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1.
Acta Biomater ; 127: 41-55, 2021 06.
Article in English | MEDLINE | ID: mdl-33812072

ABSTRACT

This review recognizes a unique calcium phosphate (CaP) phase known as monetite or dicalcium phosphate anhydrous (DCPA, CaHPO4), and presents an overview of its properties, processing, and applications in orthopedics. The motivation for the present effort is to highlight the state-of-the-art research and development of monetite and propel the research community to explore more of its potentials in orthopedics. After a brief introduction of monetite, we provide a summary of its various synthesis routes like dehydration, solvent-based, energy-assisted processes and also discuss the formation of different crystal structures with respect to the synthesis conditions. Subsequently, we discuss the material's noteworthy physico-chemical properties including the crystal structure, vibrational spectra, solubility, thermal decomposition, and conversion to other phases. Of note, we focus on the biological (in vitro and in vivo) properties of monetite, given its ever-increasing popularity as a biomaterial for medical implants. Appropriately, we discuss various orthopedic applications of monetite as bone cement, implant coatings, granules for defect fillers, and scaffolds. Many in vitro and in vivo studies confirmed the favorable osteointegration and osteoconduction properties of monetite products, along with a better balance between implant resorption and new bone formation as compared to other CaP phases. The review ends with translational aspects of monetite and presents thoughts about its possible future research directions. Further research may explore but not limited to improvements in mechanical strength of monetite-based scaffolds, using monetite particles as a therapeutic agent delivery, and tissue engineering strategies where monetite serves as the biomaterial. STATEMENT OF SIGNIFICANCE: This is the first review that focusses on the favorable potential of monetite for hard tissue repair and regeneration. The article accurately covers the "Synthesis-Structure-Property-Applications" correlations elaborating on monetite's diverse material properties. Special focus is put on the in vitro and in vivo properties of the material highlighting monetite as an orthopedic material-of-choice. The synthesis techniques are discussed which provide important information about the different fabrication routes for monetite. Most importantly, the review provides comprehensive knowledge about the diverse biomedical applications of monetite as granules, defect--specific scaffolds, bone cements and implant coatings. This review will help to highlight monetite's potential as an effective regenerative medicine and catalyze the continuing translation of this bioceramic from the laboratory to clinics.


Subject(s)
Orthopedics , Phosphates , Bone Cements , Calcium Phosphates
2.
Int J STD AIDS ; 29(11): 1142-1145, 2018 11.
Article in English | MEDLINE | ID: mdl-29749877

ABSTRACT

This national audit of 142 clinics demonstrated that the majority of clinics surveyed had policies and agreed clinical practice for alcohol and recreational drug enquiry, as well as documentation of HIV test refusal, although this was not the case in 24% of clinics as regards alcohol usage, 21% of clinics as regards recreational drugs use and 43% of clinics as regards chemsex usage. Regarding management of HIV test refusal, there was no policy or agreed practice in 13% of clinics with respect to men having sex with men (MSM) attenders, and in 18% of clinics for heterosexual attenders. Seventy percent of clinics had HIV point of care tests (POCT) available. Recommendations include: all clinics should have a policy of routine enquiry about alcohol, recreational drugs and chemsex, all clinics should record reasons for HIV test refusal and all clinics should provide testing alternatives to improve uptake, e.g. point of care testing or home sampling.


Subject(s)
Clinical Audit , HIV Infections , Health Policy , Homosexuality, Male , Illicit Drugs/adverse effects , Practice Guidelines as Topic , Ambulatory Care Facilities , Guideline Adherence , HIV Infections/diagnosis , HIV Infections/prevention & control , Humans , Male , Reproductive Health , Risk Assessment , Sexual Health , United Kingdom
3.
J Phys Chem B ; 121(5): 975-983, 2017 02 09.
Article in English | MEDLINE | ID: mdl-28032998

