Solid-State Synthesis of POPD@AgNPs Nanocomposites for Electrochemical Sensors.

In the present work, Poly(o-phenylenediamine) (POPD) stabilized silver nanoparticles (POPD@AgNPs) nanocomposites was synthesized by solid state oxidative polymerization method using o-phenylenediamine dihydrochloride (oPD-HCl) as monomer and silver nitrate (AgNO3) used as metal precursor as well as oxidizing agent no other external oxidizing agent was used. POPD@AgNPs nanocomposites were characterized by various instrumental techniques to confirm their size, shape and its composition. The electrocatalytic activity of POPD and POPD@AgNPs modified electrode was investigated over the oxidation of hydrazine (N2H4) and reduction of hydrogen peroxide (H2O2) using Cyclic Voltammetry (CV), Differential Pulse Voltammetry (DPV) and Chronoamperometry techniques. POPD and POPD@AgNPs were characterized using HR-TEM, FE-SEM, XRD, UV-Visible, FT-IR, Micro Raman spectroscopy and those results were confirmed their chemical purity, particle size, shape and its elemental compositions. Moreover, the DPV and chronoamperometry reveals that POPD@AgNPs is a good sensor for the electrochemical gas detection of N2H4 and H2O2 because it has good stability, easy-operation, excellent reproducibility, high sensitivity and good limit of detection when compared to with pure POPD. This system shows good stability, excellent sensitivity, response and the detection limit was obtained for the detection of N2H4 and H2O2 in trace level gases, which was lower than some of the modified electrodes.

Zinc oxide epitaxial thin film deposited over carbon on various substrate by pulsed laser deposition technique.

Zinc Oxide (ZnO) is a promising candidate material for optical and electronic devices due to its direct wide band gap (3.37 eV) and high exciton binding energy (60 meV). For applications in various fields such as light emitting diode (LED) and laser diodes, growth of p-type ZnO is a prerequisite. ZnO is an intrinsically n-type semiconductor. In this paper we report on the synthesis of Zinc Oxide-Carbon (ZnO:C) thin films using pulsed laser deposition technique (PLD). The deposition parameters were optimized to obtain high quality epitaxial ZnO films over a carbon layer. The structural and optical properties were studied by glazing index X-ray diffraction (GIXRD), photoluminescence (PL), optical absorption (OA), and Raman spectroscopy. Rutherford backscattering spectroscopy (RBS), scanning electron microscopy with energy dispersive spectroscopy (SEMEDS) and atomic force microscopy (AFM) were employed to determine the composition and surface morphology of these thin films. The GIXRD pattern of the synthesized films exhibited hexagonal wurtzite crystal structure with a preferred (002) orientation. PL spectroscopy results showed that the emission intensity was maximum at -380 nm at a deposition temperature of 573 K. In the Raman spectra, the E2 phonon frequency around at 438 cm(-1) is a characteristic peak of the wurtzite lattice and could be seen in all samples. Furthermore, the optical direct band gap of ZnO films was found to be in the visible region. The growth of the epitaxial layer is discussed in the light of carbon atoms from the buffer layer. Our work demonstrates that the carbon is a novel dopant in the group of doped ZnO semiconductor materials. The introduction of carbon impurities enhanced the visible emission of red-green luminescence. It is concluded that the carbon impurities promote the zinc related native defect in ZnO.

Primary non-Hodgkins lymphoma of the ovary in the background of human immunodeficiency virus (HIV): a bold and curative approach to treatment.

Non-Hodgkins lymphoma of the ovary is a rare disease and there is only one previously documented case arising in a patient with human immunodeficiency virus (HIV). In this report, the authors discuss the management of a case of non-Hodgkins Lymphoma of the ovary occurring in a patient with HIV and demonstrate that treatment regimens may be successfully implemented in this immunocompromised population without an increase in adverse effects.

Human papillomavirus (HPV)-type distribution in relation to oral contraceptive use in women with cervical intraepithelial neoplasia, Durban, South Africa.

