Acetabular and Femoral Component Positioning Using Direct Anterior Approach Versus Posterior Approach in Total Hip Arthroplasty

PurposeDirect anterior approach (DAA) has recently become popular in total hip arthroplasty (THA). However, irrespective of the surgical approach used, component malposition is an important factor affecting function and complications after THA. This study aims to compare component positioning on the femoral and acetabular side between DAA and posterior approach (PA) to the hip joint. We hypothesized that the two approaches are similar in terms of component positioning.MethodsWe prospectively studied 50 patients, matched according to age, sex, and body mass index, undergoing THA, divided non-randomly into 2 groups. Group 1 comprised 25 patients (35 hips) undergoing THA using DAA and group 2 comprised 25 patients (25 hips) undergoing THA using PA. Ten patients from group 1 had simultaneous bilateral THA. Radiological parameters studied were acetabular inclination (AI), coronal femoral stem alignment (CFA), leg length difference (LLD), acetabular cup version (AV), and femoral stem version (FV).ResultsThere was no significant difference in AI, CFA, LLD, AV, and FV between the two groups. Excellent to good inter and intra-observer reliability expressed in terms of intraclass correlation coefficient (ICC) was noted for all the radiographic measurements.ConclusionBoth DAA and PA for THA achieve comparable radiological component positioning. DAA may not provide any advantage over PA in terms of positioning of the prosthesis.Level of EvidenceLevel II, non-randomized comparative study.     

Are vaporizers a lower-risk alternative to smoking cannabis?

Cannabis use is associated with various adverse physical and mental health outcomes as well as increased risk of motor vehicle collision. Many organizations and the “Lower-Risk Cannabis Use Guidelines” have recommended to use cannabis vaporizers instead of smoking to reduce the associated health risk. This commentary draws attention to the present evidence regarding harm reduction potential of cannabis vaping. Cannabis vaporizer use can reduce the emission of carbon monoxide, chronic respiratory symptoms, and exposure to several toxins while producing similar subjective effects and blood THC concentration compared with smoking cannabis, holding potential for harm reduction among habitual cannabis smokers. However, new cannabis users, regardless of method of administration of cannabis, may experience intense subjective effects and cognitive impairment with increased susceptibility to dependence. Hence, policy makers should consider limiting access to cannabis among young people and adopting strategies to reduce impaired driving under influence of cannabis. Future research should focus on impact of switching from cannabis smoking to dried herb vaping using cannabis vaporizers among chronic cannabis smokers, and long-term outcomes of medical cannabis vaping, and further explore association of vaping-associated lung injury with THC-containing e-liquids.     

Interleukin-10 gene transfer inhibits murine mammary tumors and elevates nitric oxide

Transfection of cDNA for IL-10 into line 66.1 murine mammary tumor cells results in marked suppression of tumor growth and metastasis. Others have reported that nitric oxide has potent antitumor activity and IL-10 is known to regulate the inducible isoform of nitric oxide synthase (iNOS) expressed in macrophages. We identified nitric oxide production in mammary tumors as indicated by electron paramagnetic resonance detection of nitric oxide-hemoglobin (NO-Hb). IL-10 expression resulted in elevated levels of NO-Hb in mammary tumors. Immunohistochemical examination of mammary tumors for iNOS protein revealed few positively staining cells in parental or control neo-transfected tumors but strong iNOS staining in all IL-10 transfected tumors, consistent with the NO-Hb data. To determine if mammary epithelial tumor cells themselves, express nitric oxide synthase activity, cultured tumor cells were treated with pro-inflammatory cytokines and nitrite accumulation was assessed in the conditioned medium. All IL-10 producing cell lines accumulated uM concentrations of nitrite in response to short term (24 hr) cytokine stimulation. Cells not expressing IL-10 (parental and neo-transfectants) accumulated no nitrite under similar culture conditions. After longer stimulation (48 hr), parental and 66-neo cells accumulated lower amounts of nitrite. IL-10 gene transfer is associated with increased iNOS protein expression and enzymatic activity detected both in vitro<0R> and in vivo<0R>. Our findings suggest that the antimetastatic and antitumor activity of IL-10 is related to enhanced production of nitric oxide. Int. J. Cancer 76:713–719, 1998.© 1998 Wiley-Liss, Inc.     

