Functional analysis of the apple fruit microbiome based on shotgun metagenomic sequencing of conventional and organic orchard samples

Fruits harbour abundant and diverse microbial communities that protect them from post-harvest pathogens. Identification of functional traits associated with a given microbiota can provide a better understanding of their potential influence. Here, we focused on the epiphytic microbiome of apple fruit. We suggest that shotgun metagenomic data can indicate specific functions carried out by different groups and provide information on their potential impact. Samples were collected from the surface of 'Golden Delicious' apples from four orchards that differ in their geographic location and management practice. Approximately 1 million metagenes were predicted based on a high-quality assembly. Functional profiling of the microbiome of fruits from orchards differing in their management practice revealed a functional shift in the microbiota. The organic orchard microbiome was enriched in pathways involved in plant defence activities; the conventional orchard microbiome was enriched in pathways related to the synthesis of antibiotics. The functional significance of the variations was explored using microbial network modelling algorithms to reveal the metabolic role of specific phylogenetic groups. The analysis identified several associations supported by other published studies. For example, the analysis revealed the nutritional dependencies of the Capnodiales group, including the Alternaria pathogen, on aromatic compounds.

Reevaluation of ethylene role in Arabidopsis cauline leaf abscission induced by water stress and rewatering

It was previously reported that cauline leaf abscission in Arabidopsis is induced by a cycle of water stress and rewatering, which is regulated by the complex of INFLORESCENCE DEFICIENT IN ABSCISSION (IDA), HAESA (HAE), and HAESA-LIKE2 (HSL2) kinases. However, the involvement of ethylene in this process was ruled out. Because this conclusion contradicts the well-established role of ethylene in organ abscission induced by a cycle of water stress and rewatering, our present study was aimed to reevaluate the possible involvement of ethylene in this process. For this purpose, we examined the endogenous ethylene production during water stress and following rewatering, as well as the effects of exogenous ethylene and 1-methylcyclopropene (1-MCP), on cauline leaf abscission of Arabidopsis wild type. Additionally, we examined whether this stress induces cauline leaf abscission in ethylene-insensitive Arabidopsis mutants. The results of the present study demonstrated that ethylene production rates increased significantly in cauline leaves at 4 h after rewatering of stressed plants and remained high for at least 24 h in plants water-stressed to 40 and 30% of system weight. Ethylene treatment applied to well-watered plants induced cauline leaf abscission, which was inhibited by 1-MCP. Cauline leaf abscission was also inhibited by 1-MCP applied during a cycle of water stress and rewatering. Finally, no abscission occurred in two ethylene-insensitive mutants, ein2-1 and ein2-5, following a cycle of water stress and rewatering. Taken together, these results clearly indicate that ethylene is involved in Arabidopsis cauline leaf abscission induced by water stress and rewatering. Our results show that ethylene is involved in Arabidopsis cauline leaf abscission induced by water stress and rewatering, similar to leaf abscission in other plants.

Assembly and dynamics of the apple carposphere microbiome during fruit development and storage

Microbial communities associated with fruit can contribute to quality and pathogen resistance, but little is known about their assembly and dynamics during fruit development and storage. Three apple cultivars growing under the same environmental conditions were utilized to examine the apple carposphere microbiome composition and structure at different developmental stages and storage. There was a significant effect (Adonis, p ≤ 0.001) of fruit genotype and its developmental stages and storage times on the fruit surface microbial assemblage and a strong temporal microbial community succession was detected (Mantel test: R ≤ 0.5, p = 0.001) in both bacterial and fungal communities. A set of 15 bacterial and 35 fungal core successional taxa and members exhibiting differential abundances at different fruit stages were identified. For the first time, we show the existence of underlying universal dynamics in the assembly of fruit-associated microbiomes. We also provide evidence of strong microbial cross-domain associations and uncover potential microbe-microbe correlations in the apple carposphere. Together our findings shed light on how the fruit carposphere assemble and change over time, and provide new insights into fruit microbial ecology.