OBJECTIVE: To determine HPV-type distribution among women with cervical dysplasia in relation to oral contraceptive usage. METHODS: Prospective cross-sectional study of four groups of patients according to oral contraceptive usage: non-users, users of less than five years duration, users of between five years and ten years, and users of more than ten years duration. Swabs of the cervix were analysed for HPV DNA using the polymerase chain reaction method. RESULTS: A total of 124 women were recruited for the study. There were 75 patients who were HIV-infected (seroprevalence 61%). There were 102 patients who were HPV positive (82%), of which 79 patients had high-risk HPV DNA (78%). In terms of the four oral contraceptive groups, high-risk HPV DNA was detected in 70% (n = 21), 79% (n = 22), 90% (n = 21) and 71% (n = 15) of patient, respectively. The odds of having HPV DNA was six times higher for the combination of contraceptive users of less than five years duration/non-users (OR 5.9, 95% CI: 1.87-18.77). There was no change when adjustment was made for age (OR 6.1, 95% CI: 1.9-19.4). HPV DNA type 16 and/or 18 was present in a total of 21 patients (49%) (non-contraceptive users and users < 5 years duration) versus 15 patients (42%) (oral contraceptive users of more than 5 years duration) (p = 0.524). HPV type 16 was the commonest HPV type detected (20.2%) and HPV type 58 was the next commonest hihg-risk HPV type (16.1%). HPV types 58 and 33 were detected in a much greater percentage of our population and HPV 16 in a much smaller percentage of our population compared with a non-South African population. CONCLUSION: The findings of this study demonstrate an interesting distribution of HPV types in a South African population.

Remarkable thermal conductivity enhancement in Ag-decorated graphene nanocomposites based nanofluid by laser liquid solid interaction in ethylene glycol.

We report on the synthesis and enhanced thermal conductivity of stable Ag-decorated 2-D graphene nanocomposite in ethylene glycol based nanofluid by laser liquid solid interaction. A surfactant free nanofluid of Ag nanoparticles anchored onto the 2-D graphene sheets were synthesized using a two-step laser liquid solid interaction approach. In order to understand a pulsed Nd:YAG laser at the fundamental frequency (λ = 1,064 nm) to ablate Ag and graphite composite target submerged in ethylene glycol (EG) to form AgNPs decorated 2-D GNs-EG based nanofluid. From a heat transfer point of view, it was observed that the thermal conductivity of this stable Ag-graphene/EG is significantly enhanced by a factor of about 32.3%; this is highest reported value for a graphene based nanofluid.

Trends of histopathology of cervical cancer among women in Durban, South Africa.

INTRODUCTION: Cervical squamous cell carcinoma has traditionally been the commonest histological type of cervical cancer. Adenocarcinoma has recently been reported to occur with increasing frequency. METHODS: This retrospective study was conducted on 2,930 patients with cervical cancer over an eight-year period (1995-2002) recruited from the combined Gynaecology Oncology Clinic at King Edward VIII Hospital (KEH), Pathology Laboratories at KEH, and from the private sector. RESULTS: In the public sector squamous cell carcinoma was found to be the commonest type of cervical cancer irrespective of ethnicity and age. It was found to occur in over 80% of patients and remained fairly static over the time period. In the private sector, a slightly higher proportion (38.8%) of women had adenocarcinoma, however since the total number of patients were small (85) there was no statistically significant increase in adenocarcinoma relative to squamous cell carcinoma. There was no correlation between the documented risk factors i.e., smoking, contraception and human papillomavirus and histological type of cervical cancer. Similarly, there was no statistically significant relationship between ethnicity, differentiation, type of cervical cancer and age of the patient in both sectors. CONCLUSION: This study has not revealed an increasing incidence in cervical adenocarcinoma in the public setting. However, in the private sector, a significant proportion of black women (38.8%) had adenocarcinoma. All Asian women had adenocarcinoma while 25% of the white women had adenocarcinoma. Although the total number of patients in this group are small (85), these results cannot be ignored.

