C-C chemokine receptor regulates the antibody response to DNP-KLH (P6351)

Functional loss of C-C chemokine receptor 7 (CCR7) and its ligands, CCL19 and CCL21, has been linked to development of autoimmune diseases. Therefore, we hypothesized that CCR7 antagonists could be used to promote an immune response that could be measured by tittering antibodies produced in animals injected with test antigens. To test this hypothesis we injected C57BL/6 mice on day 0 and boosted on day 20 with dinitrophenol (DNP)-Keyhole Limpet Hemocyanin (KLH) with a CCL19 antagonist, 8-83, or with the agonist solvent as a control. Similar to the CCR7-/- mouse, which has significantly elevated levels of IgG1, IgG2a, IgG2b and IgG3 by day 30, the animals treated with 8-83 generated significantly higher levels of IgG1 and IgG2a, than animals injected with the DNP-KLH/solvent alone. Previous studies by our laboratory have shown that CCL19 signals through ERK5. To determine if loss of signaling through ERK induced a similar increase in the levels of IgGs, we injected ERK5flox/flox control mice or ERK5flox/floxLck-Cre mice with DNP-KLH. Similar to animals treated with 8-83, the ERK5flox/flox Lck-Cre mice produced significantly higher levels of IgG1, IgG2a and IgG3 than control mice. From these results we conclude that CCR7/CCL19 signals through ERK5 to control the levels of antibodies made. Recent studies demonstrating a role for CCR7 in controlling the localization of regulatory T cells may provide insight into immune cells that are regulate observed increase in antibody titers.

Abstract 3734: Cancer stem cells: novel chemopreventive targets for pancreatic cancer

Pancreatic cancer is the fourth leading cause of mortality in the United States and no significant treatment is currently available. Although an increasing number of therapeutic options exist for patients with advanced disease, their efficacy is time limited and non-curative. Presently approximately close to 60% of cancer patients in the United States are believed to utilize therapies derived from plants, herbs, flowers, or nutrients either exclusively or concurrently with traditional chemotherapy or radiation therapy.

Recent evidence suggests the existence of a small population of tumorigenic stem cells responsible for tumor initiation, metastasis and resistance to chemotherapy and radiation. Identification of the regulatory mechanisms and signaling pathways involved in cancer stem cells (CSCs) will help in designing novel agents to target this refractory cell population in pancreatic cancers.

We are currently investigating the mechanisms by which purified crocetinic acid, a carotenoid molecule isolated from saffron, inhibits growth of pancreatic cancer in vitro and in vivo models. Our studies demonstrate that the compound had significant cytotoxicity against pancreatic cancer cells in both a dose- and time-dependent manner. Pancreatic CSCs can be allowed to divide and grow in ultra-low binding tissue culture dishes to form multicellular spheroids called pancospheres. Treatment with purified crocetinic acid decreased the number and size of the primary and secondary pancospheres in a dose dependent manner, suggesting that crocetinic acid targets CSCs. To understand the mechanism of inhibition of pancospheres, the signaling pathways affected by crocetinic acid were dissected. Aberrant activation of Sonic Hedgehog signaling pathway has been associated with renewal of cancer stem cells, and in the development of several solid cancers. Sonic hedgehog (Shh) upon binding to its cognate receptor patched, allows smoothened to accumulate and activate Gli transcription factor. Treatment with crocetinic acid inhibited the expression of both Shh and smoothened in the pancreatic CSCs with concomitant reduction of the expression of a novel pancreatic CSC marker, DCLK-1 (Doublecortin Calcium/Calmodulin-Dependent Kinase-1). Furthermore, it inhibited the expression of patched-1 and Gli-1, downstream targets of the hedgehog signaling pathway. Crocetinic acid also inhibited tumor formation in pancreatic cancer in vivo xenograft models.

Taken together, these data suggest that crocetinic acid effectively inhibits pancreatic CSCs by down regulating the sonic hedgehog pathway, thereby inhibiting tumorigenesis.

