LRRC15 mediates an accessory interaction with the SARS-CoV-2 spike protein.

The interactions between Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) and human host factors enable the virus to propagate infections that lead to Coronavirus Disease 2019 (COVID-19). The spike protein is the largest structural component of the virus and mediates interactions essential for infection, including with the primary angiotensin-converting enzyme 2 (ACE2) receptor. We performed two independent cell-based systematic screens to determine whether there are additional proteins by which the spike protein of SARS-CoV-2 can interact with human cells. We discovered that in addition to ACE2, expression of LRRC15 also causes spike protein binding. This interaction is distinct from other known spike attachment mechanisms such as heparan sulfates or lectin receptors. Measurements of orthologous coronavirus spike proteins implied the interaction was functionally restricted to SARS-CoV-2 by accessibility. We localized the interaction to the C-terminus of the S1 domain and showed that LRRC15 shares recognition of the ACE2 receptor binding domain. From analyzing proteomics and single-cell transcriptomics, we identify LRRC15 expression as being common in human lung vasculature cells and fibroblasts. Levels of LRRC15 were greatly elevated by inflammatory signals in the lungs of COVID-19 patients. Although infection assays demonstrated that LRRC15 alone is not sufficient to permit viral entry, we present evidence that it can modulate infection of human cells. This unexpected interaction merits further investigation to determine how SARS-CoV-2 exploits host LRRC15 and whether it could account for any of the distinctive features of COVID-19.

Coxiella burnetii inhibits host immunity by a protein phosphatase adapted from glycolysis.

Coxiella burnetii is a bacterial pathogen that replicates within host cells by establishing a membrane-bound niche called the Coxiella-containing vacuole. Biogenesis of this compartment requires effectors of its Dot/Icm type IV secretion system. A large cohort of such effectors has been identified, but the function of most of them remain elusive. Here, by a cell-based functional screening, we identified the effector Cbu0513 (designated as CinF) as an inhibitor of NF-κB signaling. CinF is highly similar to a fructose-1,6-bisphosphate (FBP) aldolase/phosphatase present in diverse bacteria. Further study reveals that unlike its ortholog from Sulfolobus tokodaii, CinF does not exhibit FBP phosphatase activity. Instead, it functions as a protein phosphatase that specifically dephosphorylates and stabilizes IκBα. The IκBα phosphatase activity is essential for the role of CinF in C. burnetii virulence. Our results establish that C. burnetii utilizes a protein adapted from sugar metabolism to subvert host immunity.

Phenotype-Based Threat Assessment.

Bacterial pathogen identification, which is critical for human health, has historically relied on culturing organisms from clinical specimens. More recently, the application of machine learning (ML) to whole-genome sequences (WGSs) has facilitated pathogen identification. However, relying solely on genetic information to identify emerging or new pathogens is fundamentally constrained, especially if novel virulence factors exist. In addition, even WGSs with ML pipelines are unable to discern phenotypes associated with cryptic genetic loci linked to virulence. Here, we set out to determine if ML using phenotypic hallmarks of pathogenesis could assess potential pathogenic threat without using any sequence-based analysis. This approach successfully classified potential pathogenetic threat associated with previously machine-observed and unobserved bacteria with 99% and 85% accuracy, respectively. This work establishes a phenotype-based pipeline for potential pathogenic threat assessment, which we term PathEngine, and offers strategies for the identification of bacterial pathogens.

Modulation of innate immune signaling by a Coxiella burnetii eukaryotic-like effector protein.

The Q fever agent Coxiella burnetii uses a defect in organelle trafficking/intracellular multiplication (Dot/Icm) type 4b secretion system (T4SS) to silence the host innate immune response during infection. By investigating C. burnetii effector proteins containing eukaryotic-like domains, here we identify NopA (nucleolar protein A), which displays four regulator of chromosome condensation (RCC) repeats, homologous to those found in the eukaryotic Ras-related nuclear protein (Ran) guanine nucleotide exchange factor (GEF) RCC1. Accordingly, NopA is found associated with the chromatin nuclear fraction of cells and uses the RCC-like domain to interact with Ran. Interestingly, NopA triggers an accumulation of Ran-GTP, which accumulates at nucleoli of transfected or infected cells, thus perturbing the nuclear import of transcription factors of the innate immune signaling pathway. Accordingly, qRT-PCR analysis on a panel of cytokines shows that cells exposed to the C. burnetii nopA::Tn or a Dot/Icm-defective dotA::Tn mutant strain present a functional innate immune response, as opposed to cells exposed to wild-type C. burnetii or the corresponding nopA complemented strain. Thus, NopA is an important regulator of the innate immune response allowing Coxiella to behave as a stealth pathogen.

