RESUMEN
Staphylococcus aureus is a common bacterial pathogen known to cause various kinds of infections due to its repertoire of virulence factors. This study aimed to investigate the distribution of 19 types of virulence genes among clinical isolates of methicillin-susceptible S. aureus (MSSA) using the polymerase chain reaction. A total of 109 MSSA isolates, i.e., 63 hospital-associated (HA) and 46 community-associated (CA) were collected from Hospital Sultanah Nur Zahirah, the main tertiary hospital in Terengganu, Malaysia, from July 2016 to June 2017. The most frequent virulence genes detected were hla (78.9%, n=86) and hld (78.0%, n=85) encoding hemolysins, lukED (56.9%, n=62) encoding leukotoxin ED, followed by seb (26.6%, n=29) and sea (24.8%, n=27) encoding enterotoxins. Among 34 (31.2%) isolates carrying six or more virulence genes, only five were multidrug resistant (MDR) while the remaining isolates were susceptible. Significant associations were discovered between the hld gene with CA-MSSA (p=0.016) and the seo gene with HA-MSSA (p=0.023). However, there is no significant association between virulence genes among the different types of infection. The clinical MSSA isolates in Terengganu showed high prevalence and high diversity of virulence gene carriage.
Asunto(s)
Infecciones Comunitarias Adquiridas , Infección Hospitalaria , Infecciones Estafilocócicas , Staphylococcus aureus , Factores de Virulencia , Malasia , Humanos , Infecciones Estafilocócicas/microbiología , Infecciones Estafilocócicas/epidemiología , Factores de Virulencia/genética , Infecciones Comunitarias Adquiridas/microbiología , Infecciones Comunitarias Adquiridas/epidemiología , Staphylococcus aureus/genética , Staphylococcus aureus/patogenicidad , Staphylococcus aureus/aislamiento & purificación , Staphylococcus aureus/efectos de los fármacos , Infección Hospitalaria/microbiología , Infección Hospitalaria/epidemiología , Persona de Mediana Edad , Femenino , Masculino , Adulto , Anciano , Virulencia/genética , Adulto Joven , Niño , Adolescente , Antibacterianos/farmacología , PreescolarRESUMEN
INTRODUCTION: Blood culture contamination remains a dilemma issue in the diagnosis of bloodstream infection. However, to date, there is no national data on blood culture contamination and the common organism isolated in Malaysia. This is a pioneer multi-centre study involving public hospitals with medical microbiologists in Malaysia to determine the blood culture contamination rate and the common organism isolated. MATERIALS AND METHODS: This retrospective cross-sectional study involved record review of all blood culture results over 9 months period from 1st January 2018 until 30th September 2018 in 27 government hospitals in Malaysia. For each positive culture result, the type of isolated organism was classified to represent true bacteraemia or contamination. RESULTS: We analysed 448,109 blood culture records from the participating hospitals. The blood culture positivity rate was 12.5% (57395 of 448109) and 25.0% (14367 of 57395) of the positive blood culture represents contamination. The national blood culture contamination rate in Malaysia was 3.2%. The contamination rate in the adult population was significantly higher than the paediatric population (3.6% vs. 2.6%; p<0.001). The blood contamination rate by institution ranged from 1.5% to 6.8%. The most frequently isolated microorganisms in the contaminated cultures were coagulase-negative staphylococci (71.0%). CONCLUSION: Blood culture contamination is a major issue that warrants priority in recognition, and interventions should be implemented to reduce the blood contamination rate in Malaysia.