Data Centre Profile: The Provincial Health Data Centre of the Western Cape Province, South Africa.

INTRODUCTION: The Western Cape Provincial Health Data Centre (PHDC) consolidates person-level clinical data across government services, leveraging sustained investments in patient registration systems, a unique identifier, and maturation of administrative and clinical digital health systems. OBJECTIVES: The PHDC supports clinical care directly through tools for clinicians which integrate patient data or identify patients in need of interventions, and indirectly through supporting operational and epidemiological analyses. METHODS: The PHDC is housed entirely within government. Data are processed from a range of source systems, usually daily, through distinct harmonisation and curation, beneficiation, and reporting processes. Linkage is predominantly through the unique identifier which doubles as a pervasive folder number, augmented by other identifiers. Further data processing includes triangulation of multiple data sources for enumerating health conditions, with assignment of certainty levels for each enumeration. Outputs include patient-specific email alerts, a web-based consolidated patient clinical viewing platform, filterable line-listings of patients with specific conditions and associated characteristics and outcomes, management reports and dashboards, and data releases in response to operational and research data requests. Strict architectural, administrative and governance processes ensure privacy protection. RESULTS: In the past decade 8 million unique people are recorded as having sought healthcare in the provincial public sector health services, with current utilisation at 15 million attendances or admissions a year. Cross-sectional enumeration of health conditions includes over 430 000 people with HIV, 500 000 with hypertension, 235 000 with diabetes. Annually 110 000 pregnancies and 54 000 patients with tuberculosis are enumerated. Over 50 data requests are processed each year for internal and external requesters in accordance with data request and release governance processes. CONCLUSIONS: The single consolidated environment for person-level health data in the Western Cape has created new opportunities for supporting patient care, while improving the governance around access to and release of sensitive patient data.

Placental site trophoblastic tumor with antecedent molar pregnancy in association with human immunodeficiency virus infection.

The occurrence of placental site trophoblastic tumor (PSTT) is rare. PSTT following molar pregnancy is uncommon. The report describes the presentation of PSTT following molar pregnancy in the background of human immunodeficiency virus infection.

Round worm infestation as a cause of small bowel anastomotic breakdown following urinary diversion for cervical cancer.

BACKGROUND: Vesicovaginal fistulae are well-recognized complications of radiotherapy for the treatment of cervical cancer. These patients often require some form of urinary diversion. Small bowel is often utilized for these purposes. CASE: A patient with stage IIB cervical cancer presented with a vesicovaginal fistula 6 years post-radiotherapy. An ileal conduit was performed. On day 9 post-surgery breakdown of the small bowel anastomosis was suspected. At laparotomy small bowel anastomotic breakdown was confirmed with round worms at the anastomotic site. CONCLUSION: Perforation of small bowel by round worm has been previously described in a patient with Meckel' s diverticulum. This report describes an unusual cause of small bowel anastomotic breakdown following urinary diversion.

The impact of anticancer activity upon Beta vulgaris extract mediated biosynthesized silver nanoparticles (ag-NPs) against human breast (MCF-7), lung (A549) and pharynx (Hep-2) cancer cell lines.

The present study tried for a phyto-synthetic method of producing silver nanoparticles (Ag-NPs) with size controlled as and eco-friendly route that can lead to their advanced production with decorative tranquil morphology. By inducing temperature fluctuation of the reaction mixture from 25 to 80°C the plasmon resonance band raised slowly which had an ultimate effect on size and shape of Ag-NPs as shown by UV-visible spectroscopy and TEM results. The biosynthesized nanoparticles showed good cytotoxic impact against MCF-7, A549 and Hep2 cells compared to normal cell lines. Compared to control plates, the percentage of cell growth inhibition was found to be high with as concentrations of Ag-NPs becomes more as determined by MTT assay. The AO/EtBr staining observations demonstrated that the mechanism of cell death induced by Ag-NPs was due to apoptosis in cancer cells. These present results propose that the silver nanoparticles (Ag-NPs) may be utilized as anticancer agents for the treatment of various cancer types. However, there is a need for study of in vivo examination of these nanoparticles to find their role and mechanism inside human body. Further, studies we plan to do biomarker fabrication from the green synthesized plant extract nanoparticles like silver, gold and copper nanoparticles with optimized shape and sizes and their enhancement of these noble nanoparticles.