Differential airway remodeling changes were observed in patients with asthma COPD overlap compared to patients with asthma and COPD alone.

Management of patients with asthma COPD overlap (ACO) is clinically challenging due to insufficient evidence of pathological changes in these patients. In this cross-sectional study, we evaluated airway remodeling in endobronchial biopsies from a total of 90 subjects, which included 12 ACO, 14 patients with asthma, 12 COPD exsmokers (ES), 11 current smokers (CS), 28 healthy controls (HC), and 13 normal lung function smokers (NLFS). Tissue was stained with Masson's trichrome. Epithelium, goblet cells, reticular basement membrane (RBM), cellularity, lamina propria (LP), and smooth muscle (SM) changes were measured using Image-Pro Plus v7 software. Differential airway remodeling pattern was seen in patients with ACO. A limited change was noted in the ACO epithelium compared with other pathological groups. RBM was substantially thicker in patients with ACO than in HC (P < 0.0002) and tended to be thicker than in patients with asthma and NLFS. The total RBM cells were higher in ACO than in the HC (P < 0.0001), COPD-CS (P = 0.0559), -ES (P = 0.0345), and NLFS (P < 0.0002), but did not differ from patients with asthma. Goblet cells were higher in the ACO than in the HC (P = 0.0028) and COPD-ES (P = 0.0081). The total LP cells in ACO appeared to be higher than in HC, COPD-CS, and NLFS but appeared to be lower than in patients with asthma. Finally, SM area was significantly lower in the ACO than in patients with asthma (P = 0.001), COPD-CS (=0.0290), and NLFS (P = 0.0011). This first comprehensive study suggests that patients with ACO had distinguishable tissue remodeling that appeared to be more severe than patients with asthma and COPD. This study will help in informed decision-making for better patient management in clinical practice.

Early versus delayed defunctioning ileostomy closure after low anterior resection for rectal cancer: a meta-analysis and trial sequential analysis of safety and functional outcomes.

PURPOSE: We performed a systematic review and meta-analysis with trial sequential analysis (TSA) to answer whether early closure of defunctioning ileostomy may be suitable after low anterior resection. METHODS: MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials were searched, up to October 2021, for RCTs comparing early closure (EC ≤ 30 days) and delayed closure (DC ≥ 60 days) of defunctioning ileostomy. The risk ratio (RR) with 95% CI was calculated for dichotomous variables and the mean difference (MD) with 95% CI for continuous variables. The GRADE methodology was implemented for assessing Quality of Evidence (QoE). TSA was implemented to address the risk of random error associated with sparse data and/or multiple testing. RESULTS: Seven RCTs were included for quantitative synthesis. 599 patients were allocated to either EC (n = 306) or DC (n = 293). EC was associated with a higher rate of wound complications compared to DC (RR 2.56; 95% CI 1.33 to 4.93; P = 0.005; I2 = 0%, QoE High), a lower incidence of postoperative small bowel obstruction (RR 0.46; 95% CI 0.24 to 0.89; P = 0.02; I2 = 0%, QoE moderate), and a lower rate of stoma-related complications (RR 0.26; 95% CI 0.16 to 0.42; P < 0.00001; I2 = 0%, QoE moderate). The rate of minor low anterior resection syndrome (LARS) (RR 1.13; 95% CI 0.55 to 2.33; P = 0.74; I2 = 0%, QoE low) and major LARS (RR 0.80; 95% CI 0.59 to 1.09; P = 0.16; I2 = 0%, QoE low) did not differ between the two groups. TSA demonstrated inconclusive evidence with insufficient sample sizes to detect the observed effects. CONCLUSION: EC may confer some advantages compared with a DC. However, TSA advocated a cautious interpretation of the results. PROSPERO REGISTER ID: CRD42021276557.

Intratracheal Inoculation with Brucella melitensis in the Pregnant Guinea Pig Is an Improved Model for Reproductive Pathogenesis and Vaccine Studies.