Asunto(s)
Bacteriemia , Cultivo de Sangre , Hospitales Públicos , Humanos , Malasia , Estudios Retrospectivos , Estudios Transversales , Bacteriemia/microbiología , Bacteriemia/diagnóstico , Adulto , Niño , Femenino , Masculino , Persona de Mediana EdadRESUMEN
Frank-Ter Haar syndrome (FTHS) is a rare genetic hereditary autosomal recessive disorder characterized by defective malformation of cardiovascular, craniofacial, and skeletal system. Mutations in the SH3PXD2B gene are a common cause in the development of FTHS. We recruited a family with two affected individuals (3-year-old female and 2-month-old male infant) having bilateral clubfoot. Family pedigree shows an autosomal recessive mode of inheritance. DNA was extracted from the blood samples of six members of the family. Whole exome sequencing was done for the two affected individuals and the variant was validated in the whole family by using Sanger sequencing approach. Whole exome sequencing (WES) data analysis identified a rare homozygous variant (c.280C>G; p.R94G) in the SH3PXD2B gene, and Sanger sequencing showed that the same variant perfectly segregates with the phenotype in the pedigree. Moreover, the variant is predicted to be damaging and deleterious by several computation tools. Revisiting the family members for detailed clinical analysis, we diagnosed the patients as having the typical phenotype of FTHS. This study enabled us to correctly diagnose the cases of FTHS in a family initially recruited for having bilateral clubfoot by using WES. Moreover, this study identified a novel homozygous missense variant (c.280C>G; p.R94G) in (NM_001308175.2) the SH3PXD2B gene as a causative variant for autosomal recessive FTHS. This finding supports the evidence that homozygous mutations in the SH3PXD2B gene are the main cause in the development of FTHS.
RESUMEN
@#Staphylococcus aureus is a common bacterial pathogen known to cause various kinds of infections due to its repertoire of virulence factors. This study aimed to investigate the distribution of 19 types of virulence genes among clinical isolates of methicillin-susceptible S. aureus (MSSA) using the polymerase chain reaction. A total of 109 MSSA isolates, i.e., 63 hospital-associated (HA) and 46 community-associated (CA) were collected from Hospital Sultanah Nur Zahirah, the main tertiary hospital in Terengganu, Malaysia, from July 2016 to June 2017. The most frequent virulence genes detected were hla (78.9%, n=86) and hld (78.0%, n=85) encoding hemolysins, lukED (56.9%, n=62) encoding leukotoxin ED, followed by seb (26.6%, n=29) and sea (24.8%, n=27) encoding enterotoxins. Among 34 (31.2%) isolates carrying six or more virulence genes, only five were multidrug resistant (MDR) while the remaining isolates were susceptible. Significant associations were discovered between the hld gene with CA-MSSA (p=0.016) and the seo gene with HA-MSSA (p=0.023). However, there is no significant association between virulence genes among the different types of infection. The clinical MSSA isolates in Terengganu showed high prevalence and high diversity of virulence gene carriage.
RESUMEN
INTRODUCTION: The sensorineural acuity level (SAL) test was developed as an alternative assessment to estimate bone conduction (BC) thresholds in cases where masking problems occur in pure tone audiometry (PTA). Nevertheless, prior to its clinical application, the respective SAL normative data must be made available. As such, the present study was carried out to establish SAL normative data using an insert earphone and two different commercially available bone transducers. Additionally, to determine the effect of earphone type on SAL test results, it was also of interest to compare the present study's findings with those of a previous study (that used a headphone to derive SAL normative data). MATERIALS AND METHODS: In this repeated-measures study, 40 Malaysian adults (aged 19-26 years) with normal hearing bilaterally (based on PTA results) were enrolled. They then underwent the SAL test based on the recommended protocol by Jerger and Tillman (1960). The SAL normative data for each ear were obtained by calculating the differences between air conduction (AC) thresholds in quiet and AC thresholds in noise by means of insert earphone, B71 and B81 bone vibrators. RESULTS: The SAL normative values were comparable between the ears (p > 0.05), and the data were pooled for subsequent analyses (n = 80 ears). Relative to B81 bone transducer, B71 bone vibrator produced statistically higher SAL normative data at all frequencies (p < 0.05). The SAL normative values established by the present study were statistically lower than those of the previous study (that utilised headphones) at most of frequencies tested (p < 0.05). CONCLUSIONS: The SAL normative data produced by the two bone vibrators were significantly different. The SAL normative values were also affected by the type of earphone used. While conducting the SAL test on Malaysian patients, the information provided by this study can be useful to guide the respective clinicians in choosing the appropriate normative data.