Role of the KNOTTED1-LIKE HOMEOBOX protein (KD1) in regulating abscission of tomato flower pedicels at early and late stages of the process

The KNOTTED1-LIKE HOMEOBOX PROTEIN1 (KD1) gene is highly expressed in flower and leaf abscission zones (AZs), and KD1 was reported to regulate tomato flower pedicel abscission via alteration of the auxin gradient and response in the flower AZ (FAZ). The present work was aimed to further examine how KD1 regulates signaling factors and regulatory genes involved in pedicel abscission, by using silenced KD1 lines and performing a large-scale transcriptome profiling of the FAZ before and after flower removal, using a customized AZ-specific microarray. The results highlighted a differential expression of regulatory genes in the FAZ of KD1-silenced plants compared to the wild-type. In the TAPG4::antisense KD1-silenced plants, KD1 gene expression decreased before flower removal, resulting in altered expression of regulatory genes, such as epigenetic modifiers, transcription factors, posttranslational regulators, and antioxidative defense factors occurring at zero time and before affecting auxin levels in the FAZ detected at 4 h after flower removal. The expression of additional regulatory genes was altered in the FAZ of KD1-silenced plants at 4-20 h after flower removal, thereby leading to an inhibited abscission phenotype, and downregulation of genes involved in abscission execution and defense processes. Our data suggest that KD1 is a master regulator of the abscission process, which promotes abscission of tomato flower pedicels. This suggestion is based on the inhibitory effect of KD1 silencing on flower pedicel abscission that operates via alteration of various regulatory pathways, which delay the competence acquisition of the FAZ cells to respond to ethylene signaling.

Global analysis of the apple fruit microbiome: are all apples the same?

We present the first worldwide study on the apple (Malus × domestica) fruit microbiome that examines questions regarding the composition and the assembly of microbial communities on and in apple fruit. Results revealed that the composition and structure of the fungal and bacterial communities associated with apple fruit vary and are highly dependent on geographical location. The study also confirmed that the spatial variation in the fungal and bacterial composition of different fruit tissues exists at a global level. Fungal diversity varied significantly in fruit harvested in different geographical locations and suggests a potential link between location and the type and rate of postharvest diseases that develop in each country. The global core microbiome of apple fruit was represented by several beneficial microbial taxa and accounted for a large fraction of the fruit microbial community. The study provides foundational information about the apple fruit microbiome that can be utilized for the development of novel approaches for the management of fruit quality and safety, as well as for reducing losses due to the establishment and proliferation of postharvest pathogens. It also lays the groundwork for studying the complex microbial interactions that occur on apple fruit surfaces.

Surgical and non-surgical approaches in the management of lower limb post-thrombotic syndrome

Introduction: Post-thrombotic syndrome (PTS) is a common lifelong condition affecting up to 50% of those suffering from deep vein thrombosis (DVT). PTS compromises function and quality of life with subsequent venous ulceration in up to 29% of those affected.Areas covered: A literature review of surgical and non-surgical approaches in the prevention and treatment of PTS was undertaken. Notable areas include the use of percutaneous endovenous interventions and the use of graduated compression stockings (GCS) after acute proximal DVT.Expert opinion: In patients with acute iliofemoral DVT, we think it is important to have a frank conversation with the patient about catheter-directed thrombolysis, aiming to reduce the severity of PTS experienced. We advocate ultrasound-accelerated thrombolysis with adjunctive procedures, such as deep venous stenting for proximal iliofemoral DVT. For patients with isolated femoral DVT, we believe that anticoagulation and GCS should be recommended. In patients with established PTS, we recommend GCS for symptomatic relief. We recommend that patients engage in regular exercise where possible with the prospect of gaining symptomatic relief. For those with severe PTS that has a significant effect on quality of life, we discuss the patient's case at a multi-disciplinary team meeting to plan for endovenous intervention.

Practical consensus recommendations for neo-adjuvant chemotherapy in triple negative breast cancer

This manuscript provides a practical and easy to use consensus recommendation to community oncologists on how to use neoadjuvant chemotherapy in triple negative breast cancer patients.