Reproductive failure is the hallmark of brucellosis in animals. An uncommon but important complication in pregnant women who become acutely infected with Brucella melitensis is spontaneous pregnancy loss or vertical transmission to the fetus. Unfortunately, the mechanism behind reproductive failure is still obscure, partially due to the lack of a proper study model. Recently, it was demonstrated that intratracheal (IT) inoculation of nonpregnant guinea pigs would replicate features of clinical disease in humans. To determine if IT inoculation would induce reproductive disease, guinea pigs were infected at mid-gestation and monitored daily for fever and abortions. Fever developed between day 14 to 18 postinoculation, and by 3 weeks postinoculation, 75% of pregnant guinea pigs experienced stillbirths or spontaneous abortions mimicking natural disease. Next, to investigate the guinea pig as a model for evaluating vaccine efficacy during pregnancy, nonpregnant guinea pigs were vaccinated with S19, 16MΔvjbR + Quil-A, or 100 µl PBS + Quil-A (as control). Guinea pigs were bred and vaccinated guinea pigs were challenged at mid-gestation with B. melitensis IT inoculation and monitored for fever and abortions. Vaccination with both vaccines prevented fever and protected against abortion. Together, this study indicates that pregnant guinea pigs are an appropriate animal model to study reproductive disease and offer an improved model to evaluate the ability of vaccine candidates to protect against a serious manifestation of disease.

Chemokine Receptor 7 Is Essential for Coxiella burnetii Whole-Cell Vaccine-Induced Cellular Immunity but Dispensable for Vaccine-Mediated Protective Immunity.

BACKGROUND: Protective immunity against Coxiella burnetii infection is conferred by vaccination with virulent (PI-WCV), but not avirulent (PII-WCV) whole-cell inactivated bacterium. The only well-characterized antigenic difference between virulent and avirulent C. burnetii is they have smooth and rough lipopolysaccharide (LPS), respectively. METHODS: Mice were vaccinated with PI-WCV and PII-WCV. Humoral and cellular responses were evaluated using protein chip microarrays and ELISpots, respectively. Dendritic cell (DC) maturation after stimulation with PI-WVC and PII-WVC was evaluated using flow cytometry. Vaccine-challenge studies were performed to validate the importance of the receptor CCR7. RESULTS: Other than specific antibody response to PI-LPS, similar antibody profiles were observed but IgG titers were significantly higher after vaccination with PI-WCV. Furthermore, higher frequency of antigen-specific CD4+ T cells was detected in mice immunized with PI-WCV. PI-WCV-stimulated DCs displayed significantly higher levels of CCR7 and migratory ability to secondary lymphoid organs. Challenge-protection studies in wild-type and CCR7-deficient mice confirmed that CCR7 is critical for PI-WCV-induced cellular immunity. CONCLUSIONS: PI-WVC stimulates protective immunity to C. burnetii in mice through stimulation of migratory behavior in DCs for protective cellular immunity. Additionally, the humoral immune response to LPS is an important component of protective immunity.

Space: A Final Frontier for Vacuolar Pathogens.

There is a fundamental gap in our understanding of how a eukaryotic cell apportions the limited space within its cell membrane. Upon infection, a cell competes with intracellular pathogens for control of this same precious resource. The struggle between pathogen and host provides us with an opportunity to uncover the mechanisms regulating subcellular space by understanding how pathogens modulate vesicular traffic and membrane fusion events to create a specialized compartment for replication. By comparing several important intracellular pathogens, we review the molecular mechanisms and trafficking pathways that drive two space allocation strategies, the formation of tight and spacious pathogen-containing vacuoles. Additionally, we discuss the potential advantages of each pathogenic lifestyle, the broader implications these lifestyles might have for cellular biology and outline exciting opportunities for future investigation.

A Pulsatile Fresh Frozen Human Cadaver Circulation Model for Endovascular Training: A Trial of Face Validity.

