Following hematopoietic stem cell transplantation (HSCT), the Coagulase- negative Staphylococci (CoNS), has been found to cause a nosocomial Staphylococcus epidemic disease named sequence type ST27 or ST2 (55). Biofilm formation on medical tools is said to be the most significant S. epidermis virulence factor. The biofilm results from poly-N-acetyl glucosamine (PIA/PNAG) and other enzymes encoded by ica ADBC operon found in S. epidermidis ST27/ST2 strains.
A study carried on a leukemic patient illustrates the S. epidermis case of infection. This patient had acquired HSCT that was allogeneic from a relative donor. Secondly, the study illustrates the existing link between the clone of S. epidermidis ST27/ST2 and the strain. In addition, the difference that exists in the development of biofilm and the resistance of oxacillin in the time of infection is examined.
A 23-year old man leukemic patient, revealed how allogeneic HSCT cord blood stem cells were employed to heal a patient that had an acute type B- cell lymphoblastic leukemia (55). The patient had a fever soon after transplantation and was treated with a Vancomycin dosage. tibial muscles of the patient were found to be soft and red. Following this, blood cultures that tested positive for S. epidermidis were studied over a 6-week period (Table 1) (isolates 1-8).
An MRI (Magnetic resonance imaging) carried out on the patient illustrated a high intensity aplasia and a collection of liquid that had traces of musculus in extensor hallucis and tibial muscles. Groups of necrotic coccoid bacteria were discovered in histological results of both tibial muscles as identified in isolate 9 and 10 (Table1).
After the treatment, the patient experienced stiffness in the nuchal and experienced headache. An MRI revealed the patient’s brain had two lesions with septic emboli while the cerebrospinal fluid contained S. epidermidis isolates11 and 12 (Table 1). Despite the blood cultures indicating negative results daily, the patient remained febrile after transplantation with haplo-identical cells from the mother. Soon after, the patient died after developing an acute respiratory disease (ARDS) with multi-organ failure that progressed rapidly.
Various methods and materials were utilized to study strain description and development by growing the strains on agar. The colonies were then studied using Polymerase Chain Reaction to identify operon icaC and icaA. Biofilm development was studied using S.carnosus and S .epidermidis as negative and positive controls respectively. To treat the biofilms, protease K and sodium periodate were employed. During an examination of the negative variants of biofilm formation, black and red colonies on Congo red agar (CRA) were discovered. The total numbers of CFU from the black and red colonies were calculated. A gel ran through pulse-field electrophoresis was carried out. Through this method, Staphylococcal cassette chromosome typing was done. The PCR technique also helped identify mecA. Southern hybridization traced the IS256 strain copies. By use of restriction enzymes, EcoRI, the DNA was digested to generate probes used in the study.
The results found out that CSF samples and blood primary cultures produced colonies that had a different color and size. These colonies revealed S. epidermis by employing rRNA sequencing. The resistance to oxacillin, mediated by a gene known as mecA, was detected by PCR. Oxacillin resistance was susceptible during the 13-40 days (Table1). Isolates sampled by the 52nd and 55th day were all resistant and a SCCmec typing was able to detect a type VI cassette which lacked in the variants that were oxacillin sensitive (Table1) (55). The presence of mecA gene was associated with the power that the isolates had in producing biofilm in vitro. This was linked with the presence of a gene called ica (Fig. 1A and Table 1). From 13 to 40 days, isolates of ica-positive produced small amounts of biofilms that were mediated by weak proteins but by the 52nd to 55th day, production of PIA made the biofilms stout. (Fig.1A). Ica-positive isolates portrayed five specific strips of IS256 on Southern hybridization. In variants that were ica-negative, four bands were revealed. This added in the development of biofilm (Fig. 1C).
