Silver nanoparticles-based localized surface plasmon resonance biosensor for Escherichia coli detection

Escherichia coli (E. coli) bacteria with varying solution concentrations have been successfully detected using silver nanoparticles (Ag NPs)-based localized surface plasmon resonance (LSPR) biosensors. The Ag NPs were effectively synthesized by a chemical method using trisodium citrate with L-Histidine (L-His) and deposited on the surface of Au thin film-coated half-cylinder BK-7 prisms. He-Ne laser with a wavelength of 632.8 nm was used to generate LSPR phenomena in Kretschmann configuration with prism/Au thin film/His-Ag NPs/E. coli bacteria/air structure arrangements. The variation of E. coli bacteria concentration was carried out to determine the effect of E. coli bacteria concentration on the LSPR curve characteristics. The characterization results showed that the size of Ag NPs was 18.7 nm, and that of His-Ag NPs was 17.9 nm. Selected area electron diffraction results indicated the formation of diffraction rings with the presence of lattice planes (111), (200), (220), and (311), proving the face-centered cubic crystal structure of silver. The absorbance peak of Ag NPs shifted from a wavelength of 421-414 nm with an increase in band gap energy from 2.94 eV to 2.99 eV, along with a decreased average particle size. The functional groups observed in His-Ag NPs showed wavenumbers at 3320 to 3318 cm-1, 2106 to 2129 cm-1, and 1635 cm-1, showing the OH, CH, and C CO bonds, respectively. The SPR angle of the prism/Au thin film/air structure is 44.80°. Meanwhile, the LSPR angle for the prism/Au thin film/His-Ag NPs/air structure is 44.92°. There is an increase in the LSPR angle by 0.12°. Moreover, the minimum reflectance increases by 0.02. After detecting E. coli bacteria, the LSPR angle shifted by 0.26°, 0.38°, and 0.49° for concentrations of 6.0 × 108 CFU/mL, 6.0 × 107 CFU/mL and 6.0 × 106 CFU/mL respectively. However, the minimum reflectance rose from 0.09° to 0.14°, 0.20°, and 0.22°. Moreover, SPR testing with the structure of the prism/Au thin film/E. coli bacteria/air was carried out to determine the contribution of His-Ag NPs for detecting E. coli bacteria. The results showed that no angular shift occurs. These results indicate that using Ag NPs encapsulated with L-His is essential in amplifying the SPR signal and detecting E. coli bacteria. There was a notable alteration in both the LSPR angle and minimum reflectance indicating that adding His-Ag NPs facilitated the interaction between the E. coli and the sensor surface, thereby enhancing the performance of LSPR-based sensors for E. coli detection for low limit of detection value at 0.47 CFU/mL.

Comparison of Classification Data Mining C4.5 and Naïve Bayes Algorithms of EDM Dataset

The purpose of this research is to choose the best method by comparing two classification methods of data mining C4.5 and Naïve Bayes on Educational Data Mining, in which the data used is student graduation data consisting of 79 records. Both methods are tested for validation with 10-ford X Validation and perform a T-Test difference test to produce a table that contains the best method ranking. Different results were obtained for each method. Based on the results of these two methods, it is very influential on the dataset and the value of the area under curve in the Naïve Bayes method is better than the C4.5 method in various datasets. Comparison of the method with the 10-Ford X Validation test and the T-Test difference test is that the Naïve Bayes method is better than C4.5 with an average accuracy value of 73.41% and an under-curve area of 0.664.

Indonesian online newspaper reporting of suicidal behavior: Compliance with World Health Organization media guidelines

BACKGROUND

Despite the lack of attention, suicide is a major public and mental health problem in Indonesia. Research on how Indonesian newspapers portray suicide case has been lacking.

AIM

To assess the quality of Indonesian online newspaper reporting suicide news and its compliance with the World Health Organization (WHO) mass media reporting guidelines.

METHODS

The content of suicide news reported in online newspapers was searched and scrutinized against the WHO suicide reporting guidelines.

RESULTS

Within the duration of 6 months, there were 548 suicide news reported. This consisted of 16.8% attempted suicide and 83.2% completed suicide. Approximately 90.3% reported age, 97.3% reported gender and 64.3% reported the marital status of the victims. Furthermore, 68% reported the methods of suicide in headline or title, 40.5% shown the picture of the victims and 56.6% shown illustration only, and 67.2% reported life event related to suicide act.

CONCLUSION

The vast majority of online newspapers in Indonesia exaggerate suicide news. They rarely inform the readers that there is hope and help available. The majority also do not conform to the WHO media guidelines.

Erythropoietin protects the subventricular zone and inhibits reactive astrogliosis in kaolin-induced hydrocephalic rats

PURPOSE

To elucidate the potential role of erythropoietin (EPO) as a neuroprotective agent against reactive astrogliosis and reducing the thinning rate of subventricular zone (SVZ) in kaolin-induced hydrocephalic rats.