Practical consensus recommendations on management of HR + ve early breast cancer with specific reference to genomic profiling

Breast cancer is a heterogeneous disease and patients are managed clinically based on ER, PR, HER2 expression, and key risk factors. The use of gene expression assays for early stage disease is already common practice. These tests have found a place in risk stratifying the heterogeneous group of stage I–II breast cancers for recurrence, for predicting chemotherapy response, and for predicting breast cancer-related mortality. Most guidelines for hormone receptor (HR)–positive early breast cancer recommend addition of adjuvant chemotherapy for most women, leading to overtreatment, which causes considerable morbidity and cost. Expert oncologist discussed about strategies of gene expression assays and aid in chemotherapy recommendations for treatment of HR + ve EBC and the expert group used data from published literature, practical experience and opinion of a large group of academic oncologists to arrive at this practical consensus recommendations for the benefit of community oncologists.

Management of Acute Mesenteric Venous Thrombosis: A Systematic Review of Contemporary Studies

Background and Aims:

Acute mesenteric venous thrombosis accounts for up to 20% of all patients with acute mesenteric ischemia in high-income countries. Acute mesenteric venous thrombosis is nowadays relatively more often diagnosed with intravenous contrast-enhanced computed tomography in the portal phase than at explorative laparotomy No high-quality comparative studies between anticoagulation alone, endovascular therapy, or surgery exists. The aim of the present systematic review was to offer a contemporary overview on management.

Materials and Methods:

Eleven relevant published original studies with series of at least ten patients were retrieved from a Pub Med search between 2015 and 2020 using the Medical Subject Heading term “mesenteric venous thrombosis.”

Results:

When MVT is diagnosed early, immediate anticoagulation with either unfractionated heparin or subcutaneous low-molecular-weight heparin should commence. Surgeons need to be aware of the importance to scrutinize the computed tomography images themselves for assessment of secondary intestinal abnormalities to mesenteric venous thrombosis and the risk of bowel resection and worse prognosis. Progression toward peritonitis is an indication for explorative laparotomy and assessment of bowel viability. Frank transmural small bowel necrosis should be resected and bowel anastomosis may be delayed for several days until second look. Meanwhile, intravenous full-dose unfractionated heparin should be given at the end of the first operation. Postoperative major intra-abdominal or gastrointestinal bleeding occurs rarely, but the heparin effect can instantaneously be reversed by protamine sulfate. Patients who do not improve during conservative therapy with anticoagulation alone but without developing peritonitis may be subjected to endovascular therapy in expert centers. When the patient’s intestinal function has recovered, with or without bowel resection, switch from parenteral unfractionated heparin or low-molecular-weight heparin therapy to oral anticoagulation can be performed. There is a trend that direct oral anticoagulants are increasingly used instead of vitamin K antagonists. Up to now, direct oral anticoagulants have been shown to be equally effective with the same rate of bleeding complications. Patients with no strong permanent trigger factor for mesenteric venous thrombosis such as intra-abdominal cancer should undergo blood screening for inherited and acquired thrombophilia.

Conclusion:

Early diagnosis with emergency computed tomography with intravenous contrast-enhancement and imaging in the portal phase and anticoagulation therapy is necessary to be able to have a succesful non-operative succesful course.

Yeasts and Bacterial Consortia from Kefir Grains Are Effective Biocontrol Agents of Postharvest Diseases of Fruits

Fungal pathogens in fruits and vegetables cause significant losses during handling, transportation, and storage. Biological control with microbial antagonists replacing the use of chemical fungicides is a major approach in postharvest disease control, and several products based on single antagonists have been developed but have limitations related to reduced and inconsistent performance under commercial conditions. One possible approach to enhance the biocontrol efficacy is to broaden the spectrum of the antagonistic action by employing compatible microbial consortia. Here, we explore commercial kefir grains, a natural probiotic microbial consortium, by culture-dependent and metagenomic approaches and observed a rich diversity of co-existing yeasts and bacterial population. We report effective inhibition of the postharvest pathogen Penicillium expansum on apple by using the grains in its fresh commercial and milk-activated forms. We observed few candidate bacteria and yeasts from the kefir grains that grew together over successive enrichment cycles, and these mixed fermentation cultures showed enhanced biocontrol activities as compared to the fresh commercial or milk-activated grains. We also report several individual species of bacteria and yeasts with biocontrol activities against Penicillium rots on apple and grapefruit. These species with antagonistic properties could be further exploited to develop a synthetic consortium to achieve enhanced antagonistic effects against a wide range of postharvest pathogens.

