Neighborhood Deprivation and Changes in Oral Health in Older Age: A Longitudinal Population-Based Study.

The aim of this study was to examine the extent to which neighborhood-level socioeconomic factors (objective and perceived) are associated with poor oral health in older adults over time, independent of individual socioeconomic position. Data for this cross-sectional and longitudinal observation study came from a socially and geographically representative cohort of men aged 71 to 92 y in 2010-12 (n = 1,622), drawn from British general practices, which was followed up in 2018-19 (aged 78-98 y; N = 667). Dental measures at both times included number of teeth, periodontal pocket depth, self-rated oral health, and dry mouth. Neighborhood deprivation was based on Index of Multiple Deprivation (IMD) and a cumulative index measuring perceptions about local environment. Individual-level socioeconomic position was based on longest-held occupation. Multilevel and multivariate logistic regressions, adjusted for relevant sociodemographic, behavioral, and health-related factors, were performed to examine the relationships of dental measures with IMD and perceived neighborhood quality index, respectively. Cross-sectionally, risks of tooth loss, periodontal pockets, and dry mouth increased from IMD quintiles 1 to 5 (least to most deprived); odds ratios (ORs) for quintile 5 were 2.22 (95% confidence interval [CI], 1.41-3.51), 2.82 (95% CI, 1.72-4.64), and 1.51 (95% CI, 1.08-2.09), respectively, after adjusting for sociodemographic, behavioral, and health-related factors. Risks of increased pocket depth and dry mouth were significantly greater in quintile 5 (highest problems) of perceived neighborhood quality index compared to quintile 1. Over the 8-y follow-up, deterioration of dentition (tooth loss) was significantly higher in the most deprived IMD quintiles after full adjustment (OR for quintile 5 = 2.32; 95% CI, 1.09-4.89). Deterioration of dentition and dry mouth were significantly greater in quintile 5 of perceived neighborhood quality index. Neighborhood-level factors were associated with poor oral health in older age, both cross-sectionally and longitudinally, particularly with tooth loss, and dry mouth, independent of individual-level socioeconomic position.

The role of primary school composition in affective decision-making: a prospective cohort study.

PURPOSE: School-level characteristics are known to be associated with pupils' academic and cognitive ability but also their socioemotional development. This study examines, for the first time, whether primary school characteristics are associated with pupils' affective decision-making too. METHODS: The sample included 3,141 children participating in the Millennium Cohort Study with available data on their school's characteristics, according to the National Pupil Database, at age 7 years. Decision-making was measured using the Cambridge Gambling Task at age 11 years. We modelled data using a series of sex-stratified linear regression analyses of decision-making (risk-taking, quality of decision-making, risk adjustment, deliberation time, and delay aversion) against four indicators of school composition (academic performance and proportions among pupils who are native speakers of English, are eligible for free school meals and have special educational needs). RESULTS: After adjustment for individual and family-level confounding, schools with a higher average academic performance showed more delay aversion among males, and among females, higher deliberation time and lower risk-taking. Schools with proportionally more native English speakers had higher deliberation time among males. Schools with proportionally more pupils eligible for free school meals showed lower scores on quality of decision-making among males. Schools with proportionally more children with special educational needs showed better quality of decision-making among males and lower risk-taking among females. CONCLUSION: The findings of this study can be used to target support for primary schools. Interventions aiming to support lower-achieving schools and those with less affluent intakes could help to improve boys' affective decision-making.

Mapping the Secretome of Dental Pulp Stem Cells Under Variable Microenvironmental Conditions.