Results analysis indicated two strains of S. epiderdimis were responsible for the infection. An analysis of PFGE revealed similar patterns of restriction that referred to an isolate of the clonal origin. However, variants of mecA and ica negative lacked a DNA fragment that is 100-kb (Fig. 1B). An arc gene was absent in the MLST scheme. From the Congo red agar, the Mec A and ica negative isolates could be developed from a positive genotype of ica.(Table 1). This was demonstrated by presence of red colonies at frequency of 10 -2 per cell and generation.
epidermis has made it difficult to make a conclusion whether there is a certain type of isolate that is responsible for the disease or shows a contamination that is uncommon. In the primary cultures, the contamination in the leukemic patient was depicted from the growth of colonies (55). In addition, a common type clonal origin was discovered through molecular typing. The ST27/ST2 strains were depicted as S. epidermidis. This is now depicted in medical services as an epidemic pathogen. The ica operons give the strains the ability to create biofilms. The development of biofilm and genetic flexibility is significant. This is because they are employed by the S. epidermis for survival against the patient’s response to immunity and medication.
Ica-positive isolate causes biofilms that are protein mediated instead of PIA mediated at the beginning of the infection. However, those isolates contain icaADBC operon (Fig. 1A). The absent PIA creation’s molecular basis may be linked to various types of metabolic management (55). The surrounding conditions may be responsible for producing PIA. This may be associated by various types of metabolic.
In conclusion, the report confirmed that certain types of S. epidermidis strains might bring danger to susceptible patients. This is especially with patients who are immunocompromised. This indicates a significant role for the development of biofilm in disease persistence.
This study was meant to investigate the biofilm hypervariability formation and the resistance of oxacillin to S. epidermidis. It will illustrate the link between the epidemic ST27/ST2 strains. It was presented with a specific aim to address the current need of the medical microbiology and the cost effectiveness of biofilm formation. This also deals with the oxacillin resistance with the S. epidermidis. This is important both in the field of science and medical microbiology.
Formation of the ST27 and ST2 as isolates with biofilm capacity post a problem, which is requires precise treatment. This study exhibits high validity based on the materials, methods and tools of analysis used. For instance, the use of ST2 instead of ST27 has been supported by recent studies (8, 12, and 16). Similarly, the use of ST27 and ST2 in referring to the CoNS improves clarity and acceptability based on pre- and post-revised MLST schemes (12, 17).
It would be easier to read and comprehend the article if appropriate headings were made, especially in the methodology where materials and the methods are mixed.
From the abstract, the study goals, methods and deductions are made. The use of scientific terms such as ‘aplasia’ need to be explained for one to decode their meaning. Use of complex phrases such as ‘biofilm mediating ice locus and ‘oxacillin resistance conferring mecA gene’ require to be introduced in such a way as to easily relate to the topic without confusing the reader.
The introduction is short and unable to provide basic background regarding the work. Nosocomial nature of the ST27/ST2 was not fully demonstrated as a review. The degree of pathogenesis and the mode of biofilm production were not justified in the study. The article could be improved by incorporation of reviews about MLST, stereotyping of ST27/ST2, biofilm production and mode of pathogenicity of ST27/ST2. An overview on the state of bacterial genetic variability should be incorporated. Hypothesis and objectives of the study was lacking. The introduction should be more elaborative and compressive to give a detailed and scientific idea about the work. This will also help in drawing a conclusion out of the work.
Portions of the paper seem to be very long such as the materials and method section. The title is very long and a bit confusing. Focus of the study includes several fields of study as to hypervariability, resistance and threats caused by the microorganism (4, 10, 13). The methodology followed was relevant but lacked a detailed protocol. It should be more elaborative in terms of the methods followed during the study. Details of MLST, multiplex PCR strategy and SCCmec typing should be incorporated. The total CFU and associated frequency calculation lack references and it should be indicated.
The discussion section, covers the results well on the S. epiderdermis and an effort was made to link the results with literature. The basis of formation and role of biofilm in pathogenesis of the strain was addressed. Factors regulating PlA mediated biofilm formation were the central point of discussion, however, the major pit falls were the non identification of key molecular mechanisms associated with generation of genetic mimicry in the strains; why the strain were at the early part of infection, both oxacillin resistant and sensitive and in later stages became oxacillin resistant as well the molecular basis behind PlA and protein mediated biofilm formation.
The use of color description was not evident as there was absence of actual colors in the diagrams and pictures.