BACKGROUND: The authors have published their design of a pulsatile fresh frozen human cadaver circulation model (PHCM) for endovascular training the face validity of the PHCM for training endovascular practitioners was subsequently assessed. METHODS: Twelve endovascular clinicians performed the same 2 procedures (catheterization of the left renal artery and left subclavian artery) on PHCM and Simbionix angiomentor virtual reality simulator (SVR). They were randomized to begin on either the PHCM or SVR. A pretrial questionnaire determined participants' endovascular experience. After training, participants rated statements relating to their experience on a numerical scale from 1 to 5, with 1 representing the strongest agreement with the statement. RESULTS: When participants were asked to compare the realism of training modalities with live patients, PHCM scored significantly higher than SVR on statements regarding "realism of vascular access" (P = 0.002), "guide-wire manipulation" (P = 0.001), and "vessel catheterization" (P = 0.004). Candidates again favored PHCM as "a valuable learning exercise" (P = 0.016) and strongly favored PHCM as a "useful training model" compared to SVR (P = 0.004). CONCLUSIONS: This is the first published trial in world literature to assess the validity of a PHCM for training endovascular practitioners. The PHCM demonstrates good face validity when compared to both real patients and the SVR model and holds exciting potential.

Evaluating the Construct Validity of a Pulsatile Fresh Frozen Human Cadaver Circulation Model for Endovascular Training.

BACKGROUND: We recently described a pulsatile fresh frozen human cadaver model (PHCM) for training endovascular practitioners. This present study aims to assess the construct validity of PHCM; its ability to differentiate between participants of varying expertise. METHODS: Twenty-three participants with varying endovascular experience (12 novice, 4 intermediate, and 7 expert) were recruited. Each attempted catheterization of the left renal artery on PHCM within 10 min under exam conditions. Performances were video recorded and scored using a validated scoring tool by 2 independent endovascular experts, blinded to performer status. Each participant was given a task-specific checklist score (TSC), global rating score (GRS), and overall procedure score (OPS). Finally, examiners were asked whether they would be happy to supervise the participant in theater, with each participant graded as "fail", "borderline," or "pass". RESULTS: All expert and intermediate participants completed the index procedure within the allotted 10 min; however, only one of the 12 novice participants achieved this (P < 0.0005). Endovascular novices had significantly lower TSC, GRS, and OPS than both intermediate participants and endovascular experts. There were no significant differences in TSC, GRS, or OPS between intermediate participants and endovascular experts. When participants were graded as "fail", "borderline," or "pass," there were significant differences between groups (P = 0.001). All of the intermediate and expert participants received a pass. Out of the 12 novice participants, 2 received a pass, 6 received a borderline, and 4 were failed. CONCLUSIONS: The PHCM demonstrates construct validity. Further work is required to determine its educational impact in endovascular training.

Aetiology of recurrent miscarriage and the role of adjuvant treatment in its management: a retrospective cohort review.

We conducted a retrospective review into the role of commonly prescribed conventional adjuvant treatments in improving live birth rates after recurrent miscarriage (RM). Data from 301 couples attending the RM clinic in two Tertiary teaching hospitals were analysed with their live birth rate following a further pregnancy and a prevalence of conditions investigated in RM being the main outcomes measured. We found that 26% of women had explained RM and 74% had unexplained RM. Adjuvant versus conservative management did not improve the live birth rates in those with unexplained RM (68.4% vs. 76.6%, respectively; p = .28). The prevalence of anti-phospholipid syndrome, inherited thrombophilia, thyroid disease, parental karyotype abnormalities and structural uterine abnormalities were 7.4%, 4.5%, 6.6%, 2.9% and 6.6%, respectively. In conclusion, empirical adjuvant treatment for the management of women with unexplained RM does not appear to offer any benefit as they have a good prognosis with early pregnancy support alone. Impact statement What is already known on this subject? Does the adjuvant treatment in the management of unexplained recurrent miscarriage (RM) improve successful pregnancy outcomes? High-quality data regarding the management and outcomes of RM is very limited, with many clinicians prescribing adjuvant treatments for unexplained RM with very little good quality evidence of their benefit or risk. What do the results of this study add? We carried out a retrospective cohort study of all patients attending a recurrent miscarriage clinic over a two-year period at specialist clinics in two tertiary referral centres to evaluate the prevalence of associated diseases, the treatments given and the outcomes in subsequent pregnancies. This study will help clinicians counsel their patients about management options in RM and help them reassure their patients that the prognosis with conservative management alone is good. This will help to avoid any unnecessary use of adjuvant treatment and its associated risks and cost. What are the implications of these findings for clinical practice and/or further research? This study demonstrates that adjuvant treatments in unexplained RM have no significant benefit on future live birth rates. Despite this finding, high quality, prospective, randomised controlled trials looking at both adverse outcomes and benefits of adjuvant treatment in RM are needed.