There is substantial evidence supporting the anti-inflammatory and regenerative potential of dental pulp stem cells (DPSCs) through direct cell transplantation or paracrine action. However, DPSC secretome profile remains inadequately studied. This study provides proteomic profiling of the human DPSC secretome by comparatively analysising cell lysates and respective culture supernatants (i.e. conditioned media-CM) under variable oxygen tension conditions (normoxia-20% O2/CM_Norm vs. hypoxia 2% O2/CM_Hyp) and/or stimulation with Tumor Necrosis Factor alpha (TNF-α). DPSC-CM samples and respective crude lysates (DPSC-CL) were collected and subjected to SDS-PAGE, followed by LC-MS/MS analysis. The identified proteins were analyzed by Gene Ontology, Reactome, and String databases. The anti-inflammatory properties of DPSC-CMs were validated via an in vitro RAW_246.7 murine macrophages model through evaluation of the expression of pro-and anti-inflammatory markers by real-time PCR. Results showed a total of 2413 proteins identified in CM_Norm, 2479 in CM_Norm+TNF-α, 1642 in CM_Hyp, and 2002 in CM_Hyp + TNF-α samples. CM_Norm contained 122 proteins statistically significantly upregulated compared to the CM_Hyp and involved in pathways related to "ECM organization", "cellular response to hypoxia", and "IL signaling". Functional network analysis showed that TGFß1, TIMP1 and TIMP2 were key nodes among proteins significantly upregulated in the CM_Norm compared to the CM_Hyp, interacting with more than 10 proteins, each. DPSC-CM application in the in vitro RAW_246.7 model decreased the expression of pro-inflammatory markers (MMP-3, MMP-9, MMP-13, MCP-1), while increasing anti-inflammatory markers (IL-10). Overall, DPSC-CM collected under normoxic conditions is enriched with anti-inflammatory, tissue repair and regenerative factors, which prompts further investigation on its therapeutic applications.

Epidural abscess imitating recurrent pilonidal sinus: a case report.

Pilonidal sinus or pilonidal cyst is a common benign disease, affecting mostly young working men. We present the first case of an epidural abscess imitating pilonidal sinus. A 33-year old male, suffering from previously undiagnosed and untreated diabetes mellitus (DM), presented to our emergency department (ER), one month after open surgical treatment of pilonidal sinus, due to weakness and fever. After re-operation of the pilonidal cyst and due to post-operative pus production and continuation of fever a computer tomogr aphy (CT )scan was performed revealing an epidural abscess extending from the thoracic vertebrae 12 (T-12) to the sacrococcygeal area. At that point he underwent new surgery for drainage of the epidural abscess. The patient received intravenous antimicrobial treatment and was discharged on the 23rd postoperative day without signs or symptoms of infection. At follow up for a whole year no signs of recurrence have been observed.

Spontaneous splenic artery aneurysm rupture in a 38-year old female: a case report.

Splenic artery aneurysm (SAA) is a rare and extremely difficult diagnosis. A rare case of a ruptured SAA in a 38-year old female, firstly treated with endovascular embolization and then with splenectomy, is presented. A 38-year old female presented to the emergency department with epigastric pain and fainting episodes. Direct catheter angiography revealed a ruptured SAA and distal, as well as proximal coil embolization was performed. Due to abdominal compartment syndrome the patient underwent open surgery with splenic artery ligation and splenectomy. Postoperative she showed signs of sepsis and was treated with i.v. fluids, steroids, packed red blood cells, platelets, fresh frozen plasma and antimicrobial treatment. Additionally, a multidrug resistant Acinetobacter baumanni was yielded from the urine culture. She had a satisfactory recovery. She is followed up a total of 5 years with no signs of overwhelming post-splenectomy infection syndrome. Direct catheter angiography is a very helpful option in diagnosis, as well as treatment, but a close monitoring after embolization is essential. Furthermore, post-splenectomy sepsis is a severe disease with high mortality rates that requires immediate appropriate treatment.

Measuring stigma in children receiving mental health treatment: Validation of the Paediatric Self-Stigmatization Scale (PaedS).

BACKGROUND: Research on the impact of stigma associated with mental illness in children is scarce. Considering the known negative effects of stigma associated with mental illness in adults, it is crucial to explore the stigma experienced by children who access mental health treatment. However, no scale measuring self-stigmatization in younger children is available to date. This study aimed to develop and validate such a scale, the Paediatric Self-Stigmatization Scale (PaedS). METHODS: A total of 156 children (119 receiving outpatient and 37 receiving inpatient treatment), aged 8-12 years, completed the PaedS, the Self-Perception Profile for Children and the Pediatric Quality of Life Inventory (PedsQL - Child Report, ages 8-12). In addition, parents completed the PedsQL (Parent Report for Children, ages 8-12), the Strengths and Difficulties Questionnaire (SDQ) and a modified subscale of the PaedS measuring the children's rejection by others due to their mental health difficulties. RESULTS: A confirmatory factor analysis showed that a four-factor structure, comprising Societal Devaluation, Personal Rejection, Self-Stigma and Secrecy scales, had excellent fit to the data (CFI=0.95; TLI=0.95; RMSEA=0.05). Child-reported PaedS scores were positively correlated with parental-reported PaedS scores and negatively with PedsQL, the SDQ, and 5 out of 6 subscales of the Self-Perception Profile for Children, suggesting adequate convergent validity (all P-values<0.05). CONCLUSIONS: The PaedS is a valid instrument, which is hoped to advance the understanding of self-stigmatization in children with mental health difficulties and contribute to its prevention.

