dose group (n = 78). Mean radiation effective dose (µSv) was 121 in the highdose group, 57.9 in the medium-dose group, and 34.8 in the low-dose group (P < 0.001). The incidence of inadequate image quality in the pulsed groups was 6% (9/150). The body mass index (BMI, mean ± SD) was significantly higher in patients with inadequate image quality (37.3 ± 7.2) than with adequate quality (30.5 ± 7.2, P = 0.005). Limitations: Radiation doses were measured using the meter on C-arm fluoroscopes rather than by direct measurement. Conclusions: The use of pulsed fluoroscopy during L-TFESI resulted in radiation dose reduction of up to 72.1% without causing any significant adverse events. Pulsed fluoroscopy should be considered as an initial fluoroscopic setting for L-TFESI to reduce radiation exposure. Key words: Radiation, epidural, fluoroscopy, injection, exposure, pulse

Reducing Radiation Exposure in Lumbar Transforaminal Epidural Steroid Injections with Pulsed Fluoroscopy: A Randomized, Double-blind, Controlled Clinical Trial

BACKGROUND

Fluoroscopy-guided lumbar transforaminal epidural steroid injections (L-TFESI) result in radiation exposure that carries risks to patients, physicians, and procedural staff.

OBJECTIVE

We aim to evaluate the feasibility of using pulsed fluoroscopy to safely reduce radiation exposure during L-TFESI.

STUDY DESIGN

This is a prospective, double-blind, randomized controlled trial.

SETTING

This study took place in a single-center, academic, outpatient interventional pain management clinic.

METHODS

Patients undergoing L-TFESI were randomly assigned to either continuous mode fluoroscopy (high-dose), pulsed fluoroscopy with 8 pulses per second (medium-dose), or pulsed fluoroscopy with one pulse per second (low-dose). Data on radiation doses and other clinical and demographic factors were also collected.

RESULTS

In total, 231 cases were analyzed in the high-dose group (n = 81), medium-dose group (n = 72), and low-dose group (n = 78). Mean radiation effective dose (µSv) was 121 in the high-dose group, 57.9 in the medium-dose group, and 34.8 in the low-dose group (P < 0.001). The incidence of inadequate image quality in the pulsed groups was 6% (9/150). The body mass index (BMI, mean ± SD) was significantly higher in patients with inadequate image quality (37.3 ± 7.2) than with adequate quality (30.5 ± 7.2, P = 0.005).

LIMITATIONS

Radiation doses were measured using the meter on C-arm fluoroscopes rather than by direct measurement.

CONCLUSIONS

The use of pulsed fluoroscopy during L-TFESI resulted in radiation dose reduction of up to 72.1% without causing any significant adverse events. Pulsed fluoroscopy should be considered as an initial fluoroscopic setting for L-TFESI to reduce radiation exposure.

KEY WORDS

Radiation, epidural, fluoroscopy, injection, exposure, pulse.

Direct-acting antiviral treatment against hepatitis C virus infection in HIV-Infected patients - "En route for eradication"?

OBJECTIVES

Direct-Acting Antivirals (DAAs) opened a new era in HCV treatment. We report the impact of HCV treatment in French HIV-HCV coinfected patients.

METHODS

All HIV-HCV patients from the Dat'AIDS cohort followed between 2012 and 2015 were included. HCV status was defined yearly as naive, spontaneous cure, sustained virological response (SVR12), failure or reinfection.

RESULTS

Among 32,945 HIV-infected patients, 15.2% were positive for anti-HCV antibodies. From 2012 to 2015, HCV incidence rate increased from 0.35%PY to 0.69%PY in MSM, while median incidence was 0.08%PY in other patients. Median reinfection rate was 2.56%PY in MSM and 0.22%PY in other patients. HCV treatment initiation rate rose from 8.2% in 2012 to 29.6% (48.0% in pre-treated patients vs 22.6% in naïve patients). SVR12 rate increased from 68.7% to 95.2%. By the end of 2015, 62.7% of the patients were cured either spontaneously or following SVR.

CONCLUSIONS

HCV treatment dramatically increased in HIV-HCV patients in France from 2012 to 2015 resulting in HCV cure in nearly two-thirds of the patients in this cohort. Combined with a declining HCV prevalence, the prevalence of active HCV infection among HIV patients will drastically decrease in the forthcoming years.