Improved Prognosis and Low Failure Rate with Anticoagulation as First-Line Therapy in Mesenteric Venous Thrombosis

BACKGROUND

Monotherapy with anticoagulation has been considered as first-line therapy in patients with mesenteric venous thrombosis (MVT). The aim of this study was to evaluate outcome, prognostic factors, and failure rate of anticoagulation as monotherapy, and to identify when bowel resection was needed.

METHODS

Retrospective study of consecutive patients with MVT diagnosed between 2000 and 2015.

RESULTS

The overall incidence rate of MVT was 1.3/100,000 person-years. Among 120 patients, seven died due to autopsy-verified MVT without bowel resection and 15 underwent immediate bowel resection without prior anticoagulation therapy. The remaining 98 patients received anticoagulation monotherapy, whereof 83 (85%) were treated successfully. Fifteen patients failed on anticoagulation monotherapy, of whom seven underwent bowel resection and eight endovascular therapy. Endovascular therapy was followed by bowel resection in three patients. Two late bowel resections were performed due to intestinal stricture. The 30-day mortality rate was 19.0% in the former (2000-2007) and 3.2% in the latter (2008-2015) part of the study period (p = 0.006). Age ≥75 years (OR 12.4, 95% CI [2.5-60.3]), management during the former as opposed to the latter time period (OR 8.4, 95% CI [1.3-54.7]), and renal insufficiency at admission (OR 8.0, 95% CI [1.2-51.6]) were independently associated with increased mortality in multivariable analysis.

CONCLUSIONS

Short-term prognosis in patients with MVT has improved. Contemporary data show that monotherapy with anticoagulation is an effective first choice in MVT patients.

Practical consensus recommendation on when to do BRCA testing

BRCA-mutation associated breast cancer and to future cancer risks and sensitivity to systemic therapies. Now that rapid genetic testing for BRCA1 and BRCA2 mutations is available, BRCA mutation status can be considered when making treatment and prevention decisions for BRCA testing, BRCA mutation carriers with breast cancer. Expert group used data from published literature, practical experience, and opinion of a large group of academic oncologists, to arrive at practical consensus recommendations for use by the community oncologists.

The Tomato Hybrid Proline-rich Protein regulates the abscission zone competence to respond to ethylene signals

The Tomato Hybrid Proline-rich Protein (THyPRP) gene was specifically expressed in the tomato (Solanum lycopersicum) flower abscission zone (FAZ), and its stable antisense silencing under the control of an abscission zone (AZ)-specific promoter, Tomato Abscission Polygalacturonase4, significantly inhibited tomato pedicel abscission following flower removal. For understanding the THyPRP role in regulating pedicel abscission, a transcriptomic analysis of the FAZ of THyPRP-silenced plants was performed, using a newly developed AZ-specific tomato microarray chip. Decreased expression of THyPRP in the silenced plants was already observed before abscission induction, resulting in FAZ-specific altered gene expression of transcription factors, epigenetic modifiers, post-translational regulators, and transporters. Our data demonstrate that the effect of THyPRP silencing on pedicel abscission was not mediated by its effect on auxin balance, but by decreased ethylene biosynthesis and response. Additionally, THyPRP silencing revealed new players, which were demonstrated for the first time to be involved in regulating pedicel abscission processes. These include: gibberellin perception, Ca²⁺-Calmodulin signaling, Serpins and Small Ubiquitin-related Modifier proteins involved in post-translational modifications, Synthaxin and SNARE-like proteins, which participate in exocytosis, a process necessary for cell separation. These changes, occurring in the silenced plants early after flower removal, inhibited and/or delayed the acquisition of the competence of the FAZ cells to respond to ethylene signaling. Our results suggest that THyPRP acts as a master regulator of flower abscission in tomato, predominantly by playing a role in the regulation of the FAZ cell competence to respond to ethylene signals.