Analytical characteristics and comparative evaluation of Aptima HCV quant Dx assay with the Abbott RealTime HCV assay and Roche COBAS AmpliPrep/COBAS TaqMan HCV quantitative test v2.0.

BACKGROUND: The Aptima HCV Quant Dx assay (Aptima assay) is a fully automated quantitative assay on the Panther® system. This assay is intended for confirmation of diagnosis and monitoring of HCV RNA in plasma and serum specimens. The purpose of the testing described in this paper was to evaluate the performance of the Aptima assay. METHODS: The analytical sensitivity, analytical specificity, precision, and linearity of the Aptima assay were assessed. The performance of the Aptima assay was compared to two commercially available HCV assays; the Abbott RealTime HCV assay (Abbott assay, Abbott Labs Illinois, USA) and the Roche COBAS Ampliprep/COBAS Taqman HCV Quantitative Test v2.0 (Roche Assay, Roche Molecular Systems, Pleasanton CA, USA). The 95% Lower Limit of Detection (LoD) of the assay was determined from dilutions of the 2nd HCV WHO International Standard (NIBSC 96/798 genotype 1) and HCV positive clinical specimens in HCV negative human plasma and serum. Probit analysis was performed to generate the 95% predicted detection limits. The Lower Limit of Quantitation (LLoQ) was established for each genotype by diluting clinical specimens and the 2nd HCV WHO International Standard (NIBSC 96/798 genotype 1) in HCV negative human plasma and serum. Specificity was determined using 200 fresh and 536 frozen HCV RNA negative clinical specimens including 370 plasma specimens and 366 serum specimens. Linearity for genotypes 1 to 6 was established by diluting armored RNA or HCV positive clinical specimens in HCV negative serum or plasma from 8.08 log IU/mL to below 1 log IU/mL. Precision was tested using a 10 member panel made by diluting HCV positive clinical specimens or spiking armored RNA into HCV negative plasma and serum. A method comparison was conducted against the Abbott assay using 1058 clinical specimens and against the Roche assay using 608 clinical specimens from HCV infected patients. In addition, agreement between the Roche assay and the Aptima assay using specimens with low HCV concentrations (

The Significance of Inflow Artery and Tourniquet Derived Cephalic Vein Diameters on Predicting Successful Use and Patency of Arteriovenous Fistulas for Haemodialysis.

OBJECTIVE: To investigate the significance of inflow artery and cephalic vein diameters on predicting patency of radiocephalic and brachiocephalic arteriovenous fistulas (AVFs). DESIGN: Single centre study with retrospective analysis of prospectively collected data between November 2010 and July 2015. METHODS: A detailed history and physical examination was undertaken, including age, gender, history and duration of haemodialysis, cause of chronic kidney disease, and the presence of comorbidities/risk factors. Pre-operative arterial and venous upper extremity mapping was performed and inner vessel diameter was recorded, using a tourniquet for the veins. Outcome measures included AVF use (functionality), primary, primary assisted, secondary, and functional secondary patency. RESULTS: One hundred and thirty five AVFs (57 and 78 radiocephalic and brachiocephalic AVFs, respectively) were constructed and followed up for 5 years. A cephalic vein diameter <4.3 mm (lower three quartiles) was the single independent predictor of inferior secondary and also functional secondary patency of radiocephalic AVFs (p = .02, HR 11.2, 95% CI 1.44-90.9). A brachial artery diameter ≤4.1 mm (lowest quartile) was an independent predictor of AVF functionality (57% vs. 83% for larger arteries, p = .017), and inferior primary, primary assisted, secondary, and functional secondary patency of brachiocephalic AVFs (primary assisted patency 21.9% vs. 55.9% at 3 years, p = .001/log-rank test, HR 3.1, p = .002/Cox regression). The presence of lower extremity PAD or use of dual antithrombotics was also independently associated with an inferior secondary patency. The number of risk factors (brachial artery diameter ≤4.1 mm, PAD, and use of dual antithrombotics) demonstrated risk stratification capabilities for functional secondary patency. CONCLUSIONS: Among patients undergoing radiocephalic AVFs, a tourniquet derived cephalic vein diameter <4.3 mm was the single independent predictor of inferior secondary and functional secondary patency. Among patients undergoing brachiocephalic AVFs, all patency rates were inferior in the presence of a brachial artery diameter ≤4.1 mm and secondary patency was inferior in the presence of multiple risk factors.