Citation Format: Parthasarathy Rangarajan, Dharmalingam Subramaniam, Deep Kwatra, Shamima Islam, Kanagaraj Palaniyandi, Shrikant Anant, Animesh Dhar. Cancer stem cells: novel chemopreventive targets for pancreatic cancer. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 3734. doi:10.1158/1538-7445.AM2013-3734

Ultrasound evaluation of traumatic patient in a tertiary level hospital

This study was designed to assess the use of ultrasonography in evaluation of trauma patients to see any intraperitoneal collection, collection in pleural cavity, any vital organ injury or any localized collection in blunt trauma to abdomen. This cross sectional study was performed in patient having history of trauma who attended the Centre for Nuclear Medicine & Ultrasound (CNM&U), Mymensingh for ultrasonic evaluation. Ultrasonography scanning was done to see any intraperitoneal collection, pleural collection or vital organ injury. Vulnerable age, causes of trauma, types of organ injury and relation between ages & types of organ involved were also evaluated. Fifty patients were evaluated among those 44(88%) were male & 6(12%) were female. Ultrasonographic examination detected 26(52%) patients with intraperitoneal collection, 13(26%) patients with intraabdominal organ injury, 5(10%) patients with pleural collection. Liver (30%) is the mostly affected organ. It was also found that the most vulnerable age having trauma to abdomen was 11 to 30 (54%) years. The most common cause of trauma was road traffic accident (46%). Younger people were more vulnerable to liver and pancreatic injury, older people to splenic injury and middle aged to renal injury. Ultrasonography is a useful primary tool for evaluating traumatic patient specially to detect intraperitoneal collection and organ injury in country like Bangladesh where accidental injury is very common.

Identification of potential targets in Staphylococcus aureus N315 using computer aided protein data analysis

Staphylococcus aureus is a gram positive bacterium, responsible for both community-acquired and hospital-acquired infection, resulting in a mortality rate of 39%. 43.2% resistance to methicilin and emerging resistance to Fluroquinolone and Oxazolidinone, have evoked the necessity of the establishment of alternative and effective therapeutic approach to treat this bacteria. In this computational study, various database and online software are used to determine some specific targets of Staphylococcus aureus N315 other than those used by Penicillin, Quinolone and Oxazolidinone. For this purpose, among 302 essential proteins, 101 nonhomologous proteins were accrued and 64 proteins which are unique in several metabolic pathways of S. aureus were isolated by using metabolic pathway analysis tools. Furthermore, 7 essentially unique enzymes involved in exclusive metabolic pathways were revealed by this research, which can be potential drug target. Along with these important enzymes, 15 non-homologous proteins located on membrane were identified, which can play a vital role as potential therapeutic targets for the future researchers.

Increased cardiovascular risk after pre-eclampsia in women with dysglycaemia

AIMS

Compared with women with uncomplicated pregnancies, women with a history of pre-eclampsia have two to five times the risk of cardiovascular disease. It is not known whether this risk is related to albuminuria, a known cardiovascular risk factor that is part of the definition of pre-eclampsia and that often persists after delivery. Our objective was to determine if the high risk of cardiovascular disease in women with pre-eclampsia is accounted for by known cardiovascular risk factors including albuminuria.

METHODS

We performed a cross-sectional analysis of 4080 dysglycaemic women enrolled in a large randomized controlled trial who provided an obstetric history and had at least one delivery. Blood pressure, height, weight, waist circumference and hip circumference were measured. An oral glucose tolerance test, lipids, an electrocardiogram and an albumin/creatinine ratio from a first morning urine sample were obtained.

RESULTS

There were 3613 women with no history of pre-eclampsia during their pregnancies, 108 with severe pre-eclampsia and 359 with non-severe pre-eclampsia. Women with a history of severe pre-eclampsia had higher rates of previous cardiovascular disease than women with non-severe pre-eclampsia or women without pre-eclampsia (87, 72 and 72%, P = 0.0019). The high risk of previous cardiovascular disease in women with a history of severe pre-eclampsia (odds ratio 2.67, 95% CI 1.52-4.70) persisted after adjustment for albuminuria (odds ratio 2.74, 95% CI 1.55-4.83) and also after adjusting for other covariates including albuminuria (odds ratio 3.03, 95% CI 1.69-5.44).

CONCLUSION

Even after accounting for cardiovascular risk factors including albuminuria, a history of severe pre-eclampsia is independently associated with a threefold higher risk of cardiovascular disease.

Use of fluorescein diacetate (FDA) staining to detect viable Mycobacterium tuberculosis

Objective: Drug resistant tuberculosis has long been a common problem prevailing in developing countries including Bangladesh. Present study focused on the rapid identification of live Mycobacterium tuberculosis among treatment failure cases.Materials and Methods: Sputum samples from a total of 100 category-I and category-II treatment failure cases, assumed as multidrug resistant tuberculosis, were studied through fluorescein diacetate (FDA) staining under light emitting diode (LED) fluorescence microscope. Considering culture method as gold standard, we also compared the results of FDA staining with that of auramine O staining.Results: A total of 85% acid-fast bacilli were detected by FDA staining, 82% by auramine O staining and a total of 85% isolates were detected in Lowenstein-Jensen (LJ) culture. The sensitivity of FDA staining (96.47%) was estimated to be slightly higher than that of auramine O staining (91.76%). Moreover,76.47% cases were detected as multidrug resistant tuberculosis (MDR-TB). Conclusion: Taken together, FDA staining method has been proposed to be appropriate for the rapid diagnosis of drug resistant tuberculosis. DOI: http://dx.doi.org/10.3329/bjms.v11i4.12605 Bangladesh Journal of Medical Science Vol. 11 No. 04 Oct’12