Asunto(s)
Audiometría , Pruebas Auditivas , Adulto , Humanos , Audiometría/métodos , Umbral Auditivo , Pruebas Auditivas/métodos , Conducción Ósea , TransductoresRESUMEN
BACKGROUND: Middle East respiratory syndrome coronavirus (MERS-CoV) was identified in humans in 2012. Since then, 2605 cases and 937 associated deaths have been reported globally. Camels are the natural host for MERS-CoV and camel to human transmission has been documented. The relationship between MERS-CoV shedding and presence of neutralizing antibodies in camels is critical to inform surveillance and control, including future deployment of camel vaccines. However, it remains poorly understood. The longitudinal study conducted in a closed camel herd in Egypt between December 2019 and March 2020 helped to characterize the kinetics of MERS-CoV neutralizing antibodies and its relation with viral shedding. RESULTS: During the 100-day longitudinal study, 27 out of 54 camels (50%) consistently tested negative for presence of antibodies against MERS-CoV, 19 (35.2%) tested positive and 8 (14.8%) had both, positive and negative test results. Fourteen events that could be interpreted as serological indication of probable infection (two seroconversions and twelve instances of positive camels more than doubling their optical density ratio (OD ratio) in consecutive samples) were identified. Observed times between the identified events provided strong evidence (p = 0.002) against the null hypothesis that they occurred with constant rate during the study, as opposed to clustering at certain points in time. A generalized additive model showed that optical density ratio (OD ratio) is positively associated with being an adult and varies across individual camels and days, peaking at around days 20 and 90 of the study. Despite serological indication of probable virus circulation and intense repeated sampling, none of the tested nasal swab samples were positive for MERS-CoV RNA, suggesting that, if the identified serological responses are the result of virus circulation, the virus may be present in nasal tissue of infected camels during a very narrow time window. CONCLUSIONS: Longitudinal testing of a closed camel herd with past history of MERS-CoV infection is compatible with the virus continuing to circulate in the herd despite lack of contact with other camels. It is likely that episodes of MERS-CoV infection in camels can take place with minimal presence of the virus in their nasal tissues, which has important implications for future surveillance and control of MERS-CoV in camel herds and prevention of its zoonotic transmission.
Asunto(s)
Infecciones por Coronavirus , Coronavirus del Síndrome Respiratorio de Oriente Medio , Animales , Humanos , Coronavirus del Síndrome Respiratorio de Oriente Medio/genética , Camelus , Estudios Longitudinales , Infecciones por Coronavirus/epidemiología , Infecciones por Coronavirus/veterinaria , Anticuerpos NeutralizantesRESUMEN
Although young-onset colorectal cancer (CRC) is commonly linked to genetic predispositions such as Lynch syndrome, there has been an increasing trend in the prevalence of sporadic type youngonset CRC. We highlighted two cases of young patients diagnosed with CRC. Both patients came at the late stage of presentation with right sided colon tumour and local lymph nodes involvement. Loss of MLH1 expression with positive BRAF V600E was seen on immunohistochemistry staining. Additionally, they have no chronic disease or familial history of malignancy. The follow-up surveillance CT scan and the surveillance colonoscopy of case 1 showed no local recurrence and distant metastasis. However, another patient defaulted on the subsequent follow-up. In this report, we review the clinicopathological characteristics of these two cases and discuss the importance of the screening for the BRAF V600E and the four MMR proteins to characterise the sporadic and hereditary subgroups of young-onset CRC.