Detection of candidate biomarkers of prostate cancer progression in serum: a depletion-free 3D LC/MS quantitative proteomics pilot study.

BACKGROUND: Prostate cancer (PCa) is the most common male cancer in the United Kingdom and we aimed to identify clinically relevant biomarkers corresponding to stage progression of the disease. METHODS: We used enhanced proteomic profiling of PCa progression using iTRAQ 3D LC mass spectrometry on high-quality serum samples to identify biomarkers of PCa. RESULTS: We identified >1000 proteins. Following specific inclusion/exclusion criteria we targeted seven proteins of which two were validated by ELISA and six potentially interacted forming an 'interactome' with only a single protein linking each marker. This network also includes accepted cancer markers, such as TNF, STAT3, NF-κB and IL6. CONCLUSIONS: Our linked and interrelated biomarker network highlights the potential utility of six of our seven markers as a panel for diagnosing PCa and, critically, in determining the stage of the disease. Our validation analysis of the MS-identified proteins found that SAA alongside KLK3 may improve categorisation of PCa than by KLK3 alone, and that TSR1, although not significant in this model, might also be a clinically relevant biomarker.

Outcome of transplantation in renal allograft recipients from cadaveric donors with standard and expanded criteria: a single-center experience.

INTRODUCTION: The increasing number of patients requiring kidney transplantation and the lack of available organs has led to the utilization of kidneys from expanded criteria donors (ECD). AIM: The comparison of the clinical outcome of renal transplantation, performed in a single center, between allograft recipients from standard (SCD) and expanded criteria donors (ECD). PATIENTS AND METHODS: Data from 215 cadaveric renal transplantations performed during a 16 year period at the University Hospital of Patras were retrospectively studied. Donors' and recipients' characteristics (gender, age, history of hypertension and diabetes mellitus, cold ischemia time, post-transplant and long term graft function) were analyzed. RESULTS: Grafts from donors with expanded criteria (ECD, n = 53) were allocated to older recipients whereas grafts from donors with standard criteria (SCD, n = 162) were allocated to younger recipients. The mean cold ischemia time was 1,146 min and was similar between the two groups of patients. Patients' survival rates were similar between allograft recipients from SCD and ECD up to the 5(th) post-transplant year of follow-up. Graft survival was significantly better in allograft recipients from SCD during a 5-year follow-up period. A significantly lower eGFR was noted in allograft recipients from ECD in comparison to those from SCD throughout the observation period. Cold ischemia time was positively correlated to the development of DGF, while patients with DGF had significantly worse graft function throughout the observation period. CONCLUSION: Patient survival from ECD is comparable to that from SCD but graft survival is significantly lower. However, since renal function of recipients from ECD is adequate for long term period, grafts from ECD should be used in older patients.

Parameters influencing blood erythropoietin levels of renal transplant recipients during the early post-transplantation period.

AIM: Renal transplantation is accompanied by restoration of renal function and endogenous erythropoietin production. The purpose of this study was to investigate the time-related changes of endogenous erythropoietin secretion in the early renal post-transplant period and the influence of various parameters to this process. METHODS: Fifty-eight patients were enrolled in the study and followed up for 3 months after successful renal transplantation. Erythropoietin levels were measured at regular intervals and correlated with renal function, cold ischemia time and immunosuppressive regimen used. RESULTS: Two peaks of serum erythropoietin levels were observed: an early peak that occurred within two days after transplantation and a late one, between weeks 2 and 4, which resulted in increased blood hemoglobin levels. Factors that were found to correlate with erythropoietin levels were delayed graft function, cyclosporine use and prolonged cold ischemia time. Serum creatinine did not correlate to erythropoietin levels although the reduction of serum creatinine preceded the rise of erythropoietin levels. Normal hemoglobin values were restored about three months after successful renal transplantation. CONCLUSION: Serum erythropoietin levels increase during the early post-transplantation period resulting in correction of anemia three months after a successful renal transplantation. Restoration of allograft function is a prerequisite for erythropoietin secretion, while cold ischemia time and immunosuppressive regimen affect graft function.