Testing for thrombophilia in mesenteric venous thrombosis - Retrospective original study and systematic review

The aim was to perform a local study of risk factors and thrombophilia in mesenteric venous thrombosis (MVT), and to review the literature concerning thrombophilia testing in MVT. Patients hospitalized for surgical or medical treatment of MVT at our center 2000-2015. A systematic review of observational studies was performed. In the local study, the most frequently identified risk factor was Factor V Leiden mutation. The systematic review included 14 original studies. The highest pooled percentage of any inherited thrombophilic factor were: Factor V Leiden mutation 9% (CI 2.9-16.1), prothrombin gene mutation 7% (CI 2.7-11.8). The highest pooled percentage of acquired thrombophilic factors were JAK2 V617F mutation 14% (CI -1.9-28.1). The wide range of frequency of inherited and acquired thrombophilic factors in different populations indicates the necessity to relate these factors to background population based data in order to estimate their overrepresentation in MVT. There is a need to develop guidelines for when and how thrombophilia testing should be performed in MVT.

De novo Transcriptome Sequencing and Development of Abscission Zone-Specific Microarray as a New Molecular Tool for Analysis of Tomato Organ Abscission

Abscission of flower pedicels and leaf petioles of tomato (Solanum lycopersicum) can be induced by flower removal or leaf deblading, respectively, which leads to auxin depletion, resulting in increased sensitivity of the abscission zone (AZ) to ethylene. However, the molecular mechanisms that drive the acquisition of abscission competence and its modulation by auxin gradients are not yet known. We used RNA-Sequencing (RNA-Seq) to obtain a comprehensive transcriptome of tomato flower AZ (FAZ) and leaf AZ (LAZ) during abscission. RNA-Seq was performed on a pool of total RNA extracted from tomato FAZ and LAZ, at different abscission stages, followed by de novo assembly. The assembled clusters contained transcripts that are already known in the Solanaceae (SOL) genomics and NCBI databases, and over 8823 identified novel tomato transcripts of varying sizes. An AZ-specific microarray, encompassing the novel transcripts identified in this study and all known transcripts from the SOL genomics and NCBI databases, was constructed to study the abscission process. Multiple probes for longer genes and key AZ-specific genes, including antisense probes for all transcripts, make this array a unique tool for studying abscission with a comprehensive set of transcripts, and for mining for naturally occurring antisense transcripts. We focused on comparing the global transcriptomes generated from the FAZ and the LAZ to establish the divergences and similarities in their transcriptional networks, and particularly to characterize the processes and transcriptional regulators enriched in gene clusters that are differentially regulated in these two AZs. This study is the first attempt to analyze the global gene expression in different AZs in tomato by combining the RNA-Seq technique with oligonucleotide microarrays. Our AZ-specific microarray chip provides a cost-effective approach for expression profiling and robust analysis of multiple samples in a rapid succession.

Modeling microalgal flocculation and sedimentation

In this study, a combined flocculation and sedimentation model is developed. The model predicts the time needed to reach a desired concentration of microalgal suspension in a sedimentation tank. The concentration of the particles as function of the time and the position in the tank is described. The model was validated with experimental data for Ettlia texensis. The concentration changes measured in time at different heights in the sedimentation vessel corresponded well with model predictions. The model predicts that it takes 25 h to reach a final concentration of 5.2 gDW L(-1), when the initial concentration is 0.26 gDW L(-1) and the tank height is 1m. This example illustrates the use of this model for the design of the settling tank needed for pre-concentration of microalgal biomass before further dewatering.

Effect of growth phase on harvesting characteristics, autoflocculation and lipid content of Ettlia texensis for microalgal biodiesel production

The effect of growth phase on the recovery of the autoflocculating microalgae Ettlia texensis was studied. In the stationary phase, 90% recovery was achieved after 3h settling. Scanning electron microscopic pictures revealed that extracellular polymeric substances (EPS) on the cell surface were involved in autoflocculation. During the stationary phase an increase of the protein fraction in the EPS was observed while the total fatty acids content increased. The autoflocculating properties of E. texensis combined with favourite fatty acid content and composition make this microalgae an excellent candidate for biodiesel production if harvested at the end of the stationary phase.