Screening of plant growth promotion ability among bacteria isolated from field-grown sorghum under different managements in Brazilian drylands.

Sorghum [Sorghum bicolor (L.) Moench] is a multipurpose grass cultivated in drylands due to its adaptation to drought. However the characteristics of sorghum-associated bacteria are not known in the Brazilian drylands. The aim of this study was to isolate and evaluate the plant growth promotion potential bacteria from field-grown sorghum under two irrigation and manure application levels in a Brazilian semi-arid reagion. Sorghum was irrigated with 3 or 1 mm day-1 and fertilized or not with liquid goat manure. Bacteria were obtained from surface-disinfected roots applying two nitrogen-free semi-solid media. The bacteria were evaluated for the presence of nifH gene, 16S rRNA sequences, calcium-phosphate solubilization, production of auxins and siderophores and for sorghum growth promotion. We obtained 20 out of 24 positive bacteria for nifH. The isolates were classified as in six different genera. All isolates produced auxins "in vitro", six bacteria produced siderophores and three Enterobacteriaceae solubilized calcium-phosphate. At least ten bacteria resulted in the increased total N content in the sorghum shoots, comparable to fertilization with 50 mg N plant-1 week-1 and to inoculation with Azospirillum brasilense Ab-V5. Enterobacter sp. ESA 57 was the best sorghum plant-growth promoting bacteria isolated in this study.

Identification of Coxiella burnetii CD8+ T-Cell Epitopes and Delivery by Attenuated Listeria monocytogenes as a Vaccine Vector in a C57BL/6 Mouse Model.

Coxiella burnetii is a gram-negative bacterium that causes acute and chronic Q fever. Because of the severe adverse effect of whole-cell vaccination, identification of immunodominant antigens of C. burnetii has become a major focus of Q fever vaccine development. We hypothesized that secreted C. burnetii type IV secretion system (T4SS) effectors may represent a major class of CD8+ T-cell antigens, owing to their cytosolic localization. Twenty-nine peptides were identified that elicited robust CD8+ T-cell interferon γ (IFN-γ) recall responses from mice infected with C. burnetii. Interestingly, 22 of 29 epitopes were derived from 17 T4SS-related proteins, none of which were identified as immunodominant antigens by using previous antibody-guided approaches. These epitopes were expressed in an attenuated Listeria monocytogenes vaccine strain. Immunization with recombinant L. monocytogenes vaccines induced a robust CD8+ T-cell response and conferred measurable protection against C. burnetii infection in mice. These data suggested that T4SS effectors represent an important class of C. burnetii antigens that can induce CD8+ T-cell responses. We also showed that attenuated L. monocytogenes vaccine vectors are an efficient antigen-delivery platform that can be used to induce robust protective CD8+ T-cell immune responses against C. burnetii infection.

Levels of some heavy metals in vegetables from artisanal mining sites of Dilimi River, Bukuru and Barkin Ladi North Central Nigeria: any public health concern?

Background: North Central Nigeria is the food basket of Nigeria but is also known for its artisanal mining with attendant public health consequences which is hitherto unquantified. Vegetables grown close to these mining sites may be contaminated with heavy metals. Objective: This study has estimated health risk associated with heavy metals HM (Cd, Cr, Cu, Zn, Se and Ni) in vegetables harvested inform the mining areas of Dilimi, Bukuru and Barkin Ladi by calculating the Daily intake, Target Hazard Quotient (THQ), Hazard Index (HI) and the Cancer risk (CR) for adults and children in the local population. Material and methods: Vegetable, soil, irrigation water and sediments samples were collected, digested, ashed and analyzed for HM using an Atomic Absorption Spectrometer (AAS). Results: The concentration of heavy metals in vegetables were in the order Cd < Se < Cr < Cu < Ni < Zn. There were higher HM levels in soil than vegetables samples. The daily intake of HM from vegetable consumption decreased in the following order Cd < Se < Cr < Cu < Ni < Zn. At least 62.5% of vegetable samples had THQ values > 1 in Dilimi, Bukuru and Barkin ladi (Adults) while 13% of vegetable samples had THQ values > 1 in children. The THQ of nickel ranged from 0.38-2.73 and 0.21-1.53 in adults and children respectively. The bio-concentration factor ranged from 0.026-7.52, 0.01-0.36 and 0.0011-1.23 in Dilimi, Bukuru and Barkin Ladi respectively for all the studied heavy metals. The cancer risk values ranged from 0.011-0.04 and 0.00066-0.02 across all the studied areas for adults and children respectively. HI values for adults were all >1 and also the total cancer risk was above the acceptable range of 10-4. Conclusion: Since THQ is > 1 in most of the samples, HI values > 1 for adults in all the vegetable and cancer risk above the acceptable limit consumption of vegetables from the study areas is not free of risk.

