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In the current study, Ni0.4Cu0.2Zn0.4Fe2−4xSn3xO4 (Sn → NiCuZn) (x ≤ 0.10) nanospinel ferrites (NSFs) have been fabricated by a citrate sol–gel approach, and their structure, morphology, and magnetic features were investigated via XRD, SEM with EDX, HR-TEM, TEM, and VSM, respectively. Their cubic spinel phase was endorsed from their Rietveld refinement. The products' DXRD (crystallite sizes) were estimated within the 36–69 nm range. The 10 and 300 K magnetization measurements show ferromagnetic and superparamagnetic behaviors, respectively. The saturation magnetization (Ms) decreases at both temperatures with increasing Sn ratio up to x = 0.06 into the lattice of NSFs but thereafter rises with the additional rise of Sn ratio from 0.06 to 0.10. The alterations of Ms values with Sn substitution have been deliberated via cation redistribution, and changes in the anisotropy constant. Hc value at 10 K almost initially increased for lower Sn content and then decreased at higher Sn content. The coercivity is in reverse proportionality to the particle/crystallite size and domain wall movement of ferromagnetism. [ABSTRACT FROM AUTHOR]

Human T Lymphotronic Virus type 1 was the first retrovirus discovered associated with fatal diseases in humans and said to have emerged following zoonotic transmission from simian populations. Their primary target is adult CD4 T-cells and most infected individuals are asymptomatic. However, a significant number may develop persistent infection and progress to an aggressive lymphoproliferative disease, known as Adult T-cell Leukemia/Lymphoma-ATLL. Some may develop a debilitating neuro-inflammatory disease called Tropical Spastic Paraparesis-TSP, predominantly involving the lower limbs, with or without hyperactive urinary bladder. Unprotected sexual intercourse and breastfeeding account for the highest number of cases and is also transmitted by uncheck blood transfusion or sharing of contaminated sharps. ATLL and TSP are life-threatening diseases initially restricted to Middle East and some parts of Africa, but recently, cases are being reported in many parts of the world. Unfortunately, even though the antiretroviral therapy have greatly improved and significantly reduced HIV progression to AIDS, such great break through is not worthy benefit for HTLV infected individuals. Thus, they are identified as severe human diseases of public health concern. This review is an overview and contains update about the biology of the virus, its interaction with the host, HAM/TSP and ATLL; their epidemiology and clinical presentations.

The Ho3+ ion-substituted SrBa nanohexaferrites, Sr0.5Ba0.5Fe12−xHoxO19 (x ≤ 0.1) (Ho → SrBa NHFs), were fabricated via ultrasonic-assisted sol–gel route. The hexagonal structure and plate-like morphology were confirmed by X-ray powder pattern (XRD), transmittance electron microscope (TEM), scanning electron microscope (SEM), and high-resolution transmittance electron microscope (HR-TEM). It has been found out that the crystallite size (DXRD) was within 45–74 nm range. Both elemental mapping and energy-dispersive X-ray spectroscopy (EDX) analyses provided the purity and expected chemical composition of the products. Using the M–H hysteresis loops (at 300 and 10 K), magnetic properties of Ho → SrBa NHFs are analyzed. Upon a sudden fall at x = 0.02, as soon as Ho ions are added, the magnetization is improved with the Ho substitution and prominently enhanced with decreasing temperature. However, the coercivity Hc is decreased with the Ho substitution. The Ho-doped samples represent a magnetically soft material at both high and low temperatures, which is also confirmed through M–T measurements. Their squareness ratio is found to be less than 0.5, suggesting the generation of multi-magnetic domains. The unsubstituted HFs and the samples with x = 0.02 and 0.06 show usual M–T variations with typical field-cooling (FC) and zero-field-cooling (ZFC) branches. However, the other samples (with x = 0.04, 0.08, and 0.10) exhibit unusual behavior with anomalies in their M–T plots. From 57Fe Mössbauer spectroscopy data, the variation in line width, isomer shift, quadrupole splitting, and hyperfine magnetic field values on Ho3+ substitution have been determined. Mössbauer spectra show that Ho3+ ions located at generally octahedral 12 k site. The s-electron density of around Fe3+ ions has not influenced doped content. [ABSTRACT FROM AUTHOR]