Ratio between autoflocculating and target microalgae affects the energy-efficient harvesting by bio-flocculation

The effect of ratio between autoflocculating and target microalgae in bio-flocculation was studied with emphasis on the recovery, sedimentation rate and energy demand for harvesting the target microalgae. When the autoflocculating microalgae Ettlia texensis, Ankistrodesmus falcatus and Scenedesmus obliquus were added to Chlorella vulgaris at a ratio of 0.25, the recovery of C. vulgaris increased from 25% to, respectively, 40%, 36% and 31%. The sedimentation rate increased as well. Addition of Tetraselmis suecica to Neochloris oleoabundans at a ratio of 0.25 increased the recovery from 40% to 50%. Application of bio-flocculation at a ratio of 0.25, followed by centrifugation reduces the energy demand for harvesting of the target microalgae from 13.8 MJ kgDW(-1) if only centrifugation is used to 1.83, 1.81, 1.53 and 1.34 MJ kgDW(-1), respectively, using T. suecica, E. texensis, A. falcatus and S. obliquus and 3h sedimentation before centrifugation.

Chronic adrenaline treatment fails to down-regulate the Del301-303-alpha2B-adrenoceptor in neuronal cells

BACKGROUND AND PURPOSE

A polymorphism of the human alpha(2B)-adrenoceptor (Del(301-303)-alpha(2B)-adrenoceptor) has been described, and this receptor exhibits reduced G-protein-coupled receptor kinase (GRK) phosphorylation and impaired short-term desensitization. Expression of the Del(301-303)-alpha(2B)-adrenoceptor also is associated with an increased risk for myocardial infarction in humans. Recent evidence from our laboratory suggests a quantitative relationship between cellular GRK3 expression levels and the sensitivity of the alpha(2B)-adrenoceptor to agonist-induced down-regulation. Therefore, the present study was undertaken to study agonist-induced down-regulation of the wild-type (WT)- and Del(301-303)-alpha(2B)-adrenoceptor in a neuronal cell model.

EXPERIMENTAL APPROACH

Haemagglutinin (HA) epitope-tagged WT- and Del(301-303)-alpha(2B)-adrenoceptor containing plasmids were constructed and the receptors were stably or transiently transfected in neuroblastoma/glioma hybrid NG108 cells. The expression levels in stable transfects were approximately 50 fmol x mg(-1). These cells were used to examine agonist-induced down-regulation and phosphorylation of the WT- and Del(301-303)-alpha(2B)-adrenoceptor.

KEY RESULTS

The Del(301-303)-alpha(2B)-adrenoceptor, compared with the WT-alpha(2B-)adrenoceptor, displayed reduced adrenaline-stimulated (20 microM) phosphorylation and did not down-regulate in response to adrenaline (20-1000 microM). Using immunofluorescence labelling, we observed that transiently transfected WT-alpha(2B)-adrenoceptors internalized upon adrenaline treatment whereas the Del(301-303)-alpha(2B)-adrenoceptor did not. Finally, we determined the effect of adrenaline on the Del(301-303)-alpha(2B)-adrenoceptor in cells stably over-expressing GRK3 3-fold. In spite of the GRK3 over-expression, 20-1000 microM ADR failed to down-regulate or to increase phosphorylation of the Del(301-303)-alpha(2B)-adrenoceptor in these cells.

CONCLUSIONS AND IMPLICATIONS

The results suggest that the 301-303 deletion mutation of the alpha(2B)-adrenoceptor eliminates agonist-induced down-regulation, an effect that cannot be overcome by increasing agonist concentration or by modest GRK3 over-expression.

Trabeculectomy and optic nerve head topography

The objective of the present study was to evaluate changes in optic nerve head parameters, measured by confocal laser tomography, before and after trabeculectomy in order to identify outcome measures for the management of glaucoma. The optic nerve head of 22 eyes (22 patients) was analyzed by confocal laser tomography with the Heidelberg retinal tomogram (HRT) before and after trabeculectomy. The median time between the first HRT and surgery was 4.6 months (mean: 7.7 +/- 8.3) and the median time between surgery and the second HRT was 10.8 months (mean: 12.0 +/- 6.8). The patients were divided into two groups, i.e., those with the highest (group A) and lowest (group B) intraocular pressure (IOP) change after surgery. Differences in the 12 standard topographic parameters before and after surgery for each group were evaluated by the Wilcoxon signed rank test and the differences in these parameters between the two groups were compared by the Mann-Whitney rank sum test. Multiple regression analysis was used to evaluate the influence of the change in IOP (DeltaIOP and DeltaIOP%) and the changes in the other parameters. There were significant differences in the HRT measures before and after surgery in group A only for cup volume. In group B, no parameter was statistically different. The changes in group A were not significantly different than those in group B for any parameter (P > 0.004, Bonferroni correction for multiple comparisons). DeltaIOP and DeltaIOP% had a statistically significant effect on Delta cup disk area, Delta cup volume and Delta mean cup depth. Changes in cup shape size were influenced significantly only by DeltaIOP. Some optic disc parameters measured by HRT presented a significant improvement after filtering surgery, depending on the amount of IOP reduction. Long-term studies are needed to determine the usefulness of these findings as outcome measures in the management of glaucoma.