Pachypodol, a flavonol from the leaves of Calycopteris floribunda, inhibits the growth of CaCo 2 colon cancer cell line in vitro

Calycopteris floribunda Lam., commonly known as 'goichia lata or goache lata', is a large climbing woody shrub from Bangladesh, and well distributed in a number of other south-east Asian countries. Traditionally, C. floribunda has been used in colic, as an antihelminthic, astringent and carminative, and for the treatment of diarrhoea, dysentery, jaundice and malaria in many countries including Bangladesh. Pachypodol (5,4'-dihydroxy-3,7,3'-trimethoxyflavone) has been isolated from the leaves of C. floribunda by repeated column chromatography on silica gel, and the structure confirmed by spectroscopic means. While the general toxicity of pachypodol was determined by the brine shrimp lethality assay, the cytotoxic potential of this flavonoid has been evaluated by the Promega's CellTiter 96 Non-Radioactive Cell Proliferation Assay using the CaCo-2 colon cancer cell line (IC(50) = 185.6 microM). A summary of the biological activities of pachypodol reported to date is also presented.     

Extensive metastatic renal cell carcinoma presenting as facial nerve palsy.

Metastatic lesions of the parotid gland are well described in the literature. Metastatic spread to the parotid from renal cell carcinoma is rare. We present the only reported case of facial nerve palsy caused by a metastasis to the parotid from a renal cell carcinoma.     

Neurofibrosarcoma in the nasal cavity

A nine month old male child presented with a swelling protruding from the right nasal cavity for two months. Other symptoms were mild breathlessness during suckling and blood stained nasal discharge. CT Scan sshowed a mass arising from the lasteral wall of the right nasal cavity with mild erosion of the adjacent bones. The tumor was excised with wide margin through a lateral rhinotomy approach under general anaesthesia. In histopathological examination it was found to be a low grade neurofibrosarcoma. The child recovered well and is free from any recurrence till the time of reporting.     

Paraganglioma of external auditory canal

In the ear, paragangliomas are commonly found in the tympanic cavity or in juglar bulb. We, here, present a case of paraganglioma originating from the external auditory canal as it has not been reported in the world literature. The clinico-pathologic features of such a case has been described.     

Cytoglobin has potent superoxide dismutase function

Cytoglobin (Cygb) was discovered as a novel type of globin that is expressed in mammals; however, its functions remain uncertain. While Cygb protects against oxidant stress, the basis for this is unclear, and the effect of Cygb on superoxide metabolism is unknown. From dose-dependent studies of the effect of Cygb on superoxide catabolism, we identify that Cygb has potent superoxide dismutase (SOD) function. Initial assays using cytochrome c showed that Cygb exhibits a high rate of superoxide dismutation on the order of 10⁸ M⁻¹ ⋅ s⁻¹. Spin-trapping studies also demonstrated that the rate of Cygb-mediated superoxide dismutation (1.6 × 10⁸ M⁻¹ ⋅ s⁻¹) was only ∼10-fold less than Cu,Zn-SOD. Stopped-flow experiments confirmed that Cygb rapidly dismutates superoxide with rates within an order of magnitude of Cu,Zn-SOD or Mn-SOD. The SOD function of Cygb was inhibited by cyanide and CO that coordinate to Fe³⁺-Cygb and Fe²⁺-Cygb, respectively, suggesting that dismutation involves iron redox cycling, and this was confirmed by spectrophotometric titrations. In control smooth-muscle cells and cells with siRNA-mediated Cygb knockdown subjected to extracellular superoxide stress from xanthine/xanthine oxidase or intracellular superoxide stress triggered by the uncoupler, menadione, Cygb had a prominent role in superoxide metabolism and protected against superoxide-mediated death. Similar experiments in vessels showed higher levels of superoxide in Cygb^−/− mice than wild type. Thus, Cygb has potent SOD function and can rapidly dismutate superoxide in cells, conferring protection against oxidant injury. In view of its ubiquitous cellular expression at micromolar concentrations in smooth-muscle and other cells, Cygb can play an important role in cellular superoxide metabolism.

