Vλ-light chain genes reconstitute immune responses to defined carbohydrate antigens or haptens by utilizing different VH genes

The contribution of the λ-light chain to the development of peripheral B cell repertoire and generation of specific antibodies to haptens and polysaccharide antigens was studied in genetically manipulated kappa-deficient and λ₂-transgenic mice. The results clearly demonstrate a non-stoichiometric V_H gene family expression in the absence of k-light chain and suggest a non-stochastic pairing between V_H and V_λ genes, expressed in the peripheral B cell repertoire. A shift in V_H gene utilization in the case of Vl_λ⁺ antibodies was evident in response to β2–6 fructosan and TNP hapten. These observations demonstrate the availability of compensatory mechanisms in the absence of V_K genes and are consistent with the hypothesis that V_H gene family expression is controlled by genetic factors from inside the V_H locus. Furthermore, genetic factors from outside the V_H locus, namely restricted available light chain diversity, may lead to a shift in V_H gene utilization in the peripheral B cell repertoire.     

Treating obesity in patients with cardiovascular disease: the pharmacotherapeutic options

Introduction: Obesity is a growing health problem that has numerous comorbidities, including cardiovascular disease (CVD). The multi-disciplinary treatment of obesity now includes the use of pharmacotherapy. When treating patients with obesity and CVD, certain medications may be more appropriate than others.

Areas covered: Herein, the authors review the most commonly used FDA approved medications for the treatment of obesity, describing their mechanism of action, and the efficacy and safety of the medications as seen in recent studies, particularly in patients with CVD.

Expert opinion: In the population of patients with obesity and CVD, the medications orlistat, lorcaserin and liraglutide are considered the most appropriate options for their treatment, in terms of safety. Sympathomimetic medications, such as phentermine, should be avoided in this group. The recent CAMELLIA-TIMI 61 trial supports the safety of lorcaserin in patients with CVD. Until there are more studies, it is reasonable to extrapolate the findings of the LEADER trial, which found improved CV outcomes in subjects with type 2 diabetes taking liraglutide, to the population of nondiabetic patients being treated for obesity. Further cardiovascular outcomes trials (CVOT) are needed to assess the safety of other pharmacotherapeutic options for weight loss.     

Biodistribution and targeting potential assessment of mucoadhesive chitosan nanoparticles designed for ulcerative colitis via scintigraphy

In the present investigation we have prepared and characterized curcumin (CN)-containing chitosan nanoparticles (CS-NPs) coated with Eudragit FS 30D for colon-specific drug delivery for treatment of ulcerative colitis. Methods: CS-NPs were prepared by ionic gelation using tripolyphosphate. To specify pH sensitive delivery, CS–CN-NPs were coated with Eudragit FS 30D by using a solvent evaporation method. Different process parameters were evaluated, and the optimized formulation was characterized by particle size, size distribution, zeta potential and encapsulation efficiency before lyophilization. The lyophilized product was further subjected to Fourier-transform infrared spectroscopy, and particle morphology and in vitro drug release in different media were studied. Results: the kinetics of in vitro drug release from the CS–CN-NPs revealed sustained release behaviour of the developed carriers. In vivo biodistribution study by gamma-scintigraphy showed good accumulation of the developed nanocarriers in the colonic region. Conclusion: sustained and pH stimulated delivery of CN to the colon was successfully attained via coating of CS-NPs with Eudragit FS 30D to circumvent poor absorption and availability of CN.

In the present investigation we have prepared and characterized curcumin (CN)-containing chitosan nanoparticles (CS-NPs) coated with Eudragit FS 30D for colon-specific drug delivery for treatment of ulcerative colitis.     

Alveolar soft part sarcoma of the retroperitoneum: A case report

Alveolar soft part sarcoma is a rare soft tissue tumor with uncertain histogenesis. It is a slow growing tumor with a high rate of metastasis. The tumor is not easily identified as clinical symptoms are not pronounced. The retroperitoneum is a rare location of tumor, with a few cases published in literature. Surgical excision is the mainstay of treatment. Here we describe a rare case of a large retroperitoneal Alveolar soft part sarcoma in a young female with radiological and histopathological findings.     