The effects of a polyacrylamide-derived water treatment residue on the hydraulic conductivity, water retention and evaporation of four contrasting South African soils and implications for land disposal.

Water treatment residue (WTR), a by-product from the production of potable water, was traditionally disposed of to landfill but there is growing interest in applying this waste to land as an alternative disposal option. Because WTR consists mainly of flocculated fine silt and clay, there is concern that should the residue decompose back to its original constituents, there is an adverse risk for soil water storage and transmission properties of soil. In a laboratory study, four different soil types were amended with a polyacrylamide WTR at rates ranging from 0 to 1280 Mg ha(-1). The treatments were evaluated for changes in water retention, hydraulic conductivity and evaporation. The results showed that WTR decreased bulk density and evaporation and actually increased hydraulic conductivity and water retention, mainly because of the sustained performance of the polymer in binding the silt and clay into gravel-sized aggregates. Such changes were, however, only significant at the 1280 Mg ha(-1) application rate. Therefore, very large amounts of WTR would have to be applied in order to markedly change these inherent physical properties of the soils. In view of this finding, the land treatment of WTR appears possible.

Charge Carrier Transport Mechanism Based on Stable Low Voltage Organic Bistable Memory Device.

A solution processed two terminal organic bistable memory device was fabricated utilizing films of polymethyl methacrylate PMMA/ZnO/PMMA on top of ITO coated glass. Electrical characterization of the device structure showed that the two terminal device exhibited favorable switching characteristics with an ON/OFF ratio greater than 1 x 10(4) when the voltage was swept between - 2 V and +3 V. The device maintained its state after removal of the bias voltage. The device did not show degradation after a 1-h retention test at 120 degrees C. The memory functionality was consistent even after fifty cycles of operation. The charge transport switching mechanism is discussed on the basis of carrier transport mechanism and our analysis of the data shows that the charge carrier trans- port mechanism of the device during the writing process can be explained by thermionic emission (TE) and space-charge-limited-current (SCLC) mechanism models while erasing process could be explained by the FN tunneling mechanism. This demonstration provides a class of memory devices with the potential for low-cost, low-power consumption applications, such as a digital memory cell.

Ovarian carcinoma, pericardial metastasis and human immunodeficiency virus infection.

As the AIDS epidemic increases at an alarming proportion, there is a greater likelihood of finding gynecological malignancies in HIV-positive females. The clinician is therefore faced with management and ethical dilemmas, as the most appropriate management in this setting is unknown. This case report illustrates both an unusual site of pericardial metastasis in a patient with HIV infection and ovarian carcinoma. The management of the pericardial tamponade is also described.

Mannitol in neonatal cerebral oedema.

Twenty-five full term severely asphyxiated newborn babies with cerebral oedema were divided into 2 groups and treated on a randomised basis with either Mannitol or no Mannitol. We report our findings and conclude that Mannitol is of no benefit in the management of cerebral oedema in severely asphyxiated term infants.

Microsatellite analysis of early stage (Ia-IIb) uterine cervical squamous carcinoma.

Cervical cancer is the most common gynecologic malignancy of the developing world. The oncogenic role of human papilloma virus (HPV) is well known. Attention is now focusing on the complicit genetic changes, which allow progression of these tumors. Regarding these changes, deletion of tumor suppressor genes (loss of heterozygosity [LOH]) is the preferred pathway of progression with only a subset manifesting microsatellite instability (MSI). Implicated loci include 3p14.1-22. Several studies suggest that the mutator phenotype in cervical cancer may correlate with higher grade tumors, more advanced disease stage, and poor outcome. Unlike colorectal cancer, in which an inverse relationship has been demonstrated between microsatellite instability and loss of heterozygosity, cervical cancers expressing MSI have been found to coexpress LOH at other loci. In this study we analyzed 8-microsatellite loci including p53, DCC, APC, the MMR gene hMLH1 and 2 regions of interest on chromosome 3 in a high-risk population group in which HPV infection is endemic.