Influence of surgical reduction of intraocular pressure on regions of the visual field with different levels of sensitivity

PURPOSE

To determine whether the ability to document improvement in visual fields after intraocular pressure (IOP) reduction can be enhanced by focusing on regions of the field with different levels of sensitivity.

DESIGN

Cohort study.

METHODS

This is a retrospective study.

SETTING

Yale Eye Center.

STUDY POPULATION

The visual fields (Octopus G2) of 30 eyes of 30 patients undergoing trabeculectomy.

OBSERVATION PROCEDURE

Visual fields were evaluated a mean of three months before and 7.8 months after surgery.

MAIN OUTCOME MEASURES

Change in sensitivity between the preoperative and postoperative visual fields (Delta S) was evaluated globally by comparing all 59 points of sensitivity and regionally in three groups according to preoperative sensitivity (pre-S): 25% of highest, 50% intermediate, and 25% of lowest points of sensitivity. Improvement in Delta S was also correlated with preoperative mean defect (pre-MD), percent intraocular pressure (IOP) reduction (Delta IOP%), and patient's age.

RESULTS

Six visual fields showed improvement in Delta S when evaluated globally and nine showed improvement in pre-S subgroups. Of the latter, all nine showed improvement in the subgroup with the lowest pre-S, and two in the intermediate subgroup, but none in the subgroup with the highest pre-S. Combining the subgroups with the lowest pre-S and the highest Delta IOP% was associated with the highest mean Delta S.

CONCLUSION

The ability to document improvement in visual fields following surgical reduction of IOP may be enhanced by focusing on subgroups of test points with lower baseline sensitivity.

Visually significant cystoid macular edema in pseudophakic and aphakic patients with glaucoma receiving latanoprost

PURPOSE

To investigate the incidence of visually significant cystoid macular edema associated with the use of latanoprost in patients with glaucoma after cataract surgery.

PATIENTS AND METHODS

This is a multicenter, retrospective study of 185 patients, of whom 173 were pseudophakic (212 eyes) and 12 were aphakic (13 eyes), who were treated for glaucoma with latanoprost 0.005%. The posterior lens capsule was intact in 125 eyes, open or absent as a result of surgery in 25 eyes, and status-post-yttrium-aluminum-garnet capsulotomy in 75 eyes. Visual acuity was documented before and after initiating latanoprost therapy, and patients with a reduction of two or more lines on the Snellen chart were examined by fluorescein angiography for cystoid macular edema.

RESULTS

Visual reduction was documented in four (2.16%) patients. Three of the four patients had cystoid macular edema, and the fourth was thought to have lost a central island of vision from glaucoma. The three patients with cystoid macular edema all had ruptured posterior capsules, requiring anterior vitrectomy, and one had a previous episode of cystoid macular edema 3 years before starting latanoprost therapy.

CONCLUSION

These findings suggest that visually significant cystoid macular edema associated with latanoprost therapy in pseudophakic or aphakic patients is uncommon. If there is a cause-and-effect relationship between latanoprost therapy and clinically significant cystoid macular edema, the incidence appears to be low.

Hepatitis B vaccination among health care workers and students of a medical college

OBJECTIVE

To study the vaccination status against Hepatitis B among health care workers and students of a medical school.

MATERIALS AND METHODS

It is a descriptive study done at Allama Iqbal Medical College, Lahore. The participants comprised of 206 health care workers of various categories and 327 medical students. The main outcome measure was vaccination status and reasons for non-vaccination.

RESULTS

Only 49% health care workers and 42.20% medical students were vaccinated. The main reasons for non-vaccination (47.7%) among health care workers was the high cost of vaccination, while the most often cited reason (33.7%) among medical student was the belief that they were not at risk. This belief was also prevalent among nurses (36.4%), laboratory workers (38.6%) and paramedics (33.2%).