Methylmercury Induced Neurotoxicity and the Influence of Selenium in the Brains of Adult Zebrafish (Danio rerio).

The neurotoxicity of methylmercury (MeHg) is well characterised, and the ameliorating effects of selenium have been described. However, little is known about the molecular mechanisms behind this contaminant-nutrient interaction. We investigated the influence of selenium (as selenomethionine, SeMet) and MeHg on mercury accumulation and protein expression in the brain of adult zebrafish (Danio rerio). Fish were fed diets containing elevated levels of MeHg and/or SeMet in a 2 × 2 full factorial design for eight weeks. Mercury concentrations were highest in the brain tissue of MeHg-exposed fish compared to the controls, whereas lower levels of mercury were found in the brain of zebrafish fed both MeHg and SeMet compared with the fish fed MeHg alone. The expression levels of proteins associated with gap junction signalling, oxidative phosphorylation, and mitochondrial dysfunction were significantly (p < 0.05) altered in the brain of zebrafish after exposure to MeHg and SeMet alone or in combination. Analysis of upstream regulators indicated that these changes were linked to the mammalian target of rapamycin (mTOR) pathways, which were activated by MeHg and inhibited by SeMet, possibly through a reactive oxygen species mediated differential activation of RICTOR, the rapamycin-insensitive binding partner of mTOR.

The Type IV Secretion System Effector Protein CirA Stimulates the GTPase Activity of RhoA and Is Required for Virulence in a Mouse Model of Coxiella burnetii Infection.

Coxiella burnetii, the etiological agent of Q fever in humans, is an intracellular pathogen that replicates in an acidified parasitophorous vacuole derived from host lysosomes. Generation of this replicative compartment requires effectors delivered into the host cell by the Dot/Icm type IVb secretion system. Several effectors crucial for C. burnetii intracellular replication have been identified, but the host pathways coopted by these essential effectors are poorly defined, and very little is known about how spacious vacuoles are formed and maintained. Here we demonstrate that the essential type IVb effector, CirA, stimulates GTPase activity of RhoA. Overexpression of CirA in mammalian cells results in cell rounding and stress fiber disruption, a phenotype that is rescued by overexpression of wild-type or constitutively active RhoA. Unlike other effector proteins that subvert Rho GTPases to modulate uptake, CirA is the first effector identified that is dispensable for uptake and instead recruits Rho GTPase to promote biogenesis of the bacterial vacuole. Collectively our results highlight the importance of CirA in coopting host Rho GTPases for establishment of Coxiella burnetii infection and virulence in mammalian cell culture and mouse models of infection.

Systematic review with meta-analysis of studies comparing primary duct closure and T-tube drainage after laparoscopic common bile duct exploration for choledocholithiasis.