Pharmacokinetics of anthocyanins and ellagic acid in healthy volunteers fed freeze-dried black raspberries daily for 7 days

Eleven subjects completed a clinical trial to determine the safety/tolerability of freeze-dried black raspberries (BRB) and to measure, in plasma and urine, specific anthocyanins-cyanidin-3-glucoside, cyanidin-3-sambubioside, cyanidin-3-rutinoside, and cyanidin-3-xylosylrutinoside, as well as ellagic acid. Subjects were fed 45 g of freeze-dried BRB daily for 7 days. Blood samples were collected predose on days 1 and 7 and at 10 time points postdose. Urine was collected for 12 hours predose on days 1 and 7 and at three 4-hour intervals postdose. Maximum concentrations of anthocyanins and ellagic acid in plasma occurred at 1 to 2 hours, and maximum quantities in urine appeared from 0 to 4 hours. Overall, less than 1% of these compounds were absorbed and excreted in urine. None of the pharmacokinetic parameters changed significantly between days 1 and 7. In conclusion, 45 g of freeze-dried BRB daily are well tolerated and result in quantifiable anthocyanins and ellagic acid in plasma and urine.     

Biomarkers of cardiac injury: an update

Conventional and promising new markers of myocardial injury have become an important diagnostic tool and their prognostic significance is also recognized. In addition, they help identify patients who will derive the most benefit from therapeutic interventions. The literature was searched from the websites of the National Library of Medicine (http://www.ncbi.nlm.nih.gov/) and PubMed Central, the U.S. National Library of Medicine's digital archive of life sciences journal literature (http://www.pubmedcentral.nih.gov/). The data were accessed from books and journals that published relevant articles in this field. The diagnosis of acute myocardial infarction (AMI) has traditionally relied on the combination of chest pain, ECG features, and elevation in serum markers. However, chest symptoms are frequently atypical or absent and ECG changes may be nonspecific or absent. Hence, the diagnosis of acute coronary syndromes has become increasingly dependent on serum markers of cardiac injury. Among them, creatine kinase (CK) is an effective and widely used test, with the recent CKMB assay offering greater specificity and sensitivity. Cardiac troponins facilitate early and rapid diagnosis, enable effective risk stratification in patients with AMI (with or without traditional criteria for MI), and identify those who will benefit from aggressive medical or surgical intervention. Recent data suggest the potential of myoglobin and CKMB isoforms as sensitive markers in the early hours after symptom onset. Cardiac-specific troponins help in rapid diagnosis, prognostication, and treatment of AMI. Troponins also facilitate early detection of recent infarction owing to their prolonged diagnostic window and also aid in the detection of "microinfarction.' CKMB is used to detect reinfarction or infarct extension, if levels rise again after declining. Finally, novel biochemical markers are receiving attention in ongoing trials. They may prove to be more effective in diagnosis and prognosis than their existing counterparts.     

Silibinin causes cell cycle arrest and apoptosis in human bladder transitional cell carcinoma cells by regulating CDKI-CDK-cyclin cascade, and caspase 3 and PARP cleavages