Use of the nested reverse transcription-polymerase chain reaction for the detection of human papillomavirus 16 E6 transcriptional activity in cervical cancer: a technical perspective.

AIM: The aim of this study was to evaluate HPV 16 E6 expression using nested RT-PCR in cervical tumour tissue and compare this technique with standard RT-PCR in a group of patients using injectable contraceptive steroids. PATIENTS AND METHODS: Tumour DNA was analysed for the presence and type of HPV by polymerase chain reaction (PCR) from 120 cervical cancer samples. Ribonucleic acid (RNA) was extracted from cervical tissue samples and cell-lines. Reverse transcription was carried out on all samples using reverse transcriptase enzyme to form single-stranded cDNA. The GAPDH (glyceraldehyde-3-phosphate dehydrogenase) housekeeping gene was used. RESULTS: The majority of patients had squamous cell carcinoma. Of 120 cervical tissue samples, there were 111 samples with confirmed HPV 16 infection. RNA was extracted in only 86 samples. Of these, 23 samples contained genomic DNA. Of the remaining 63 patients, there were 53 patients who had expression of HPV-type 16. E6 full-length gene expression. In total there were 25 patients (40%) with expression of the HPV 16 E6*I gene and 30 patients with expression of the E6*II gene. The nested PCR method using S1/S2 primers detected 54 patients with the E6*I & E6*II transcripts in comparison to classical PCR which detected only 31 such transcripts. CONCLUSION: Nested RT-PCR is the method of choice to determine the role of different E6/E7 splice products in HPV-associated carcinogenesis.

Anal sphincter reconstruction for incontinence due to non-obstetric sphincter damage.

OBJECTIVE: To assess the outcome after anal sphincteroplasty in patients with anal incontinence following non-obstetric anal sphincter damage. DESIGN: A prospective study carried out in an urban teaching hospital over five years (1994-1998). PATIENTS AND METHODS: Fourteen patients, median age of 30 years, all undergoing anal sphincter reconstruction. The procedure was performed under general or regional anaesthesia. Operative management was (i) excision of the scar tissue and apposition of the cut ends of the sphincter or (ii) a reefing technique. RESULTS: Sphincter damage was as a result of trauma in nine cases, haemorrhoidectomy in two cases, sepsis in two and failed recto-vaginal fistula repair in one case. In six patients with traumatic sphincter damage a colostomy was performed at original operation. The other eight presented with incontinence, four of whom required a diverting colostomy prior to repair. The median delay between sphincter injury and repair was six months (range 4-120). The posterior approach was used in eight patients, an anterior approach in five and both approaches in one. Non-absorbable suture material was used in six and absorbable material was used in eight patients. Twelve of the 14 patients had scar tissue at the site of damage requiring excision. Two post-haemorrhoidectomy patients underwent the reefing technique. Eleven patients (79%) were completely continent after initial repair. Two required further repair resulting in complete continence. One patient remained with mild incontinence. CONCLUSION: Anal sphincter reconstruction for non-obstetric anal incontinence produced good short-term results.

Physiotherapists and human immunodeficiency virus/acquired immune deficiency syndrome: knowledge and prevention: a study in Durban, South Africa.