A Small Cysteine-Rich Protein from the Asian Soybean Rust Fungus, Phakopsora pachyrhizi, Suppresses Plant Immunity

The Asian soybean rust fungus, Phakopsora pachyrhizi, is an obligate biotrophic pathogen causing severe soybean disease epidemics. Molecular mechanisms by which P. pachyrhizi and other rust fungi interact with their host plants are poorly understood. The genomes of all rust fungi encode many small, secreted cysteine-rich proteins (SSCRP). While these proteins are thought to function within the host, their roles are completely unknown. Here, we present the characterization of P. pachyrhizi effector candidate 23 (PpEC23), a SSCRP that we show to suppress plant immunity. Furthermore, we show that PpEC23 interacts with soybean transcription factor GmSPL12l and that soybean plants in which GmSPL12l is silenced have constitutively active immunity, thereby identifying GmSPL12l as a negative regulator of soybean defenses. Collectively, our data present evidence for a virulence function of a rust SSCRP and suggest that PpEC23 is able to suppress soybean immune responses and physically interact with soybean transcription factor GmSPL12l, a negative immune regulator.

Management of emerging multidrug-resistant tuberculosis in a low-prevalence setting

Multidrug-resistant (MDR) tuberculosis (TB) is an emerging concern in communities with a low TB prevalence and a high standard of public health. Twenty-three consecutive adult MDR TB patients who were treated at our institution between 2007 and 2013 were reviewed for demographic characteristics and anti-TB treatment management, which included surgical procedures and long-term patient follow-up. This report of our experience emphasizes the need for an individualized approach as MDR TB brings mycobacterial disease management to a higher level of expertise, and for a balance to be found between international current guidelines and patient-tailored treatment strategies.

Positive and negative roles for soybean MPK6 in regulating defense responses

It has been well established that MPK6 is a positive regulator of defense responses in model plants such as Arabidopsis and tobacco. However, the functional importance of soybean MPK6 in disease resistance has not been investigated. Here, we showed that silencing of GmMPK6 in soybean using virus-induced gene silencing mediated by Bean pod mottle virus (BPMV) caused stunted growth and spontaneous cell death on the leaves, a typical phenotype of activated defense responses. Consistent with this phenotype, expression of pathogenesis-related (PR) genes and the conjugated form of salicylic acid were significantly increased in GmMPK6-silenced plants. As expected, GmMPK6-silenced plants were more resistant to downy mildew and Soybean mosaic virus compared with vector control plants, indicating a negative role of GmMPK6 in disease resistance. Interestingly, overexpression of GmMPK6, either transiently in Nicotiana benthamiana or stably in Arabidopsis, resulted in hypersensitive response (HR)-like cell death. The HR-like cell death was accompanied by increased PR gene expression, suggesting that GmMPK6, like its counterpart in other plant species, also plays a positive role in cell death induction and defense response. Using bimolecular fluorescence complementation analysis, we determined that GmMKK4 might function upstream of GmMPK6 and GmMKK4 could interact with GmMPK6 independent of its phosphorylation status. Taken together, our results indicate that GmMPK6 functions as both repressor and activator in defense responses of soybean.

Epidemiology and clinical significance of non-tuberculous mycobacteria isolated from pulmonary specimens

SETTING

A tertiary university medical centre in northern Israel.

OBJECTIVE

To evaluate the clinical significance of non-tuberculous mycobacteria (NTM) isolated from pulmonary specimens.

DESIGN

Clinical and microbiological data were collected from patient files. Cases were classified as definite, probable and possible NTM.

RESULTS

Between 2004 and 2010, 215 cases with respiratory isolates of NTM were identified. Mycobacterium xenopi was the most common species (n = 84, 39.1%), followed by M. simiae (n = 52, 24.2%). A total of 170 (79.1%) cases were classified as possible and 24 (11.2%) as probable NTM. Only 21 (9.8%) cases were considered definite NTM, the majority of which were M. kansasii and M. avium complex.

CONCLUSIONS

M. xenopi and M. simiae are the most prevalent species of NTM isolated from respiratory samples in northern Israel. However, most of these isolates represent colonisation. Of the relatively small number of clinically significant isolates, M. kansasii and M. avium complex were the most common.

Soybean homologs of MPK4 negatively regulate defense responses and positively regulate growth and development