Gastrointestinal disorders after renal transplantation.

BACKGROUND: Gastrointestinal disorders (GDs) are common in renal transplant recipients. The main cause of GDs seems to be the use of immunosuppressive medications, especially mycophenolic acid in the form of mycophenolate mofetil (MMF). OBJECTIVE: The aim of this study was to estimate the frequency and severity of GDs in renal allograft recipients with the use of the Gastrointestinal Symptom Rating Scale (GSRS). METHODS: Eighty-five renal allograft recipients, 50 ± 12 years old, treated with methylprednisolone, calcineurin inhibitor (cyclosporine [CsA], n = 42; tacrolimus (TAC), n = 43), and MMF were studied. RESULTS: At the time of completion of the GSRS questionnaire, 38 of the 85 patients (45%) already had their MMF dose reduced because of GDs. Only 15 patients (18%) were totally free from GDs. The most frequent and severe GDs recorded were indigestion and diarrhea who were significantly more frequent in women (P = .045). GDs were recorded in patients receiving both standard and reduced dose of MMF. MMF dose was significantly associated only with diarrhea. Although TAC-treated patients had the highest mean GSRS scores, no statistically significant differences were observed compared with CsA-treated patients. In 31 patients, MMF was replaced by enteric-coated mycophenolate sodium (EC-MPS) and new questionnaires were completed 1 month later. Significant improvement in total and all subscores of GSRS was demonstrated (P < .001). Although EC-MPS dose tolerated by the patients was higher than MMF dose, the difference was not statistically significant. CONCLUSIONS: Female sex and the use of MMF, especially in combination with TAC, are related to the occurrence of severe gastrointestinal symptoms. Substitution of MMF with EC-MPS significantly reduces the severity of symptoms and permits the use of higher doses.

Ezetimibe is effective in the treatment of persistent hyperlipidemia of renal allograft recipients.

INTRODUCTION: Ezetimibe is a hypolipidemic agent acting via inhibition of cholesterol absorption from the small intestine. The effectiveness and safety of long-term administration of ezetimibe was evaluated in renal allograft recipients with persistent hyperlipidemia. PATIENTS AND METHODS: 67 renal allograft recipients with post-transplantation hyperlipidemia resistant to statins were included in the study; 11 were treated with ezetimibe (10 mg/day) alone and 56 with ezetimibe and statin. The effectiveness of ezetimibe was assessed by determination of total cholesterol (TC), LDL cholesterol (LDL-C), HDL cholesterol (HDL-C) and triglycerides (TR). Its safety was determined by liver enzymes (ALT, AST), LDH, CPK, serum creatinine and blood levels of immunosuppressive drugs (cyclosporine, tacrolimus, everolimus, sirolimus) over the follow-up period of 18±6 months. RESULTS: A significant reduction of TC and LDL-C blood levels by 25% and 34% respectively, was observed during the first month of treatment with ezetimibe (p<0.001). This reduction was maintained for the whole period of ezetimibe administration. Renal function remained stable over the follow-up period, while no changes of the blood levels of immunosuppressive drugs were observed. Liver enzymes, LDH and CPK remained normal in all patients except for one diabetic patient who developed rhabdomyolysis. Apart from gastrointestinal symptoms in 2 patients, no other side effects were observed. CONCLUSION: Combination of ezetimibe with statins represents an effective and safe regimen for treatment of persistent hyperlipidemia in renal allograft recipients.

Perspectives for integrated municipal solid waste management in Thessaloniki, Greece.

Local authorities need updated and reliable data on the quantity and the quality of the waste generated in their area, in order to establish an integrated solid waste management system capable of fulfilling regional and national waste management targets. This paper presents information about the quantity and the characteristics of the municipal solid waste generated in Thessaloniki, which is the second largest city in Greece. It is based on the results of three research programs investigating the evolution of municipal solid waste. The investigations were carried out over the last 20 years at the landfill of Thessaloniki by the same research group using statistically acceptable practices for sampling and hand sorting. The results show a great increase in the incoming quantities during the last years and a significant increase of the per capita generation. There is also a significant change in the composition, demonstrated mainly by a decrease in the organic fraction followed by an increase of packaging materials (paper and plastic).