Asunto(s)
Neoplasias Colorrectales Hereditarias sin Poliposis , Neoplasias Colorrectales , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/patología , Neoplasias Colorrectales Hereditarias sin Poliposis/diagnóstico , Neoplasias Colorrectales Hereditarias sin Poliposis/epidemiología , Neoplasias Colorrectales Hereditarias sin Poliposis/genética , Reparación de la Incompatibilidad de ADN , Predisposición Genética a la Enfermedad , Humanos , Inmunohistoquímica , Persona de Mediana Edad , Homólogo 1 de la Proteína MutL/genética , Proteínas Proto-Oncogénicas B-raf/genéticaRESUMEN
In the Kinabatangan floodplain, Sabah, Malaysian Borneo, oil palm and settlements have reduced and fragmented lowland tropical forests, home to around 200 endangered Bornean elephants (Elephas maximus borneensis). In this region, elephants range within forests, oil palm and community areas. The degree to which elephants are using these areas remains unclear. We used GPS telemetry data from 2010 to 2020 for 14 collared elephants to map their entire known ranges and highly used areas (hot spots) across four land use categories and estimate time spent within these. The use of land use types across elephants varied significantly. Typically, females had strong fidelity to forests, yet many of these forests are threatened with conversion. For the three males, and several females, they heavily used oil palm estates, and this may be due to decreased landscape permeability or foraging opportunities. At the pooled level, the entire range and hot spot extents, constituted 37% and 34% for protected areas, respectively, 8% and 11% for unprotected forests, 53% and 51% for oil palm estates, and 2% for community areas. Protecting all forested habitats and effectively managing areas outside of protected areas is necessary for the long-term survival of this population.
Asunto(s)
Elefantes , Animales , Borneo , Conservación de los Recursos Naturales , Ecosistema , Femenino , Bosques , Malasia , MasculinoRESUMEN
BACKGROUND: The Gulf Centralised Committee for Drug Registration (GCC-DR), as part of the Gulf Health Council (GHC), enables the consolidated registration of pharmaceutical products throughout the member states of the Gulf Cooperation Council. OBJECTIVES: The objectives of this study were to provide an update of the performance of the GCC-DR centralised procedure; evaluate the review times for new products submitted to the GCC Centralised Registration between January 2015 and December 2020; assess the impact of applying facilitated regulatory pathways and implementing a reliance strategy; identify the strengths and weaknesses of the centralised review process; and propose strategies that could enhance the GCC regulatory review process leading to improved access to medicines for patients. METHODS: A standardised data collection template enabled the structured documentation of information collected by the Senior Regulatory Affairs and Regulatory Affairs Specialists from the Executive Board of the Health Ministers Council for GCC States to determine the GHC structure, resources, review models and milestones and timelines. The total number of applications approved was provided together with the average yearly timelines for new active substances and generics from January 2015 to December 2020 including both scientific assessment time from the agency as well as applicant response time to questions raised. Actual approval times for each product were calculated from the date of submission to the date of approval. RESULTS: The fewest (58) new products were approved in 2019 and the most (200) in 2020. The average review times for new medicines were the longest (838 calendar days) in 2015 and the shortest (321 calendar days) in 2019. Important changes recently implemented include an increase in the number of GCC-DR meetings, adoption of a standardised electronic common technical document and GCC regulatory review template, removal of authorisation dependence on pricing agreements and introduction of a reliance strategy. Additional recommendations include Executive Committee mandates for dossier review, target times for dossier validation, scientific review and Expert Committee recommendation and training for quality decision making. CONCLUSIONS: GCC procedures and decision-making processes have been positively influenced by a variety of expert reviewers, unified guidelines and the implementation of a reliance strategy. Certain barriers must still be overcome to enhance the quality of the review, and to shorten regulatory review times without compromising the scientific robustness of the review.
RESUMEN
Pontine infarct is a rare but clinically significant cause of an isolated facial nerve palsy. Prompt diagnosis with the use of magnetic resonance imaging (MRI) allows early initiation of treatment for such patients. We report a 62-year-old gentleman with diabetes, hypertension, and gout, presenting with lower motor neuron facial nerve palsy. This report highlights that isolated facial nerve palsy is not always associated with Bell's palsy, which remains the commonest cause of facial nerve paralysis. A thorough neurological examination and good clinical correlation with the patient's history and physical findings, coupled with the use of facial nerve anatomical knowledge and early employment of MRI, are imperative in clinching the diagnosis.