Temperature stability of ultra-thin mixed BaSr-oxide layers and their transformation

In the context of investigations of physical, chemical and electrical properties of ultra-thin layers of epitaxial and monocrystalline Sr(0.3)Ba(0.7)O on Si(100), we also investigated their thermal stability with x-ray photoelectron spectroscopy (XPS), electron energy loss spectroscopy (EELS), and low energy electron diffraction (LEED). At temperatures above 400 °C, transformation into silicate layers sets in. The stoichiometry after complete transformation was determined to be close to (Ba(0.8)Sr(0.2))(2)SiO(4) except for layers of only a few monolayers, where the silicate is not stoichiometric. There are strong indications that this silicate is stable until it desorbs at temperatures above 750 °C. Crystallinity, as seen with LEED, is lost during this transformation. Although transformation into silicate is coupled with metal desorption and compactification of the layers, they seem to remain closed. In addition, traces of Ba silicide at the Si interface were detected after layer desorption. This silicide cannot be desorbed thermally. The silicate layer has a bandgap of 5.9 ± 0.2 eV already for 3 ML thickness. Upon exposure to air, carbon and oxygen containing species, but no hydroxide, are formed irreversibly.

Microvascular reconstruction of the mouth, face and jaws. Oromandibular reconstruction - free fibula flap

Dental surgeons may encounter in their clinical practice patients who present with aggressive pathologies that require early diagnosis and prompt treatment. This action may limit the extent of tissue damage and, where relevant, improve survival outcome. Clinicians should therefore be aware of the range of resective, reconstructive and rehabilitative options that are available in the management of these patients. We present our experience with the free fibula flap used for oromandibular reconstruction; this was undertaken in 21 patients following resective surgery for malignant pathology, cytologically benign but biologically aggressive odontogenic pathology and radiation induced osteonecrosis. We also review the history, surgical anatomy, surgical assessment and potential complications that are relevant to the free fibula flap.

A longitudinal study of resolution of allergy to well-cooked and uncooked egg

BACKGROUND

Egg allergy is common and although resolution to uncooked egg has been demonstrated, there is lack of evidence to guide reintroduction of well-cooked egg.

OBJECTIVES

To examine the rate of resolution to well-cooked, compared with uncooked egg in children, and safety of egg challenges.

METHOD

A longitudinal study of egg-allergic children from 2004 to 2010, who underwent challenge with well-cooked and if negative, uncooked egg. Participants underwent repeat annual challenges and egg-specific IgE measurement.

RESULTS

One hundred and eighty-one open egg challenges were performed in 95 children whose median age of allergy onset was 12 months. Fifty-three of 95 (56%) had at least one annual repeat challenge. Pre-study historical reactions occurred to baked egg in five (5%), lightly cooked in 58 (61%) and uncooked in nine (9%); respiratory reactions occurred in 11 (12%) and seven (7%) had anaphylaxis; adrenaline was used during five reactions. There were 77 well-cooked and 104 uncooked egg challenges. Tolerance was gained twice as rapidly to well-cooked than uncooked egg (median 5.6 vs. 10.3 years; P<0.0001) and continued to 13 years; hazard ratio 2.23 (95% confidence interval 1.6-3.9). Nearly 1/3 had resolved allergy to well-cooked egg at 3 years and 2/3 at 6 years. Of 28/77 (37%) positive well-cooked egg challenges, 65% had cutaneous symptoms, 68% gastrointestinal and 39% rhinitis, with no other respiratory reactions. Adrenaline was not required. CONCLUSIONS AND CLINICAL RELEVANCE RESOLUTION: of egg allergy takes place over many years, with children outgrowing allergy to well-cooked egg approximately twice as quickly as they outgrow allergy to uncooked egg. There were no severe reactions to well-cooked egg challenge, and adrenaline was not required. Our data support initiation of home reintroduction of well-cooked egg from 2 to 3 years of age in children with previous mild reactions and no asthma. Resolution continues to occur in older children, so that despite an earlier positive challenge, attempts at reintroduction should be continued.