Microchimerism in peripheral blood and urine in renal transplant recipients: preliminary results.

The role of microchimerism in peripheral blood and urine of renal transplant recipients remains a matter of debate, depending on the sensitivity of the methods used for detection. We studied 17 female renal transplant recipients who had received renal allografts from male donors. Polymerase chain reaction (PCR) was applied to blood and urine for the microsatellite markers D1S80, DYZ1, TH01, and kalphai SE33. Detection of DYZ1 that is present only on the Y chromosome was considered proof for microchimerism. No microchimerism was detected in peripheral blood, whereas it could be detected in the urine of 8/17 (48%) patients. There were no differences between patients with and without microchimerism regarding patient age, dialysis vintage, immunosuppression, time post-transplantation, and allograft function as measured using serum creatinine, creatinine clearance, and proteinuria. Two patients in each group showed chronic allograft dysfunction. These findings raise questions regarding the role of microchimerism in renal transplantation.

Regional celiac artery infusion in the adjuvant treatment of pancreatic cancer.

UNLABELLED: We performed adjuvant celiac artery infusion in pancreatic cancer, to find out whether this treatment prolongs survival and changes the biology of the disease after resection, especially by reducing liver metastasis. PATIENTS AND METHODS: Thirty-one patients received cyclic celiac artery infusions (CAI) after resection of their pancreatic cancer (27 ductal, 4 cystadenocarcinoma). The treatment consisted of 6 cycles (1 cycle = 5 days treatment) intra-arterial infusion using Seldingers technique with mitoxantrone A (Novantron) 10 mg/m2 d1, 5-fluorouracil + folinic acid 600 mg/m2 + 170 mg/m2 d2-d4 and cis-platinum 60 mg/m2 d5. Four to 5-week intervals between each cycle of chemotherapy were scheduled. The patients were monitored for toxicity, development of disease progression and survival. RESULTS: The median survival time was 21 months. During an observation period of 19 months, 70% of the patients developed disease progression. In 50% of cases the progression was local, in 40% intraperitoneal while in 15% liver metastases developed. The median survival time of the CAI (celiac artery infusion)-treated patient group compared favorably to the median survival of 9.3 months in a matched historical control group, being significantly longer (p < 0.0003). CONCLUSION: Adjuvant celiac artery infusion seemed to prolong median survival and the occurrence of liver metastases appeared to be delayed or reduced.

Surgical outcome and hospital cost analyses of laparoscopic and open tension-free hernia repair.

Surgeons who favor the laparoscopic repair of groin hernias must limit the additional costs associated with this technique, which is not universally acknowledged to be superior to other less expensive open tension-free repairs. This retrospective study compared outcome and costs between laparoscopic and open tension-free hernia repair in 320 patients with inguinal hernias. Patients underwent either (a) transabdominal preperitoneal procedure (TAPP; 60 patients, 72 procedures), (b) totally extraperitoneal procedure (TEP; 174 patients, 202 procedures), or (c) open tension-free procedure (86 patients, 105 procedures). Regarding important postoperative complications there were two (3.3%) recurrences in the TAPP group and one (0.6%) in the TEP group, and six (9.9%) transient neuralgias in the TAPP group and one (1.2%) in the tension-free group. There were no deaths, no testicular atrophies, and no wound or mesh infections. The mean hospital postoperative stay was the same in the three groups (1 day). Mean operating time was shorter in the tension-free group concerning the unilateral cases and shorter in the TEP group concerning the bilateral cases. Fewer patients required analgesia during the first 6 h after the operative procedure in the TEP group than in the other two groups. The mean total costs were 483.90 euros in the open tension-free repair, 763.20 euros in the TAPP repair, and 572.50 euros in the TEP repair. The open procedure was the cheaper for the hospital. Laparoscopic hernia repair and tension-free repair as described by Gilbert are comparable in postoperative complications. TEP hernia repair is associated with less postoperative pain and earlier return to normal activities, but it is more expensive and continues to be a difficult procedure. Open tension-free repair is the least expensive method and is easier to learn than the other two procedures.