Asunto(s)
Parálisis de Bell , Parálisis Facial , Accidente Cerebrovascular , Parálisis de Bell/complicaciones , Parálisis de Bell/diagnóstico , Parálisis Facial/diagnóstico , Parálisis Facial/etiología , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/diagnósticoRESUMEN
The self-healing of bio-concrete cracks and pores have been utilised worldwide to improve the properties of bio-concrete using different types of bacteria. Meanwhile, no published research was conducted to heal bio-foamed concrete bricks (B-FCB) pores using Bacillus tequilensis. Previous studies focused on the concentration of bacteria and neglect other factors that could affect the healing process. This research aimed to optimise the healing ratio of B-FCB pores using four factors: B. tequilensis concentration, concrete density, temperature and CO2 concentration. Initial water absorption (IWA) and water absorption (WA) were used as responses in statistical methods, namely, factorial and response surface methodology (RSM). B. tequilensis species was isolated from cement kiln dust, produced in a powder form, then subjected to simulate test using a special medium consisting of foamed concrete materials to check the survival ability in B-FCB. SEM, EDX, and XRD were used to investigate the healing process of B-FCB pores. The results revealed that the decrement ratios of IWA and WA of B-FCB were 52.8% and 29.1% compared to FCB, respectively. SEM results reflect the healing that occurred in B-FCB pores, mostly healed via precipitation of CaCO3 as demonstrated on the XRD results.
RESUMEN
Fiber optical parametric amplifiers (FOPAs) operating based on four-wave mixing (FWM) are versatile devices with increasing applications in optical communication systems. In this paper, the effects of dispersion fluctuations on the performance of bandwidth, ripple, parametric gain, and saturation power of a two-pump FOPA based on four-wave and six-wave models are studied and compared. Coupled-amplitude equations representing the non-degenerate FWM process in optical fiber are solved numerically to compute the parametric gain over the communication wavelengths. The behaviors of the performance parameters are critically analyzed and compared with different types of fluctuation strengths (or amplitudes) specified by the combinations of correlation length (Lc) and fluctuation amplitude (σ). Based on the results, it was found that the flat gain bandwidth for the four-wave model remains unchanged and is insensitive to the strengths of fluctuations. The gain ripples, however, get higher as the fluctuation strengths increase. On the other hand, the flat gain bandwidths of the six-wave model are hardly identified due to the tremendous and continuous ripples within the pump wavelengths. In addition, the minimum parametric gain values for both four-wave and six-wave models reduce as the fluctuation strengths increase. Also, the lowest value of parametric gain leads to the highest saturation power and vice versa. The dispersion fluctuations affect the FWM process's efficiency and deteriorate the overall amplifier performance, particularly for the six-wave model. The numerical analysis obtained via the six-wave model is especially useful since this model closely matches with practical circumstances.
RESUMEN
World Health Organization (WHO) reported that over 1.5 billion people are infected by soil-transmitted helminths (STH) worldwide in sub-Saharan Africa, the United States of America, China, and East Asia. Heavy infections and polyparasitism are associated with higher morbidity rates, and the patients are exposed to increased vulnerability to other diseases. Therefore, accurate diagnosis followed by mass treatment for morbidity control is necessary.STH diagnosis commonly involves the microscopic observation of the presence of the STH eggs and larvae in the faecal samples. Furthermore, molecular approaches are increasingly utilised in monitoring and surveillance as they show higher sensitivity. Their capability to differentiate hookworm species is an advantage over the Kato-Katz technique. This review discusses the advantages and limitations of microscopy and various molecular tools used for STH detection.
