Anaplasma phagocytophilum induces Ixodes scapularis ticks to express an antifreeze glycoprotein gene that enhances their survival in the cold

In the United States, Ixodes scapularis ticks overwinter in the Northeast and Upper Midwest and transmit the agent of human granulocytic anaplasmosis, Anaplasma phagocytophilum, among other pathogens. We now show that the presence of A. phagocytophilum in I. scapularis ticks increases their ability to survive in the cold. We identified an I. scapularis antifreeze glycoprotein, designated IAFGP, and demonstrated via RNAi knockdown studies the importance of IAFGP for the survival of I. scapularis ticks in a cold environment. Transfection studies also show that IAFGP increased the viability of yeast cells subjected to cold temperature. Remarkably, A. phagocytophilum induced the expression of iafgp, thereby increasing the cold tolerance and survival of I. scapularis. These data define a molecular basis for symbiosis between a human pathogenic bacterium and its arthropod vector and delineate what we believe to be a new pathway that may be targeted to alter the life cycle of this microbe and its invertebrate host.     

The value of transmandibular approach to total maxillectomy in the management of T3–T4 carcinoma of the maxillary sinus

Surgical excision of the maxilla either as a primary procedure or after radiotherapy continues to play an important role in the management of carcinoma of the maxillary sinus. A majority of these cancers are seen in T3–T4 stage. Recurrence at the infratemporal fossa has been recognized as a major cause of failure. Although the importance of inclusion of the pterygopalatine fossa in the field of excision has been recognized, there is no uniform approach for en bloc removal of the pterygopalatine fossa. Transmandibular approach has been described for purpose and practiced at the Bangalore Institute of Oncology for the past 8 years with success. This paper presents the technique used, its benefits and the results obtained.     

Foveal neovascularisation in diabetic retinopathy: case report and review of literature

To report a rare case of unilateral foveal neovascularisation in an asymptomatic patient with 15-year history of insulin-dependent diabetes mellitus and bilateral proliferative diabetic retinopathy and diabetic macular edema. Fundus fluorescein angiography and optical coherence tomography scan confirmed the presence of foveal neovascularisation. There was complete regression of the foveal neovascularisation after pan retinal laser photocoagulation. We review the literature on foveal neovascularisation in diabetic retinopathy and propose a possible pathogenic mechanism for development of foveal neovascularisation in diabetic retinopathy and the reason for the response to pan retinal laser photocoagulation.     

Acetyl salicyclic acid (aspirin) improves synthesis of maspin and lowers incidence of metastasis in breast cancer patients

Maspin, a 42 kDa protein produced in normal breast cells, has been shown to inhibit the invasion and metastasis of breast cancer in an animal model. Ingestion of acetylsalicylic acid (aspirin) by breast cancer patients has been reported to restore the systemic synthesis of maspin through the stimulation of systemic nitric oxide production. Studies were carried out to determine the effect of aspirin on the incidence of breast cancer metastasis, which is reported to occur in 50% of patients who have previously received chemotherapy, radiation, and/or surgery. Thirty‐five female patients (aged 41–65 years) with breast cancer who had previously received these therapies took one 75 mg/70 kg body weight enteric‐coated aspirin tablet every 24 h, after an adequate meal, for 3 years. Their plasma nitric oxide and maspin levels were measured. The occurrence of metastasis was ascertained monthly by a qualified oncologist, and confirmed, if necessary, by biopsy. Daily ingestion of aspirin by participants resulted in an increase in maspin levels from 0.95 ± 0.04 to 4.63 ± 0.05 nM after 24 h. These levels were maintained for 3 years. These studies suggest that daily ingestion of aspirin might significantly reduce the incidence of breast cancer metastasis in patients who have previously received anticancer therapies. (Cancer Sci 2010)     

Diagnosis of post‐transplant lymphoproliferative disorder in solid organ transplant recipients – BCSH and BTS Guidelines

A joint working group established by the Haemato‐oncology subgroup of the British Committee for Standards in Haematology (BCSH) and the British Transplantation Society (BTS) has reviewed the available literature and made recommendations for the diagnosis and management of post‐transplant lymphoproliferative disorder (PTLD) in adult recipients of solid organ transplants. This review details the risk factors predisposing to development, initial features and diagnosis. It is important that the risk of developing PTLD is considered when using post transplant immunosuppression and that the appropriate investigations are carried out when there are suspicions of the diagnosis. These must include tissue for histology and computed tomography scan to assess the extent of disease. These recommendations have been made primarily for adult patients, there have been some comments made with regard to paediatric practice.     