CONCLUSION

In a low-income country like Pakistan the health institutions should bear the cost for vaccinating their staff. Efforts should also be made to impart appropriate health education regarding hepatitis B infection.

Lack of quinone reductase activity suggests that amyloid-beta peptide/ERAB induced lipid peroxidation is not directly related to production of reactive oxygen species by redoxcycling

Mitochondrial type II hydroxyacyl-CoA dehydrogenase (ERAB) has recently been shown to mediate amyloid-beta peptide (Abeta) induced apoptosis and neurodegeneration. The precise mechanism of cell death induction is unknown, however, Abeta inhibits ERAB activities and as a result of ERAB-Abeta interactions, enhanced formation of lipid peroxidation products occur. The possibility that ERAB mediates quinone reduction is therefore investigated, thus giving the potential of redoxcycling and production of reactive oxygen species, leading to lipid peroxidation. Recombinant human ERAB was produced in a bacterial expression system and enzymological properties were evaluated. Using several orthoquinones as substrates, no ERAB mediated quinone reductase activity was found either in the presence or absence of Abeta, suggesting that the observed in vivo lipid peroxidation is a result of other mechanisms than redoxcycling by quinones.

Binding of amyloid beta-peptide to mitochondrial hydroxyacyl-CoA dehydrogenase (ERAB): regulation of an SDR enzyme activity with implications for apoptosis in Alzheimer's disease

The intracellular amyloid beta-peptide (A beta) binding protein, ERAB, a member of the short-chain dehydrogenase/reductase (SDR) family, is known to mediate apoptosis in different cell lines and to be a class II hydroxyacyl-CoA dehydrogenase. The A beta peptide inhibits the enzymatic reaction in a mixed type fashion with a Ki of 1.2 micromol/l and a KiES of 0.3 micromol/l, using 3-hydroxybutyryl-CoA. The peptide region necessary for inhibition comprises residues 12-24 of A beta1-40, covering the 16-20 fragment, which is the minimum sequence for the blockade of A beta polymerization, but that minimal fragment is not sufficient for more than marginal inhibition. The localization of ERAB to the endoplasmic reticulum and mitochondria suggests a complex interaction with components of the programmed cell death machinery. The interaction of A beta with ERAB further links oxidoreductase activity with both apoptosis and amyloid toxicity.

Effect of reversible and irreversible ischemia on marker enzymes of BBM from renal cortical PT subpopulations

The effect of the reversible and relatively irreversible ischemia induced acute renal failure (ARF) in the activities of alkaline phosphatase (AlkPase) and gamma-glutamyltransferase (GGTase) after early (15-30 min) and prolonged (45-60 min) ischemia in the homogenates, and the brush-border membranes (BBM) from rat renal whole, superficial (SC), and juxtamedullary (JMC) cortices were studied. The enzyme activities declined progressively in proportion to the duration of ischemia. Early blood reflow of 15 min to the ischemic rats caused a further decrease in the enzyme activities. However, prolonged reflow (up to 120 min) resulted in partial reversal of the ischemic effect in the early but not in the prolonged ischemic rats. The decrease in the enzyme activities was due to the loss of membrane-bound enzyme components from the damaged BBM into the supernatant fraction as membrane-free enzymes. The activities of AlkPase and GGTase were significantly more decreased by the ischemia in the brush-border membrane vesicles (BBMV)-JMC than in BBMV-SC. The rate of recovery due to reflow for AlkPase was greater in BBMV-SC than apparently for GGTase in BBMV-JMC in early ischemic (15-30 min) rats.

Videothoracoscopic ligation of patent ductus arteriosus--a case report

Video-assisted thoracoscopic surgical interruption (VTSI) of patent ductus arteriosus (PDA) is a relatively new technique when compared to surgical closure and transcatheter endovascular closure. Besides its minimally invasive nature, VTSI is the best option for neonates. Surgical approach may lead to late scoliosis in neonates and the vessels of neonates are too small for the transcatheter approach. VTSI potentially may prove to have lower morbidity and mortality than classic surgical closure of PDA. This article reviews the successful videothoracoscopic ligation of PDA in a 13-year-old girl.