Bladder cancer is the fourth and eighth most common cancer in men and women in the USA, respectively. Flavonoid phytochemicals are being studied for both prevention and therapy of various human malignancies including bladder cancer. One such naturally occurring flavonoid is silibinin isolated from milk thistle. Here, we assessed the effect of silibinin on human bladder transitional cell carcinoma (TCC) cell growth, cell cycle modulation and apoptosis induction, and associated molecular alterations, employing two different cell lines representing high-grade invasive tumor (TCC-SUP) and high-grade TCC (T-24) human bladder cancer. Silibinin treatment of these cells resulted in a significant dose- and time-dependent growth inhibition together with a G(1) arrest only at lower doses in TCC-SUP cells but at both lower and higher doses in T-24 cells; higher silibinin dose showed a G(2)/M arrest in TCC-SUP cells. In other studies, silibinin treatment strongly induced the expression of Cip1/p21 and Kip1/p27, but resulted in a decrease in cyclin-dependent kinases (CDKs) and cyclins involved in G(1) progression. Silibinin treatment also showed an increased interaction between cyclin-dependent kinase inhibitors (CDKIs)-CDKs and a decreased CDK kinase activity. Further, the G(2)/M arrest by silibinin in TCC-SUP cells was associated with a decrease in pCdc25c (Ser216), Cdc25c, pCdc2 (Tyr15), Cdc2 and cyclin B1 protein levels. In additional studies, silibinin showed a dose- and a time-dependent apoptotic death only in TCC-SUP cells that was associated with cleaved forms of caspase 3 and poly(ADP-ribose) polymerase. Together, these results suggest that silibinin modulates CDKI-CDK-cyclin cascade and activates caspase 3 causing growth inhibition and apoptotic death of human TCC cells, providing a strong rationale for future studies evaluating preventive and/or intervention strategies for silibinin in bladder cancer pre-clinical models.     

Grape seed extract inhibits EGF-induced and constitutively active mitogenic signaling but activates JNK in human prostate carcinoma DU145 cells: possible role in antiproliferation and apoptosis

A loss of functional androgen receptor and an enhanced expression of growth factor receptors and associated ligands are causal genetic events in prostate cancer (PCA) progression. These genetic alterations lead to an epigenetic mechanism where a feedback autocrine loop between membrane receptor and ligand (e.g. EGFR-TGFalpha) results in a constitutive activation of MAPK-Elk1-AP1-mediated mitogenic signaling in human PCA at an advanced and androgen-independent stage. We rationalized that inhibiting these epigenetic events could be useful in controlling advanced PCA growth. Recently, we found that grape seed extract (GSE), a dietary supplement rich in flavonoid procyanidins, inhibits advanced and androgen-independent human PCA DU145 cell growth in culture and nude mice. Here, we performed detailed mechanistic studies to define the effect of GSE on EGFR-Shc-MAPK-Elk1-AP1-mediated mitogenic signaling in DU145 cells. Pretreatment of serum-starved cells with GSE resulted in 70% to almost complete inhibition of EGF-induced EGFR activation and 50% to complete inhibition of Shc activation, which corroborated with a comparable decrease in EGF-induced Shc binding to EGFR. Conversely, EGF-induced ERK1/2 phosphorylation was inhibited only by lower doses of GSE; in fact, higher doses showed an increase. Additional studies showed that GSE alone causes a dose- and time-dependent increase in ERK1/2 phosphorylation in starved DU145 cells that is inhibited by an MEK1 inhibitor PD98059. Independent of this increase in ERK1/2 phosphorylation, GSE showed a strong inhibition of ERK1/2 kinase activity to Elk1 in both cellular and cell-free systems. GSE treatment of cells also inhibited both EGF-induced and constitutively active Elk1 phosphorylation and AP1 activation. GSE treatment also showed DNA synthesis inhibition in starved and EGF-stimulated cells as well as loss of cell viability and apoptotic death that was further increased by adding MEK1 inhibitor. Since GSE strongly induced apoptosis independent of its affect on an increase in phospho-ERK1/2, we hypothesized that apoptotic effect of GSE could be by other mechanism(s) including its effect on stress-associated MAPK, the JNK. Indeed, GSE-treated cells showed a strong and sustained increase in phospho-JNK1/JNK2 levels, JNK activity and phospho-cJun levels. An inhibition of GSE-induced JNK activation by a novel JNK inhibitor SP600125 resulted in a significant reversal of GSE-induced apoptotic death suggesting the involvement of JNK activation by GSE in its apoptosis response. Together, these results suggest that anticancer effects of GSE in PCA be mediated via impairment of EGFR-ERK1/2-Elk1-AP1-mediated mitogenic signaling and activation of JNK causing growth inhibition and apoptosis, respectively.