ABSTRACT

The intramembrane cytochrome bc1 complex of the photosynthetic bacterium Rhodobacter capsulatus and the cytochrome b6f complex, which functions in oxygenic photosynthesis, utilize two pairs of b-hemes in a symmetric dimer to accomplish proton-coupled electron transfer. The transmembrane electron transfer pathway in each complex was identified through the novel use of heme Soret band excitonic circular dichroism (CD) spectra, for which the responsible heme-heme interactions were determined from crystal structures. Kinetics of heme reduction and CD amplitude change were measured simultaneously. For bc1, in which the redox potentials of the transmembrane heme pair are separated by 160 mV, heme reduction occurs preferentially to the higher-potential intermonomer heme pair on the electronegative (n) side of the complex. This contrasts with the b6f complex, where the redox potential difference between transmembrane intramonomer p- and n-side hemes is substantially smaller and the n-p pair is preferentially reduced. Limits on the dielectric constant between intramonomer hemes were calculated from the interheme distance and the redox potential difference, ΔEm. The difference in preferred reduction pathway is a consequence of the larger ΔEm between n- and p-side hemes in bc1, which favors the reduction of n-side hemes and cannot be offset by decreased repulsive Coulombic interactions between intramonomer hemes.


Subject(s)
Coordination Complexes/chemistry , Cytochromes/metabolism , Electron Transport , Heme , Animals , Circular Dichroism , Crystallography, X-Ray , Cytochromes/chemistry , Electron Transport Complex III/chemistry , Heme/chemistry , Humans , Kinetics , Membranes/metabolism , Models, Molecular , Oxidation-Reduction , Signal Transduction
5.
Int J STD AIDS ; 23(2): 138-9, 2012 Feb.
Article in English | MEDLINE | ID: mdl-22422691

ABSTRACT

Penile cancer, albeit an uncommon malignancy, commonly affects men aged between 50 and 70 years, often with a history of predisposing factors such as Bowen's disease or leukoplakia. We describe a case of early invasive squamous cell carcinoma of the penis in a 39-year-old man with no history of predisposing factors, treated by a partial glansectomy.


Subject(s)
Carcinoma, Squamous Cell/diagnosis , Penile Neoplasms/diagnosis , Adult , Carcinoma, Squamous Cell/pathology , Carcinoma, Squamous Cell/surgery , Histocytochemistry , Humans , Male , Penile Neoplasms/pathology , Penile Neoplasms/surgery
6.
Zoonoses Public Health ; 58(2): 77-84, 2011 Mar.
Article in English | MEDLINE | ID: mdl-19912603

ABSTRACT

The growth kinetics of virulence plasmid-bearing Yersinia pseudotuberculosis (YPST) in sterile ground beef were studied at temperatures ranging from 0 to 30°C. In irradiated sterile ground beef, YPST replicated from 0 to 30°C, with corresponding growth rates (GR) ranging from 0.023 to 0.622 log CFU/h at 0-25°C, and the GR was 0.236 log CFU/h at 30°C. The maximum population densities (MPD) ranged from 8.7 to 11.0 log CFU/g. The growth and MPD of YPST were reduced significantly at 30°C. Models for GR and MPD of YPST in raw ground beef (RGB) as a function of storage temperatures were produced and displayed acceptable bias and accuracy. The models were validated with rifampicin-resistant YPST (rif-YPST) in sterile ground beef stored at 4, 10 and 25°C. The observed GR and MPD were within 95% of the predicted values. When compared to non-sterile retail ground beef, the growth of rif-YPST was not inhibited and displayed similar GR at 0, 10 and 25°C and MPDs as sterile ground beef at 10 and 25°C. Moreover, there was no loss of virulence plasmid in YPST during its growth in ground beef indicating that RGB contaminated with virulence plasmid-bearing YPST could cause disease due to refrigeration failure, temperature (10-25°C) abuse, and if the meat was not properly cooked.