Mitogen-activated protein kinase (MAPK) cascades play important roles in disease resistance in model plant species such as Arabidopsis (Arabidopsis thaliana) and tobacco (Nicotiana tabacum). However, the importance of MAPK signaling pathways in the disease resistance of crops is still largely uninvestigated. To better understand the role of MAPK signaling pathways in disease resistance in soybean (Glycine max), 13, nine, and 10 genes encoding distinct MAPKs, MAPKKs, and MAPKKKs, respectively, were silenced using virus-induced gene silencing mediated by Bean pod mottle virus. Among the plants silenced for various MAPKs, MAPKKs, and MAPKKKs, those in which GmMAPK4 homologs (GmMPK4s) were silenced displayed strong phenotypes including stunted stature and spontaneous cell death on the leaves and stems, the characteristic hallmarks of activated defense responses. Microarray analysis showed that genes involved in defense responses, such as those in salicylic acid (SA) signaling pathways, were significantly up-regulated in GmMPK4-silenced plants, whereas genes involved in growth and development, such as those in auxin signaling pathways and in cell cycle and proliferation, were significantly down-regulated. As expected, SA and hydrogen peroxide accumulation was significantly increased in GmMPK4-silenced plants. Accordingly, GmMPK4-silenced plants were more resistant to downy mildew and Soybean mosaic virus compared with vector control plants. Using bimolecular fluorescence complementation analysis and in vitro kinase assays, we determined that GmMKK1 and GmMKK2 might function upstream of GmMPK4. Taken together, our results indicate that GmMPK4s negatively regulate SA accumulation and defense response but positively regulate plant growth and development, and their functions are conserved across plant species.

Biphasic gene expression changes elicited by Phakopsora pachyrhizi in soybean correlate with fungal penetration and haustoria formation

Inoculation of soybean (Glycine max) plants with Phakopsora pachyrhizi, the causal organism of Asian soybean rust, elicits a biphasic response characterized by a burst of differential gene expression in the first 12 h. A quiescent period occurs from 24 to 48 h after inoculation, in which P. pachyrhizi continues to develop but does not elicit strong host responses, followed by a second phase of intense gene expression. To correlate soybean responses with P. pachyrhizi growth and development, we inoculated the soybean cultivar Ankur (accession PI462312), which carries the Rpp3 resistance gene, with avirulent and virulent isolates of P. pachyrhizi. The avirulent isolate Hawaii 94-1 elicits hypersensitive cell death that limits fungal growth on Ankur and results in an incompatible response, while the virulent isolate Taiwan 80-2 grows extensively, sporulates profusely, and produces a compatible reaction. Inoculated leaves were collected over a 288-h time course for microarray analysis of soybean gene expression and microscopic analysis of P. pachyrhizi growth and development. The first burst in gene expression correlated with appressorium formation and penetration of epidermal cells, while the second burst of gene expression changes followed the onset of haustoria formation in both compatible and incompatible interactions. The proliferation of haustoria coincided with the inhibition of P. pachyrhizi growth in the incompatible interaction or the beginning of accelerated growth in the compatible interaction. The temporal relationships between P. pachyrhizi growth and host responses provide an important context in which to view interacting gene networks that mediate the outcomes of their interactions.

Safety analysis of radioimmunotherapy (RIT) in patients with relapsed or refractory low grade, follicular or transformed non-Hodgkin's lymphoma and mantle cell lymphoma based on age at time of therapy

e19529

Background: Radioimmunotherapy is a therapeutic option for relapsed or refractory indolent, follicular and transformed non Hodgkin's lymphoma and mantle cell lymphoma. Although prolongued myelotoxicity has been described with use of iodine I 131 tositumomab (TOSI) and yttrium 90 ibritumomab tiuxetan (IBRI), analysis of toxicity according to patients’ age at therapy still lacks. Methods: Utilizing the Rush University Medical Center database 61 subjects who received RIT between November/2003 and June/2008, either with TOSI or IBRI were divided in 2 groups according to age at time of therapy. Group 1 included patients between 33 and 60 (51.8±6.5) years of age (N=29) and group 2 included patients 61 years old or older (70.1±7.8) (N=32). Parameters compared between groups were: Time to nadir of lowest absolute neutrophil count (ANC), time to recovery ANC above 1000/mcL, time to nadir of lowest hemoglobin levels, time to recovery to hemoglobin levels above 8g/dL, time to lowest platelet count and time to recovery to platelet count above 100,000/mcL. Incidence o myelodysplastic syndrome (MDS) was also compared between groups. Groups characteristics such as sex, type of RIT, presence of disease in bone marrow, FLIPI/IPI and use of G-CSF were noted. Results: There was no significant statistical difference between groups in time (number of days) to achieve nadir of ANC (group 1 85.3±208; group 2 50.3±19.9), nadir of hemoglobin levels (group 1 106±60.6; group 2 84±57.0) and time to nadir of platelet level (group 1 53.5±70.7; group 2 41.8±9.6). There was no statistical significant difference between groups in duration of cytopenias, except for time for platelet recovery which was significant longer in group 2 using the Pearson Correlation analysis. (p=0.008). (Days for platelets recovery to levels above 100,000/mcL group 1 29.4±27.7; group 2 108.8 ±207.3). One patient in group 1 and three patients on group 2 were diagnosed with MDS but were also treated with different chemotherapy regimens. Conclusions: RIT should be considered a safe therapeutic modality in patients with refractory or relapsed indolent, follicular, NHL, transformed and Mantle Cell lymphoma regardless of age.

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