Ni0.8Cu0.1Zn0.1MoxFe2–2xO4 (x ≤ 0.1) nanospinel ferrites (Mo → NiCuZn NSFs) were produced by sol–gel approach. A spinel structure formation with no impurities was confirmed by X-ray diffraction (XRD) patterns. The nanoparticles' morphology and chemical composition of the products have been confirmed via SEM, TEM, HR-TEM, and EDX. By fitting Mössbauer spectra at RT, Hyperfine parameters were determined. A superparamagnetic state was observed in all samples. The Mo4+ were found to reside in the B site mainly. Isomer shift values showed that Mössbauer spectra composed magnetic Fe3+ sextets. Magnetic characteristics of Mo → NiCuZn NSFs are probed employing hysteresis loops at 300 K and 10 K. The significant role of Mo ions in the magnetic characteristics of the host material is revealed by employing saturation magnetization (Ms), magnetic moment ( n B ), coercivity (Hc), SQR (squareness ratio), and magneto-crystalline anisotropy constant. While the samples show a superparamagnetic behavior at 300 K, they represent a magnetically soft material at 10 K. The magnetic parameters, with a minimum magnetization at x = 0.06, fluctuate with respect to Mo concentration at each temperature. The Ms and nB become the maximum for the Mo → NiCuZn NSFs (x = 0.02) which yields the minimum Hc. The SQR is negligible at 300 K and low (much less than 0.5) at 10 K, reflecting the generation of multi-magnetic domains and a relatively low anisotropy field. [ABSTRACT FROM AUTHOR]

Since the eradication of smallpox approximately 39 years ago, monkeypox virus remains the most pathogenic poxvirus, being mainly restricted to Central and West Africa. Before 1970, there were no reports of human monkeypox in Nigeria, while between 1971 and 1978 there were three cases, with none having been reported thereafter. However, in September 2017, a case of contagious skin rash disease, typical of monkeypox, was observed in an 11‐year‐old boy from the southern part of the country and confirmed to be associated with the monkeypox virus. This large outbreak consisted of 262 suspected, 115 confirmed cases, and 7 mortalities across 26 states and the Federal Capital Territory (FCT), Abuja. The aim of this manuscript is to provide an updated, comprehensive, and timely review of monkeypox, an important emerging infection in Nigeria. Monkeypox is now a major threat to global health security, requiring an urgent multidisciplinary approach involving veterinarians, physicians, virologists, and public health experts to fast‐track the development of diagnostic assays, vaccines, antivirals, and other control strategies. [ABSTRACT FROM AUTHOR]

Barium hexaferrite is a well-known hard magnetic material. Doping using nonmagnetic cation such as Zn were found to enhance magnetization owing to preferential tetrahedral site (4 f ) occupancy of the zinc. However, the distribution of cations in hexaferrites depends on many factors such as the method of preparation, nature of the cation, and chemical composition. Here, Zn-doped barium hexaferrites (BaZnFeO) were synthesized by sol-gel method. In this study, we summarized the magnetic properties of BaZnFeO ( x = 0, 0.1, 0.2, 0.3) BaM, investigated by Mössbauer spectroscopy. Moreover, cation distribution was also calculated for all the products. Mössbauer parameters were determined from 57Fe Mössbauer spectroscopy and according to it, the replacement of Ba-Zn affects all parameters such as isomer shift, the variation in line width, hyperfine magnetic field, and quadrupole splitting. Cation distribution revealed the relative area of undoped BaM, 12 k, 2 a, and 4 f positions which are close to theoretical values. [ABSTRACT FROM AUTHOR]