Subject(s)
Cold Temperature , Meat Products/microbiology , Models, Biological , Yersinia pseudotuberculosis/growth & development , Yersinia pseudotuberculosis/pathogenicity , Animals , Cattle , Colony Count, Microbial , Consumer Product Safety , Food Contamination/analysis , Food Contamination/prevention & control , Humans , Kinetics , Plasmids , Population Growth , Virulence , Yersinia pseudotuberculosis Infections/transmission , Yersinia pseudotuberculosis Infections/veterinary
8.
Int J STD AIDS ; 20(5): 351-4, 2009 May.
Article in English | MEDLINE | ID: mdl-19386974

ABSTRACT

A national audit of sexual history-taking was conducted in genitourinary medicine clinics in the UK in 2008. Data were aggregated by region and clinic, allowing practice to be compared between regions, as well as to national averages and against national Guidelines. In this paper the case-notes of 4121 patients were audited. A high proportion of the case-notes were deemed to be completely legible. In other respects there is considerable inter-regional variation in the adherence to national Guidelines. Interventions are especially required to improve documentation of practice in discussing condom use, HIV risk assessment, offer of a chaperone and assessment for hepatitis B vaccination and hepatitis C testing, and issues concerning sexual contacts.


Subject(s)
Guideline Adherence , Medical Audit , Practice Guidelines as Topic , Sexual Behavior , Sexually Transmitted Diseases/diagnosis , Adolescent , Adult , Aged , Female , Humans , Male , Middle Aged , Patient Compliance , United Kingdom
9.
Int J STD AIDS ; 20(5): 355-7, 2009 May.
Article in English | MEDLINE | ID: mdl-19386975

ABSTRACT

Provision of a confidential, private environment for sexual history-taking was provided in almost all clinics. However, less than half of the clinics had a policy displayed about their confidentiality policy in waiting areas, although more had this available by other means. About two-thirds of clinic information/advertising literature included information about the need to take a sexual history. Sixty percent of clinics assessed clinician communication skills as part of service quality. Most clinics had policies relating to patients whose first language is not English, but only around half of clinics had policies for hearing difficulties and learning difficulties. Policies are also lacking in some clinics for documentation of the offer of chaperones and assessment of the competency of under-16-year-olds to consent to history-taking and examination.


Subject(s)
Guideline Adherence , Health Policy , Medical Audit , Practice Guidelines as Topic/standards , Sexual Behavior , Sexually Transmitted Diseases/diagnosis , Confidentiality , Female , Humans , Male , Sexually Transmitted Diseases/prevention & control , United Kingdom
10.
Int J STD AIDS ; 19(12): 856-8, 2008 Dec.
Article in English | MEDLINE | ID: mdl-19050219

ABSTRACT

SUMMARY: The aim of this study is to investigate the success of partner notification (PN) among 13 genitourinary medicine centres in West Midlands. The West Midlands Audit Group conducted a regional audit between June and August 2007. Information on screening and management of patients with chlamydia, gonorrhoea, early syphilis and HIV were collected separately. Participating centres were asked to provide PN details for 10 index patients with each of chlamydia, gonorrhoea, early syphilis and HIV infections. For each index patient with chlamydia or gonorrhoea, 0.54 and 0.44 partners were screened, respectively. Among partners of patients with syphilis and HIV, 24% and 35% were screened, respectively. Only 9% of 311 screened partners were involved in casual partnerships with index patients. Acquisition of more robust targets for PN, better documentation, improved communication between genitourinary (GU) medicine centres, and provider referral may improve the performance of PN for Sexually transmitted infections.