This study determined what physiotherapists in Durban, South Africa know about human immunodeficiency virus (HIV)/acquired immune deficiency syndrome (AIDS), their attitudes towards patients and how they cope as individuals. Data were collected using a validated questionnaire. One-hundred-and-fourteen physiotherapists in Durban hospitals participated in the study. Seventy-two per cent of the questionnaires met the criteria for analysis. Ninety per cent of the participants believed that they knew about HIV/AIDS, but only 78% could identify all viral transmission modes. Of the 38 physiotherapists who believed that they knew the stages of an HIV infection, only 11% actually knew the stages, 28% could not explain them and 61% were vaguely aware. Fifty-six per cent of the respondents had treated patients who had died from HIV/AIDS. Only 38% of physiotherapists were completely at ease when treating HIV/AIDS patients despite the fact that 98% believed that physiotherapy was an integral component of the management of an AIDS patient. Fifty-one per cent of the respondents were unaware of support structures provided by their employers. The authors conclude that the perceptions of physiotherapists about their knowledge about HIV/AIDS do not stand up to scrutiny. Significantly more attention should be paid to the development, implementation and evaluation of the effectiveness of educational programmes on HIV/AIDS for physiotherapists in the workplace.

Dysphagia secondary to tuberculous lymphadenitis.

Oesophageal tuberculosis is a rare entity often pre-disposed to by caseating tuberculous mediastinal lymphadenopathy (TML). Although widely reported in children, TML is an under appreciated entity in adults; in this article dysphagia in an adult patient caused by TML is described.

The morphometry and morphology of the foramen magnum in age and sex determination within the south african black population utilizing computer tomography (CT) scans / Morfometría y morfología del foramen magnum en la determinación de edad y sexo dentro de la población negra sudafricana mediante tomografía computarizada (TC)

SUMMARY: The morphology and morphometry of the foramen magnum aid forensic studies in identifying unknown individuals according to age and sex. Moreover, these parameters of the foramen magnum have clinical relevance to surgeons in the transcondylar approach. This study aimed to analyze the morphometry and morphology in relation to the age and sex of individuals within the South African Black population, utilizing computerized tomography images. The use of computerized tomography images allowed for accurate morphometric diameters using the SLICER 3-D software version 4.7.0. Radiological images also provide a patient's clinical history. Thus, the process of exclusion in respect to patients with pathological conditions of the skull is achieved. The sample studied included 150 computerized tomography images (93 males and 57 females) arranged according to age cohorts (children aged 1-12 years, adolescents aged 13-17 years and adults aged 18-25 years). The morphometric parameters viz. antero-posterior diameter, transverse diameter and area of the foramen magnum was analyzed in relation to age and sex. The morphological variations of the foramen magnum was simultaneously observed between males and females and within the age groups. The objective of this study were to improve data on the morphological and morphometric parameters of the foramen magnum in the South African Black population. This study also attempted to associate the morphological and morphometric parameters of the foramen magnum with age and sex determination.

RESUMEN: La morfología y morfometría del foramen magnum ayuda a los estudios forenses en la identificación de individuos desconocidos según la edad y el sexo. Además, parámetros del foramen magnum tienen relevancia clínica para los cirujanos en el abordaje transcondilar. Este estudio tuvo como objetivo analizar la morfometría y la morfología del foramen magnum, en relación con la edad y el sexo, dentro de la población negra sudafricana, utilizando imágenes de tomografía computarizada. El uso de imágenes de tomografía computarizada permitió definir diámetros morfométricos precisos utilizando el software SLICER 3-D versión 4.7.0. Las imágenes radiológicas también proporcionan antecedentes de la historia clínica de un paciente. De este modo, se logra el proceso de exclusión con respecto a los pacientes con afecciones patológicas del cráneo. La muestra estudiada incluyó 150 imágenes de tomografía computarizada (93 hombres y 57 mujeres) organizadas según cohortes de edad (niños de 1 a 12 años, adolescentes de 13 a 17 años y adultos de 18 a 25 años). Los parámetros morfométricos que se consideraron fueron: diámetro antero-posterior, diámetro transversal y área del foramen magnum. Las variaciones morfológicas del foramen magnum se observaron simultáneamente entre hombres y mujeres y dentro de los grupos de edad. El objetivo de este estudio fue mejorar los datos sobre los parámetros morfológicos y morfométricos del foramen magnum en la población negra sudafricana. Este estudio también intentó asociar los parámetros morfológicos y morfométricos del foramen magnum con la determinación de la edad y el sexo.