BACKGROUND: With advances in laparoscopic instrumentation and acquisition of advanced laparoscopic skills, laparoscopic common bile duct exploration (LCBDE) is technically feasible and increasingly practiced by surgeons worldwide. Traditional practice of suturing the dochotomy with T-tube drainage may be associated with T-tube-related complications. Primary duct closure (PDC) without a T-tube has been proposed as an alternative to T-tube placement (TTD) after LCBDE. The aim of this meta-analysis was to evaluate the safety and effectiveness of PDC when compared to TTD after LCBDE for choledocholithiasis. METHODS: A systematic literature search was performed using PubMed, EMBASE, MEDLINE, Google Scholar, and the Cochrane Central Register of Controlled Trials databases for studies comparing primary duct closure and T-tube drainage. Studies were reviewed for the primary outcome measures: overall postoperative complications, postoperative biliary-specific complications, re-interventions, and postoperative hospital stay. Secondary outcomes assessed were: operating time, median hospital expenses, and general complications. RESULTS: Sixteen studies comparing PDC and TTD qualified for inclusion in our meta-analysis, with a total of 1770 patients. PDC showed significantly better results when compared to TTD in terms of postoperative biliary peritonitis (OR 0.22, 95% CI 0.06-0.76, P = 0.02), operating time (WMD, -22.27, 95% CI -33.26 to -11.28, P < 0.00001), postoperative hospital stay (WMD, -3.22; 95% CI -4.52 to -1.92, P < 0.00001), and median hospital expenses (SMD, -1.37, 95% CI -1.96 to -0.77, P < 0.00001). Postoperative hospital stay was significantly decreased in the primary duct closure with internal biliary drainage (PDC + BD) group when compared to TTD group (WMD, -2.68; 95% CI -3.23 to -2.13, P < 0.00001). CONCLUSIONS: This comprehensive meta-analysis demonstrates that PDC after LCBDE is feasible and associated with fewer complications than TTD. Based on these results, primary duct closure may be considered as the optimal procedure for dochotomy closure after LCBDE.

Determination of patient set-up error and optimal treatment margin for intensity modulated radiotherapy using image guidance system.

PURPOSE: The geometrical uncertainties in the patient positioning during intensity modulated radiotherapy (IMRT) are crucial as there is potential to underdose the tumor and overdose the nearby critical structures. Image guided techniques provide a solution to assess the patient set-up uncertainties and help determine the optimal planning target volume (PTV) margin to the clinical tumor volume (CTV). METHODS: A retrospective study was conducted to evaluate patient set-up errors along the three translational directions at different treatment sites such as the brain, the head and neck (H&N) and the prostate. A total of 60 patients' set-up error data was analysed to evaluate the systematic and random errors and the optimal CTV-PTV margin. RESULTS: For brain and H&N sites, more than 90, 80 and about 100% of the total image acquisitions were less than 3 mm in lateral, longitudinal and vertical directions respectively. For the prostate cases, the frequency of patient set-up error to be less than 3 mm were 79.7, 75.6 and 80% in lateral, longitudinal and vertical directions respectively. About 0.6% had more than 7 mm error in the lateral and longitudinal directions for the prostate site. CTV-PTV margin of 3.4, 3.4 and 1.9 mm for brain cases, 3.5, 3 and 1.8 mm for H&N cases and 5, 4.6 and 4.5 mm for the prostate cases in the lateral, longitudinal and vertical directions respectively were determined. CONCLUSION: Image guidance is an effective method to evaluate the accuracy of IMRT treatment delivery. The optimal CTV-PTV margin can be determined to ensure adequate dose to CTV, specific to the site.

Heavy metals hazards from Nigerian spices.

BACKGROUND: Natural spices are commonly used by the people in Nigeria. They may be easily contaminated with heavy metals when they are dried and then pose a health risk for the consumers. OBJECTIVE: The aim of this study was to determine the levels of heavy metals in some commonly consumed natural spices namely Prosopis Africana, Xylopia aethiopica, Piper gineense, Monodora myristica, Monodora tenuifolia and Capsicum frutescens sold in the local markets of Awka, Anambra state, South East Nigeria to estimate the potential health risk. RESULTS: The range of heavy metal concentration was in the order: Zn (14.09 - 161.04) > Fe (28.15 - 134.59) > Pb (2.61 - 8.97) > Cr (0.001 - 3.81) > Co (0.28 - 3.07) > Ni (0.34 - 2.89). Pb, Fe and Zn exceeded the maximum allowable concentrations for spices. The Target Hazard Quotient (THQ) of the spices varied from 0.06-0.5. Estimated daily intakes (EDI) were all below the tolerable daily intake (TDI). The lead levels in Prosopis africana, Xylopia aethiopica, Piper gineense, Monodora myristica and Capsicum frutescens which are 8-30 times higher than the WHO/FAO permissible limit of 0.3 mg/kg. CONCLUSIONS: Lead contamination of spices sold in Awka (south east Nigeria) may add to the body burden of lead. A good quality control for herbal food is important in order to protect consumers from contamination. KEY WORDS: food products, spices, potential toxic metals, risk assessment, public health.