RESUMEN
This research aimed to optimize the compressive strength of bio-foamed concrete brick (B-FCB) via a combination of the natural sequestration of CO2 and the bio-reaction of B. tequilensis enzymes. The experiments were guided by two optimization methods, namely, 2k factorial and response surface methodology (RSM). The 2k factorial analysis was carried out to screen the important factors; then, RSM analysis was performed to optimize the compressive strength of B-FCB. Four factors, namely, density (D), B. tequilensis concentration (B), temperature (T), and CO2 concentration, were selectively varied during the study. The optimum compressive strength of B-FCB was 8.22 MPa, as deduced from the following conditions: 10% CO2, 3 × 107 cell/mL of B, 27 °C of T and 1800 kg/m3 of D after 28 days. The use of B. tequilensis in B-FCB improved the compressive strength by 35.5% compared to the foamed concrete brick (FCB) after 28 days. A microstructure analysis by scanning electronic microscopy (SEM), energy dispersive X-ray (EDX) and X-ray diffraction analysis (XRD) reflected the changes in chemical element levels and calcium carbonate (CaCO3) precipitation in the B-FCB pores. This was due to the B. tequilensis surface reactions of carbonic anhydrase (CA) and urease enzyme with calcium in cement and sequestered CO2 during the curing time.
RESUMEN
Through the regional control programme, Malaysia has been successfully reducing the incidence of Plasmodium falciparum and Plasmodium vivax infections. However, the incidence of zoonotic malaria Plasmodium knowlesi infection is increasing and now has been the major cause of malaria in Malaysia especially Malaysian Borneo. The emergence of knowlesi infection has threatened the malaria elimination programme which the government aims to reduce the overall malaria infections by 2020. Unlike other benign human Plasmodium spp., P. knowlesi can cause fatal infections. The aim of this study was to determine the incidence and distribution of five human malaria parasites including P. knowlesi in Peninsular Malaysia and Malaysian Borneo. A total of 112 blood samples were collected from seven states and district hospitals in Peninsular Malaysia and Malaysian Borneo from year 2015 to 2016. The samples were examined by microscopy and further confirmed by nested PCR assay targeting 18S rRNA gene of Plasmodium spp. Following the nested PCR assays, a total of 54 (48.2%) samples were positive for P. knowlesi infections, 12 (10.7%) cases were positive for P. vivax infections, followed by 7 (6.3%) cases of P. falciparum and 4 (3.5%) cases of P. malariae. There were 3 cases (2.7%) of mixed infections (P. knowlesi/P. vivax). However, no cases were identified as P. ovale. A total of 32 (28.6%) cases were found as negative infections. LoopMediated Isothermal Amplification Assay (LAMP) was performed to confirm inconclusive results produced by microscopy and nested PCR. P. knowlesi showed the highest prevalence in Sarawak (n= 30), Sabah (n=13), Pulau Pinang (n=5) and Pahang (n=6). PCR and LAMP was not able to detect a large number of microscopy positive samples due to DNA degradation during storage and shipping. Among all the states involved in this study, the highest prevalence of P. knowlesi infection was found in Sabah and Sarawak.
Asunto(s)
Malaria , Plasmodium knowlesi , Hospitales , Humanos , Incidencia , Malaria/epidemiología , Malaria Falciparum , Malaria Vivax , Malasia/epidemiología , Plasmodium knowlesi/genética , Plasmodium knowlesi/aislamiento & purificaciónRESUMEN
International Academy of Pathology, Malaysian Division has initiated and run the external quality assurance program for general diagnostic histopathology since the year 2017. This article introduces the educational philosophy of this external quality assurance program and the technicalities in running such a national program. Challenges in ensuring the successful running of this program to gain wide acceptance by histopathology laboratories in Malaysia as well as experience in overcoming these challenges are detailed. This article charts the future direction of this external quality assurance program.
Asunto(s)
Laboratorios , Garantía de la Calidad de Atención de Salud , Humanos , MalasiaRESUMEN
OBJECTIVE: This study is a preliminary work to develop a Malay version questionnaire named 'Inventori Persepsi bagi Muslim yang Memiliki Masalah Pendengaran (IPM3P)' to assess the perception on Islamic understanding and practice among Muslim adults with hearing impairment. METHODS: The scale development involved three phases: i) generation of domains based on the literature, ii) generation of sub-domains based on literature review and Islamic panel survey, and iii) generation of items. RESULTS: Preliminary version of IPM3P consists of 59 items was produced, representing three domains: Obligation (18 items), Practice (21 items), and Difficulty (20 items), and seven sub-domains ('Ibadah', 'Aqidah', 'Muamalat', 'Tasawwuf', 'Akhlak','Da'wah', and 'Sirah'). CONCLUSION: The preliminary version of IPM3P needs to be psychometrically tested. This pioneering study may become an impetus towards more research pertaining to understanding the effect of hearing loss towards religious life in the future in Malaysia.