BRCA1 protein levels and PIK3CA mutations as predictive biomarkers for response to neoadjuvant chemotherapy in locally advanced breast cancer: An exploratory analysis

BRCA1 overexpression and phosphoinositide 3-kinase (PIK3CA) pathway activation are involved in the resistance to DNA damaging agents. Thus, we hypothesized that BRCA1 protein expression and activating PIK3CA mutations are potential tumor biomarkers for the chemotherapeutic response to doxorubicin/cyclophosphamide plus docetaxel in locally advanced breast cancer. Informed consent was obtained and clinical, pathological and response data were collected. BRCA1 protein expression levels were assessed by immunohistochemistry of the archived tissue by two independent pathologists. The PIK3CA mutation status was assessed by nested PCR amplification and DNA sequencing. BRCA1 protein levels and the PIK3CA mutation status were correlated with pathological complete response and a partial response or better using the Chi-square test, Fisher's exact test and logistic regression. Of the 136 eligible participants, 59 samples could be analyzed. There was a trend of relatively low levels of BRCA1 protein achieving a pathological complete response (pCR), although this was not statistically significant [odds ratio (OR)=1.74; p=0.437]. Twenty-eight percent of patients had PIK3CA mutations, but no statistically significant association with pCR (OR=0.977; p=0.971) was noted. Neither BRCA1 protein levels (OR=1.18; p=0.818) nor PIK3CA mutations (OR=1.03; p=0.971) appeared to be associated with the likelihood of achieving a partial response or better from neoadjuvant chemotherapy. PIK3CA wild-type mutation status showed a trend towards an increased likelihood of not presenting with inflammatory disease (OR=5.34; p=0.101). In this exploratory study, neither BRCA1 protein expression levels nor the presence of PIK3CA mutations were significantly associated with chemotherapy response in locally advanced breast cancer. However, the relatively small sample size limits the overall interpretation.

Thermographic imaging during nasal peanut challenge may be useful in the diagnosis of peanut allergy

BACKGROUND

Double-blinded challenges are widely used for diagnosing food allergy but are time-consuming and cause severe reactions. Outcome relies on subjective interpretation of symptoms, which leads to variations in outcome between observers. Facial thermography combined with nasal peanut challenge was evaluated as a novel objective indicator of clinical allergy.

METHODS

Sixteen children with positive blinded peanut challenge underwent nasal challenge with 10 μg peanut protein or placebo. Mean skin temperatures were recorded from the mouth and nose using infrared thermography over 18 min.

RESULTS

The area under curve of nasal skin temperature was significantly elevated after peanut vs placebo (18.2 vs 4.8°Cmin). The maximum increase in temperature was also significantly greater after peanut: mean difference +0.9°C.

CONCLUSION

This feasibility study shows thermography can detect inflammation caused by nasal challenges whilst employing one thousand-fold less peanut than an oral challenge. This novel technique could be developed to provide a rapid, safe and objective clinical allergy test.

Devoid of dentistry

Dental curricula in UK dental schools are seemingly excising ever more skills as each generation of students is trained. This has implications for the quality of education held by the latest dental graduates, and furthermore potentially for the standard of care that their patients may receive. This leaves us today somewhat nostalgic for a bygone era when dental undergraduate education was replete with a fuller repertoire.

CCR7/CCL19 controls expression of EDG-1 in T cells

T lymphocytes circulate between the blood, tissues, and lymph. These T cells carry out immune functions, using the C-C chemokine receptor 7 (CCR7) and its cognate ligands, CCL19 and CCL21, to enter and travel through the lymph nodes. Distinct roles for each ligand in regulating T lymphocyte trafficking have remained elusive. We report that in the human T cell line HuT78 and in primary murine T lymphocytes, signaling from CCR7/CCL19 leads to increased expression and phosphorylation of extracellular signal-regulated kinase 5 (ERK5) within eight hours of stimulation. Within 48-72 h we observed peak levels of endothelial differentiation gene 1 (EDG-1), which mediates the egress of T lymphocytes from lymph nodes. The increased expression of EDG-1 was preceded by up-regulation of its transcription factor, Krüppel-like factor 2 (KLF-2). To determine the cellular effect of disrupting ERK5 signaling from CCR7, we examined the migration of ERK5(flox/flox)/Lck-Cre murine T cells to EDG-1 ligands. While CCL19-stimulated ERK5(flox/flox) naïve T cells showed increased migration to EDG-1 ligands at 48 h, the migration of ERK5(flox/flox)/Lck-Cre T cells remained at a basal level. Accordingly, we define a novel signaling pathway that controls EDG-1 up-regulation following stimulation of T cells by CCR7/CCL19. This is the first report to link the two signaling events that control migration through the lymph nodes: CCR7 mediates entry into the lymph nodes and EDG-1 signaling controls their subsequent exit.