METHOD

Thirty-six ten-week-old Sprague-Dawley rats were used in this study. Hydrocephalus was induced with 20% kaolin suspension injected into the cistern of thirty rats and leaving the six rats as normal group. The hydrocephalic rats were randomly divided into hydrocephalic and treatment group. The treatment group received daily dose of recombinant human erythropoietin (rhEPO) from day 7 to day 21 after induction. The animals were sacrificed at 7 (only for hydrocephalic group) and 14 or 21 (for both groups) days after induction. Brain was removed and was prepared for histological analysis by hematoxylin and eosin staining as well as immunohistochemistry for 4-HNE, GFAP, Iba-1, and Ki-67.

RESULTS

Histopathological analysis showed that animals treated with rhEPO had a reduced astrocyte reactivity displayed by lower GFAP expression. Hydrocephalic rats received rhEPO also displayed reduced microglial activation shown by lower Iba-1 protein expression. Exogenous rhEPO exerted its protective action in reducing astrogliosis by inhibiting lipid peroxidation that was documented in this study as lower expression of 4-HNE than non-treated group. The SVZ thickness was progressively declining in hydrocephalus group, while the progression rate could be reduced by rhEPO.

CONCLUSION

Erythropoietin has a potential use for inhibiting lipid peroxidation, and reactive astrogliosis in hydrocephalic animal model. The reduced thinning rate of SVZ demonstrated that EPO also had effect in reducing the hydrocephalus progressivity. Further research is warranted to explore its efficacy and safety to use in clinical setting.

Frontoethmoidal encephalocele: clinical presentation, diagnosis, treatment, and complications in 400 cases

PURPOSE

The purpose of this study is to review a large series of frontoethmoidal encephalocele (FEE) regarding their clinical presentation, the progressiveness of the mass volume, the skin stigmata as well as its surgical approach and post-surgical complications.

METHOD

Records of all FEE patients treated in Soetomo General Hospital, Surabaya, and Charity Foundation Program from 2008 to 2015 were reviewed. Detailed patient's demography, clinical findings, radiology results, operative procedures, and complications were documented. Follow-up was organized in weekly basis for the first 1 month after surgery or more often when situation or complication occurred. Wound healing, neurological assessment for new or progressive deficit, pseudomeningocele, skin breakdown, cerebrospinal fluid (CSF) leakage, exposed implant, recurrent mass, and cosmetic results were documented. Since most of the patients had no direct phone line at their hometown, we relied on social worker to contact them.

RESULTS

One-stage surgery was performed for 400 patients with FEE (212 were male and 188 were female). Of 400 patients, 388 (97%) were younger than 18 years old. Most FEEs were nasoethmoidal, either isolated or combined with nasoorbital type (347 cases [86.75%]); nasofrontal subtypes were seen in 34 cases (8.5%) and nasoorbital in 14 cases (1.5%). The mean operative time was 2 h (range 30 min-3 h). There were only two patients (0.5%) needed postoperative blood transfusions. Mean hospitalization time was 5 days (range 4-7 days). Overall, complication rate in our series was 12.5%, mostly was CSF leakage and wound dehiscence.

CONCLUSION

The current socioeconomic conditions and local facility should be considered to treat these specific disease processes. The refined and meticulous technique, especially in choosing the approach and handling the dural closure, is essential in lowering the complication rate.

Development of pediatric neurosurgical service at Dr. Soetomo Hospital, Surabaya, Indonesia

PURPOSE

This review traces the history of pediatric neurosurgery at Dr. Soetomo General Hospital (DSGH) and its role in advancing the field of pediatric neurosurgery.

METHODS

The history, the founding fathers, and the next generations of the pediatric neurosurgery in DSGH were traced back from original sources and authors' life stories.

RESULT

Pediatric neurosurgical service at DSGH has its own unique perspective being a pediatric service in general hospital setting. It serves second largest city of Indonesia - the fifth most populated country in the world. Historical vignette and future perspectives are narratively presented.

CONCLUSION

As a pediatric neurosurgical service at general hospital in developing country, its development deserves a special mention.

Multiple spinal extradural arachnoid cysts occurring in a child

Symptomatic multiple extradural arachnoid cysts of the spine are extremely uncommon in children and have only rarely been reported. The authors report a case of multiple extradural spinal arachnoid cysts in a 14-year-old child who presented with signs of spinal cord compression. The disease affected the thoracic spine and extended from T-5 to T-10 with an underlying defect in the dura of the spinal canal that was predisposed to the formation of cysts. The authors describe the imaging examination, surgical planning, and surgical technique, and they review the literature. They also discuss the possible mechanisms of cyst formation.

Multiple spinal extradural arachnoid cysts occurring in a child

✓Symptomatic multiple extradural arachnoid cysts of the spine are extremely uncommon in children and have only rarely been reported. The authors report a case of multiple extradural spinal arachnoid cysts in a 14-year-old child who presented with signs of spinal cord compression. The disease affected the thoracic spine and extended from T-5 to T-10 with an underlying defect in the dura of the spinal canal that was predisposed to the formation of cysts. The authors describe the imaging examination, surgical planning, and surgical technique, and they review the literature. They also discuss the possible mechanisms of cyst formation.