Asunto(s)
Pérdida Auditiva , Islamismo , Adulto , Humanos , Malasia , Encuestas y CuestionariosRESUMEN
@# Through the regional control programme, Malaysia has been successfully reducing the incidence of Plasmodium falciparum and Plasmodium vivax infections. However, the incidence of zoonotic malaria Plasmodium knowlesi infection is increasing and now has been the major cause of malaria in Malaysia especially Malaysian Borneo. The emergence of knowlesi infection has threatened the malaria elimination programme which the government aims to reduce the overall malaria infections by 2020. Unlike other benign human Plasmodium spp., P. knowlesi can cause fatal infections. The aim of this study was to determine the incidence and distribution of five human malaria parasites including P. knowlesi in Peninsular Malaysia and Malaysian Borneo. A total of 112 blood samples were collected from seven states and district hospitals in Peninsular Malaysia and Malaysian Borneo from year 2015 to 2016. The samples were examined by microscopy and further confirmed by nested PCR assay targeting 18S rRNA gene of Plasmodium spp. Following the nested PCR assays, a total of 54 (48.2%) samples were positive for P. knowlesi infections, 12 (10.7%) cases were positive for P. vivax infections, followed by 7 (6.3%) cases of P. falciparum and 4 (3.5%) cases of P. malariae. There were 3 cases (2.7%) of mixed infections (P. knowlesi/P. vivax). However, no cases were identified as P. ovale. A total of 32 (28.6%) cases were found as negative infections. LoopMediated Isothermal Amplification Assay (LAMP) was performed to confirm inconclusive results produced by microscopy and nested PCR. P. knowlesi showed the highest prevalence in Sarawak (n= 30), Sabah (n=13), Pulau Pinang (n=5) and Pahang (n=6). PCR and LAMP was not able to detect a large number of microscopy positive samples due to DNA degradation during storage and shipping. Among all the states involved in this study, the highest prevalence of P. knowlesi infection was found in Sabah and Sarawak.
RESUMEN
H2S gas when exposed to metal can be responsible for both general and localized corrosion, which depend on several parameters such as H2S concentration and the corrosion product layer formed. Therefore, the formation of passive film on 316L steel when exposed to H2S environment was investigated using several analysis methods such as FESEM and STEM/EDS analyses, which identified a sulfur species underneath the porous structure of the passive film. X-ray photoelectron spectroscopy analysis demonstrated that the first layer of CrO3 and Cr2O3 was dissolved, accelerated by the presence of H2S-Cl-. An FeS2 layer was formed by incorporation of Fe and sulfide; then, passivation by Mo took place by forming a MoO2 layer. NiO, Ni(OH)2, and NiS barriers are formed as final protection for 316L steel. Therefore, Ni and Mo play an important role as a dual barrier to maintain the stability of 316L steel in high pH2S environments. For safety concern, this paper is aimed to point out a few challenges dealing with high partial pressure of H2S and limitation of 316L steel under highly sour condition for the oil and gas production system.
RESUMEN
INTRODUCTION: Lymphoma of parapharyngeal space (PPS) is a rare condition. The clinical presentations may vary and often masquerades as infection or an inflammatory condition. A misdiagnosis will lead to a delay in treatment of the disease. Due to the complex anatomy of PPS, any attributed pressure from masses can lead to a life-threatening event such as cardiac syncope. CASE REPORT: We report a rare case of PPS B-cell non-Hodgkin lymphoma with superimposed Tuberculosis (TB) and fungal infection that presents with several episodes of syncope and hemodynamic depression. DISCUSSION: The clinical entities in PPS lesions syncope and its associated syndromes, pathophysiology, and differential diagnosis together with possible managements are further discussed.