Subject(s)
Ambulatory Care Facilities , Contact Tracing , HIV Infections/prevention & control , Medical Audit , Sexual Partners , Sexually Transmitted Diseases, Bacterial/prevention & control , Contact Tracing/statistics & numerical data , HIV Infections/diagnosis , HIV Infections/epidemiology , Humans , Sexually Transmitted Diseases, Bacterial/diagnosis , Sexually Transmitted Diseases, Bacterial/epidemiology , United Kingdom
11.
Sex Transm Infect ; 84(4): 312-7, 2008 Aug.
Article in English | MEDLINE | ID: mdl-18586861

ABSTRACT

OBJECTIVE: This study examines the distribution of selected sexually transmitted infections (STIs) in older people (aged >/=45 years) attending genitourinary medicine (GUM) clinics in the West Midlands, UK. METHODS: Analysis of data from the regional enhanced STI surveillance system for the period 1996-2003. Selected STIs were chlamydia, genital herpes, genital warts, gonorrhoea and syphilis. RESULTS: Altogether, 4445 STI episodes were reported among older people during the study period. Between 1996 and 2003 older people accounted for 3.7% and 4.3%, respectively, of all GUM clinic attendances. The rate of STIs in older people more than doubled in 2003 compared with 1996 (p<0.0001). Rates for all five selected diagnoses were significantly higher in 2003 compared to 1996. A significantly increasing trend over time was seen overall (p<0.0001) and for each of the selected diagnoses. Overall, males and those aged 55-59 years of age were significantly more likely to be affected. CONCLUSIONS: This study provides evidence of significant increases in attendance at GUM clinics by older people. Although it is recognised that young people should remain the focus of sexual health programmes, the results indicate that sexual risk-taking behaviour is not confined to young people but also occurs among older people. There is therefore a need to develop and implement evidence-based multifaceted sexual health programmes that while aiming to reduce STI transmission among all age groups should include interventions aimed specifically at older people and address societal and healthcare attitudes, myths and assumptions about sexual activity among older people.


Subject(s)
Sexually Transmitted Diseases/epidemiology , Age Distribution , Aged , Aged, 80 and over , England/epidemiology , Female , Humans , Male , Middle Aged , Sex Distribution
12.
Int J STD AIDS ; 18(10): 717-9, 2007 Oct.
Article in English | MEDLINE | ID: mdl-17945054

ABSTRACT

The potential complications of pelvic inflammatory disease (PID) make optimizing its management a high priority. A clinical audit of PID against current national management guidelines was conducted in 14 departments of genitourinary medicine in the West Midlands for women presenting with PID between January and December 2005. There were a total of 810 diagnoses of PID made from a total of 49,390 female attendees for that year, giving an incidence of 164 cases per 10,000 attendees. Of these 810 cases, data collection and analysis for this audit were performed on 139. An ofloxacin 400 mg twice daily (b.i.d.) based regimen was prescribed in 91 (65%, 95% confidence interval [CI] 57-73%) cases. Doxycycline 100 mg b. i. d. for 14 days plus metronidazole 400 mg b. i. d. for 5-14 days was prescribed in 44 (32%, 95% CI 25-40%) cases, but a third-generation cephalosporin was only given with this regimen in three cases. Partner notification was performed in 101 (73%, 95% CI 65-79%) cases. A total of 130 male contacts were recorded on the data collection forms, and of these 58 (45%) were traced and 51 (39%), treated. A follow-up appointment was given to 133 (96%, 95% CI 91-98%) women, although in most cases this was for seven days or more, and 104 (78%, 95% CI 67-81%) women attended for follow-up. Adherence to the national guidelines in this cohort of patients did not reach the national standard for choice of treatment regimen nor did it attain the target for proportion of male partners traced. Barriers preventing adherence to the national guidelines need to be explored and appropriate assistance given to physicians to help meet national standards of care.


Subject(s)
Anti-Bacterial Agents/therapeutic use , Health Services Research , Pelvic Inflammatory Disease/drug therapy , Anti-Bacterial Agents/administration & dosage , Contact Tracing/statistics & numerical data , Female , Guideline Adherence/statistics & numerical data , Humans , Incidence , Male , Pelvic Inflammatory Disease/epidemiology , Pelvic Inflammatory Disease/prevention & control , United Kingdom/epidemiology
15.
Clin Nephrol ; 64(2): 113-23, 2005 Aug.
Article in English | MEDLINE | ID: mdl-16114787