To study the effect of Zn substitution on structural magnetic properties and hyperfine interactions of barium hexaferrite, BaFeZnO (0.0≤ x≤0.3) hexaferrites were synthesized via sol-gel auto-combustion technique. Rietveld analysis of XRD powder patterns confirmed the formation of single-phase hexaferrites for all products. Due to the larger ionic size of Zn as compared with Fe, while x increases, the lattice constant parameters increase to a small degree. Nanoplate morphology of the products is presented by SEM analyses. It was observed that both saturation magnetization and coercivity decrease in almost the same manner with zinc concentration for all substitutions. Cation distribution calculations showed that Zn occupies 12 k, 4 f , 4 f , and 2 b sites and at the same time pushes Fe ions towards 2 a and 12 k sites. FromFe Mössbauer spectroscopy data, the variation in line width, isomer shift, quadrupole splitting, and hyperfine magnetic field values on Zn substitution have been determined. [ABSTRACT FROM AUTHOR]

Diagnostic virology is of great importance particularly in disease management and for epidemiological purposes, but is slow and results are obtained when the patient has recovered or succumbed to the infection. In addition, consideration of antiviral chemotherapy is in short supply even where preliminary investigation results are available. Some viruses are highly unculturable, fastidious or hazardous to the laboratory personnel and diagnosis depends on serological methods or culture in an expensive bio-safety level. Molecular diagnostic techniques do not depend on pathogen isolation or growth or on the detection of an immune response to the pathogen, rather uses genotypic characteristics to identify specific pathogen. Nucleic acid of a given pathogen is unique, and therefore nucleic acid analysis can be used for unequivocal identification via amplification to increase the amount of material available for analysis. Nucleic acid-based diagnostic methods are extremely sensitive, reliable and to some extent affordable, and are widely used for clinical microbiology to detect pathogen. [ABSTRACT FROM AUTHOR]

Cervical cancer is the most common female cancer in northern Nigeria, yet the pattern of infection with human papillomavirus, the principal aetiologic agent is unknown. This was a preliminary study conducted in two referral hospitals in order to establish base-line data on the prevalence and risk factors for the infection in Kano state, Nigeria. Fifty (50) randomly selected women aged 18 years and above were recruited from gynaecology clinics in Murtala Muhammad Specialist Hospital and Aminu Kano teaching Hospital. Relevant sexual and socio-demographic information were obtained from each subject using a questionnaire. Exfoliated cervical cells were harvested and processed using Polymerase Chain Reaction to identify the DNAs of high-risk HPV types 16 and 18. The prevalence rate of HPV infection was 76% [(38/50) at 95% CI=61.8-86.9] with 60.5% (23/38) having co-infections with both HPV type 16 and 18. Risk factors of the infection include low literacy level; living in rural settlements; low parity; early menarche (<15 years of age); early onset of first sexual intercourse (⩽16 years of age) and multiple sexual partners. There was however, no statistically significant association between oral contraceptive usage and acquisition of the infections. Findings of this study suggest a high prevalence of HPV types 16 and 18 among women attending gynaecology clinic in Kano and thus called for more elaborate community based study in order to establish the magnitude of the problem from wider perspective. [ABSTRACT FROM AUTHOR]

With the changing paradigm in disease trends, Nigeria may be faced with serious challenges in terms of healthcare and disease management. Cervical cancer, which is one of the cancers that is vaccine preventable, remain the most frequently reported and the leading cause of mortality from cancer in Nigeria. More than 36.59 million women are at risk and 26 die of the disease on daily basis. The country is currently ranked the worse place to be a woman with cancer in Africa, yet there is nothing to write home about in terms of preparedness. Every year huge amount of money is released but little or nothing gets done. There is urgent need for immediate action, especially with the advent of the three promising prophylactic vaccines, to be more pro-active, in controlling the menace of cervical cancer in the country. Cervical cancer should be given same priority as HIV/AIDs, Tuberculosis, Malaria and Childhood immunizations. [ABSTRACT FROM AUTHOR]