Over the last decade, cytoglobin (Cygb) was discovered as a fourth globin type expressed in mammals, predominantly in fibroblasts, smooth muscle, and related cell types in different organs and tissues (1–3). Since Cygb has structural similarity to myoglobin (Mb) and hemoglobin (Hb) and is up-regulated in tissues upon hypoxia (4), it has been suggested that Cygb may play a role in storing O₂, facilitating O₂ diffusion and sensing, NO dioxygenation, or protecting against oxidative stress (1, 4–6). The Cygb concentration in cells is ∼1 to 5 µM (5–7), which is much less than Hb concentration in red blood cells (∼8 mM) and Mb in cardiac and striated muscle (hundreds of micromolar to millimolar), resulting in a much lower capacity for O₂ storage or ability to facilitate O₂ diffusion. Thus, major questions remain about the function of Cygb and why there is a need for this additional globin.There is an emerging body of evidence which suggests that Cygb may provide protection from oxidative cellular injury, possibly due to its ability to scavenge or catabolize reactive oxygen species (ROS) (8–10). Overexpression of Cygb has been shown to decrease the levels of chemically induced ROS and to provide protection from pro-oxidant injury. Conversely, down-regulation of Cygb sensitizes cells to the damaging effects of oxidant exposure and to oxidative DNA damage (8–10). Cells and organs lacking Cygb are more prone to radiation-induced injury as well as fibrosis and inflammatory disease (8).While Cygb is reported to protect against oxidative stress, the mechanistic basis for this antioxidative efficacy has remained unclear. To date, the precise effect of Cygb on superoxide (O₂^•−) metabolism is unknown. We hypothesize that Cygb can function to degrade O₂^•− and is a potent superoxide dismutase (SOD). Therefore, we perform studies to determine the dose-dependent effect of Cygb on the O₂^•− generated from xanthine (X) and xanthine oxidase (XO).We demonstrate that Cygb has potent SOD function. The rate of its O₂^•− dismutation measured from the concentration-dependent reaction with cytochrome c (cyt c) or the spin trap 5-(diisopropoxy-phosphoryl)-5-methyl-1-pyrroline-N-oxide (DIPPMPO) or direct stopped-flow measurements is determined to be within an order of magnitude of that of copper-zinc SOD (Cu,Zn-SOD) and manganese SOD (Mn-SOD). In smooth muscle cells (SMCs) subjected to oxidative stress, we also show that Cygb plays a major role in the metabolism of O₂^•− and protects the cells against O₂^•−-mediated death.     

Correction: Strongly coupled Mn3O4-porous organic polymer hybrid: a robust,durable and potential nanocatalyst for alcohol oxidation reactions

Correction for ‘Strongly coupled Mn₃O₄-porous organic polymer hybrid: a robust, durable and potential nanocatalyst for alcohol oxidation reactions’ by Karnekanti Dhanalaxmi et al., RSC Adv., 2016, 6, 36728–36735, DOI: 10.1039/C6RA07200C.

The authors regret that, in the original publication of this article, some author affiliation details were missing.An extra affiliation has been added for the authors Karnekanti Dhanalaxmi and John Mondal. Full details are provided in the affiliations section of this document.The Royal Society of Chemistry apologises for these errors and any consequent inconvenience to authors and readers.     

Molecular Characterization of the SHV-11 β-Lactamase of Shigella dysenteriae

A beta-lactamase with an M(r) of 29,000 and a pI of 7.6 was partially purified from a clinical isolate of Shigella dysenteriae. The bla gene encoded the SHV-11 enzyme carrying the substitution Leu-->Gln at position 35 and was linked to a strong promoter. This variant, unlike the prototype SHV-1 enzyme, hydrolyzed oxacillin, cloxacillin, and oxyiminocephalosporins such as cefotaxime.