ABSTRACT

AIM: To determine whether extended epoetin alfa dosing schedules of up to once every four weeks are as effective as weekly dosing in maintaining hemoglobin (Hb) levels in patients with anemia of chronic kidney disease (CKD). METHODS: This randomized, open-label trial enrolled patients with anemia of CKD not on dialysis. Patients were required to have a stable Hb level (> or = 11.0 g/dl) and to have been previously receiving epoetin alfa for two or more months. Patients were randomized to one of four subcutaneously administered epoetin alfa dosing regimens: 10,000 units (U) once weekly (QW), 20,000 U every two weeks (Q2W), 30,000 U every three weeks (Q3W) or 40,000 U every four weeks (Q4W). Dose reductions, but not escalations, were permitted. Patients received treatment for a total of 16 weeks. The primary endpoint for the trial was the mean final Hb measurements of the QW, Q2W, Q3W, and Q4W groups. The primary efficacy analyses were non-inferiority assessments of the mean final Hb measurements of the Q2W, Q3W, and Q4W groups, compared with the QW group. The primary efficacy analyses were performed using a modified intent-to-treat (MITT) population, defined as all patients meeting all inclusion/exclusion criteria (or, if not satisfying all criteria, were granted an exemption at study entry), and who were randomized and received at least one dose of study medication. A per-protocol population, based on all patients who met the MITT criteria and completed the entire study, was used to evaluate the robustness of the MITT results. Quality of life was assessed for all dosing groups throughout the study. Safety was based on all patients randomized who received at least one dose of study medication. RESULTS: A total of 519 patients were enrolled; 445 were included in the MITT population. The four treatment groups were comparable with respect to baseline characteristics. The primary etiologies of CKD were diabetes (45.7%) and hypertension (29.9%). The mean baseline Hb, serum creatinine and glomerular filtration rate for all patients were 11.9 +/- 0.8 g/dl, 3.1 mg/dl, and 21.1 ml/min/1.73 m2, respectively. The mean baseline transferrin saturation was 25.2% and the mean ferritin was 201.9 ng/ml for all patients. All groups had a mean final Hb of > 11.0 g/dl. The mean final Hb levels of the Q2W and Q4W groups were statistically non-inferior to the QW group. The results of the per-protocol analysis were consistent with the MITT results. In addition, 93.5%, 89.5%, 77.2%, and 76.0% of patients maintained a mean Hb > or = 11.0 g/dl throughout the course of the study in the QW, Q2W, Q3W, and Q4W groups, respectively. Quality of life was maintained or improved from baseline to final within each dosing group. There were no significant differences in the mean final quality of life scores between the QW group and the Q2W, Q3W, and Q4W groups. Among the 513 patients evaluated for safety, epoetin alfa was well tolerated with no differences in adverse events between groups. The incidence of thrombotic adverse events was low (2.5% of patients), as was mortality (1.4% of patients). CONCLUSIONS: Approximately 90% of patients dosed once every two weeks and over 75% of patients dosed once every three or four weeks maintained mean Hb levels > or = 11.0 g/dl, consistent with the Kidney Disease Outcomes Quality Initiative (K/DOQI) guidelines. This study suggests that extended epoetin alfa dosing schedules are effective and safe for maintaining Hb, and may offer the possibility of increased flexibility and convenience for the majority of patients with the anemia of CKD.


Subject(s)
Anemia/drug therapy , Erythropoietin/administration & dosage , Hematinics/administration & dosage , Kidney Failure, Chronic/complications , Aged , Analysis of Variance , Anemia/etiology , Epoetin Alfa , Female , Humans , Male , Middle Aged , Prospective Studies , Quality of Life , Recombinant Proteins , Treatment Outcome
16.
Int J STD AIDS ; 16(7): 512-4, 2005 Jul.
Article in English | MEDLINE | ID: mdl-16004636

ABSTRACT

We report a case of Crohn's disease where the patient initially presented with vulval ulceration to the gynaecology unit. Initial investigations were planned jointly by both the gynaecology and genitourinary medicine staff. An examination under general anaesthetic by both teams was performed and biopsies taken. These showed a chronic inflammatory process with epithelioid granulomas. The teams then referred the case to the dermatology team who made the diagnosis of vulval Crohn's disease and initiated treatment with prednisolone and azathioprine. The case illustrates the need for a multi-speciality approach when dealing with such cases.