Neutralization of haemorrhagic activity of viper venoms by 1-(3-dimethylaminopropyl)-1-(4-fluorophenyl)-3-oxo-1,3-dihydroisobenzofuran-5-carbonitrile

Viper envenomation undeniably induces brutal local manifestations such as haemorrhage, oedema and necrosis involving massive degradation of extracellular matrix at the bitten region and many a times results in dangerous systemic haemorrhage including pulmonary shock. Snake venom metalloproteases (SVMPs) are being considered to be the primary culprits for the venom-induced haemorrhage. As a consequence, the venom researchers and medical practitioners are in deliberate quest of SVMP inhibitors. In this study, we evaluated the inhibitory effect of 1-(3-dimethylaminopropyl)-1-(4-fluorophenyl)-3-oxo-1,3-dihydroisobenzofuran-5-carbonitrile (DFD) on viper venom-induced haemorrhagic and PLA(2) activities. DFD effectively neutralized the haemorrhagic activity of the medically important viper venoms such as Echis carinatus, Echis ocelatus, Echis carinatus sochureki, Echis carinatus leakeyi and Crotalus atrox in a dose-dependent manner. The histological examinations revealed that the compound DFD effectively neutralizes the basement membrane degradation, and accumulation of inflammatory leucocytes at the site of Echis carinatus venom injection further confirms the inhibition of haemorrhagic activity. In addition, DFD dose dependently inhibited the PLA(2) activities of Crotalus atrox and E. c. leakeyi venoms. According to the docking studies, DFD binds to hydrophobic pocket of SVMP with the ki of 19.26 × 10(-9) (kcal/mol) without chelating Zn(2+) in the active site. It is concluded that the clinically approved inhibitors of haemorrhagins could be used as a potent first-aid agent in snakebite management. Furthermore, a high degree of structural and functional homology between SVMPs and their relatives, the MMPs, suggests that DFD analogues may find immense value in the regulation of multifactorial pathological conditions like inflammation, cancer and wound healing.     

Antimicrobial properties of a non-toxic glycoprotein (WSG) from Withania somnifera (Ashwagandha)

A monomeric glycoprotein with a molecular mass of 28 kDa in SDS-PAGE was isolated from the Withania somnifera root tubers. The protein designated WSG (Withania somnifera glycoprotein) demonstrated potent antimicrobial activity against the phytopathogenic fungi and bacteria tested. Antifungal effect has been demonstrated in that WSG exerts a fungistastic effect by inhibiting spore germination and hyphal growth in the tested fungi. WSG showed potent antifungal activity against Aspergillus flavus, Fusarium oxysporum, F. verticilloides and antibacterial activity against Clvibacter michiganensis subsp. michiganensis. WSG is an acidic, non-toxic (trypsin-chymotrypsin) protease inhibitor. These results encourage further studies of WSG as a potential therapeutic agent for its antifungal activity.     

Late thrombosis of drug-eluting stents: a meta-analysis of randomized clinical trials

Purpose

Drug-eluting stents are commonly used for percutaneous coronary intervention. Despite excellent clinical efficacy, the association between drug-eluting stents and the risk for late thrombosis remains imprecisely defined.

Methods

We performed a meta-analysis on 14 contemporary clinical trials that randomized 6675 patients to drug-eluting stents (paclitaxel or sirolimus) compared with bare metal stents. Eight of these trials have reported more than a year of clinical follow-up.

Results

The incidence of very late thrombosis (>1 year after the index procedure) was 5.0 events per 1000 drug-eluting stent patients, with no events in bare metal stent patients (risk ratio [RR] = 5.02, 95% confidence interval [CI], 1.29 to 19.52, P = .02). Among sirolimus trials, the incidence of very late thrombosis was 3.6 events per 1000 sirolimus stent patients, with no events in bare metal stent patients (RR = 3.99, 95% CI, .45 to 35.62, P = .22). The median time of late sirolimus stent thrombosis was 15.5 months, whereas with bare metal stents it was 4 months. Among paclitaxel trials, the incidence of very late thrombosis was 5.9 events per 1000 paclitaxel stent patients, with no events in bare metal stent patients (RR = 5.72, 95% CI, 1.08 to 32.45, P = .049). The median time of late paclitaxel stent thrombosis was 18 months, whereas it was 3.5 months in bare metal stent patients.

Conclusions

Although the incidence of very late stent thrombosis more than 1 year after coronary revascularization is low, drug-eluting stents appear to increase the risk for late thrombosis. Although more of this risk was seen with paclitaxel stents, it remains possible that sirolimus stents similarly increase the risk for late thrombosis compared with bare metal stents.     

The role of insulin dependent NO synthesis in the impaired production of maspin in human breast cancer

Purpose: The synthesis of maspin, a protein with various anti-breast cancer properties has been reported to be produced in normal breast tissue but not in breast cancer cells. We investigated the role of insulin receptors and their upregulation by prostaglandin E₁ in vitro for the stimulation of NO synthesis by the hormone, and its consequence on maspin production in normal neutrophils and malignant cells in breast cancer. Methods: Maspin and NO were determined by ELISA and methemoglobin method, respectively. Results: The treatment of neutrophils and malignant breast cancer cells with prostaglandin E₁ resulted in partial restoration of the impaired receptor numbers, and resulted in partial normalization of NO and maspin production in these cells compared to normal counterparts. It was not feasible to stimulate NO synthesis to normal ranges by the upregulation of receptor number due to intrinsic decrease of insulin receptors in breast cancer cells. However, aspirin, which was found to stimulate NO synthesis to normal ranges, normalized maspin production in these cells in breast cancer. Conclusion: The impaired maspin production was found to be the consequence of impaired insulin induced NO production in breast cancer due to the decrease of insulin receptor binding. Restoration of NO production by aspirin can be useful for the restoration of maspin production in breast cancer.