Subject(s)
Crohn Disease/complications , Crohn Disease/diagnosis , Vulvar Diseases/diagnosis , Vulvar Diseases/etiology , Adult , Cooperative Behavior , Crohn Disease/pathology , Dermatology , Female , Female Urogenital Diseases , Gynecology , Humans , Medicine , Specialization , Vulva/pathology , Vulvar Diseases/pathology
17.
J Mater Sci Mater Med ; 15(2): 145-50, 2004 Feb.
Article in English | MEDLINE | ID: mdl-15330048

ABSTRACT

To be successful, an implant should be biocompatible, strong and contain surface pores to promote osseointegration. A one-step microwave sintering procedure of titanium powders was attempted in this work. The idea was to take advantage of the peculiar way microwave couple with metallic powders, i.e. generating heat in the interior of the sample and dissipating it away through the surface. This non-conventional heating of titanium powder produced a dense core with surface porosity. The dense core provides the strength while the surface pores promote bone growth. The experiments were carried out in a semi-industrial grade microwave cavity using a alpha-SiC susceptor. Power levels of 1-1.5 kW, and soaking periods of approximately 30 min were used. Microstructural characterization was carried out by a scanning electron microscope. The sintered titanium had gradient porosity on the surface with a thickness of about 100-200 microm depending on the microwave power. The pores were interconnected with size ranging from 30 to 100 microm. This kind of microstructure is favorable for cell growth. Tensile strength values as high as 400 MPa were obtained for these samples.


Subject(s)
Dental Implants , Titanium/chemistry , Microscopy, Electron, Scanning/methods , Porosity , Surface Properties , Thermodynamics
18.
Commun Dis Public Health ; 7(2): 112-9, 2004 Jun.
Article in English | MEDLINE | ID: mdl-15259411

ABSTRACT

Sexually transmitted infections (STIs) declined in the UK during the 1980s and early 1990s but have increased substantially since 1995. Within the overall increase there are important differences in the epidemiology of these infections. The current, aggregate system of STI data collection in the UK provides limited demographic information and is unable to fully explain these differences. More useful information can be obtained using an enhanced surveillance system that collects disaggregate, anonymised, individual patient data including ethnic group and truncated postcode of residence. Such a system has been set up in the West Midlands NHS region. The methodology of the project is described here along with the findings to date. These findings confirm that the burden of STIs disproportionately affects young persons, men who have sex with men, black ethnic minority groups and those living in urban areas. Identifying the groups at greatest risk in this way enables interventions to be more usefully targeted.


Subject(s)
Population Surveillance , Public Health Informatics , Sexually Transmitted Diseases/epidemiology , Adolescent , Adult , Ambulatory Care Facilities/statistics & numerical data , Anonymous Testing , Confidentiality , Databases, Factual , England/epidemiology , Female , Humans , Male , Sexuality , Sexually Transmitted Diseases/classification , Sexually Transmitted Diseases/ethnology
20.
Phys Rev Lett ; 89(19): 197201, 2002 Nov 04.
Article in English | MEDLINE | ID: mdl-12443142

ABSTRACT

The one-body tunnel picture of single-molecule magnets (SMMs) is not always sufficient to explain the measured tunnel transitions. An improvement to the picture is proposed by including also two-body tunnel transitions such as spin-spin cross relaxation (SSCR) which are mediated by dipolar and weak superexchange interactions between molecules. A Mn4 SMM is used as a model system. At certain external fields, SSCRs lead to additional quantum resonances which show up in hysteresis loop measurements as well-defined steps. A simple model is used to explain quantitatively all observed transitions.

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