The table presented is too congested and the form of SCCmec was not clear, as there is no distinction done on the type IV entries in the table.
Figures are also not pleasing as they were clumped together without the proper heading or title for each. The title appeared on the following page mistakenly as a footnote.
Figure A which shows the absorbance results was supported by legends, but the plates were not clearly identified with results or color differentiation.
Figure B is the results given by the PFGE test where the isolates were presented with bands. Arrows were used in the presentation but is unclear as to what should be seen as a differentiation between isolates and between bands.
Figure C is a simple representation of the isolates gathered from the immunocompromised patient and that no inference can be made as a visual comparison was lacking.
It would be best if the label was placed immediately after the figures as this will help the reader to analyse the data presented. Most results were interpreted with explanation, and that there is a future suggestion for improvement. In the discussion, it was said that this approach is the current option for majority of oncologists in eradicating residual diseases (5. 7), National Cancer Institute (11) does not recognize its effectiveness especially in relapse cases of cancer as the one presented in this article. Based on this fact, the best treatment could have been salvage and consolidation therapies (12) in which cytarabine combined with anthracyclines or antimetabolites is used to eliminate the residuals of S. epidermidis that could not be detected in the previous visits (5, 9).
Regarding the specificity of the study, the media used and the method performed was well done and had the ability to support the growth of the S. epidermidis. There was the use of the sample isolates from the actual patient and control groups. The PFGE and the Congo red played a vital role in the identification and results of the test to come up with the right interpretation of the outcome of the study.
The conclusion was incorporated in the discussion as there were neither headings found in the article nor a recommendation sub heading.
The referencing and citation done was turabian which is the proper academic citation used in a scientific and technical writing. Though, inconsistency in the entries of the actual use of material is noticeable with the oldest reference being 1989 and the latest, 2008. With the above observations, this study should be given some modifications to address those inconsistencies. This will make the survey more strength.
Our Service Charter
Excellent Quality / 100% Plagiarism-FreeWe employ a number of measures to ensure top quality essays. The papers go through a system of quality control prior to delivery. We run plagiarism checks on each paper to ensure that they will be 100% plagiarism-free. So, only clean copies hit customers’ emails. We also never resell the papers completed by our writers. So, once it is checked using a plagiarism checker, the paper will be unique. Speaking of the academic writing standards, we will stick to the assignment brief given by the customer and assign the perfect writer. By saying “the perfect writer” we mean the one having an academic degree in the customer’s study field and positive feedback from other customers.
Free RevisionsWe keep the quality bar of all papers high. But in case you need some extra brilliance to the paper, here’s what to do. First of all, you can choose a top writer. It means that we will assign an expert with a degree in your subject. And secondly, you can rely on our editing services. Our editors will revise your papers, checking whether or not they comply with high standards of academic writing. In addition, editing entails adjusting content if it’s off the topic, adding more sources, refining the language style, and making sure the referencing style is followed.
Confidentiality / 100% No DisclosureWe make sure that clients’ personal data remains confidential and is not exploited for any purposes beyond those related to our services. We only ask you to provide us with the information that is required to produce the paper according to your writing needs. Please note that the payment info is protected as well. Feel free to refer to the support team for more information about our payment methods. The fact that you used our service is kept secret due to the advanced security standards. So, you can be sure that no one will find out that you got a paper from our writing service.
Money Back GuaranteeIf the writer doesn’t address all the questions on your assignment brief or the delivered paper appears to be off the topic, you can ask for a refund. Or, if it is applicable, you can opt in for free revision within 14-30 days, depending on your paper’s length. The revision or refund request should be sent within 14 days after delivery. The customer gets 100% money-back in case they haven't downloaded the paper. All approved refunds will be returned to the customer’s credit card or Bonus Balance in a form of store credit. Take a note that we will send an extra compensation if the customers goes with a store credit.
24/7 Customer SupportWe have a support team working 24/7 ready to give your issue concerning the order their immediate attention. If you have any questions about the ordering process, communication with the writer, payment options, feel free to join live chat. Be sure to get a fast response. They can also give you the exact price quote, taking into account the timing, desired academic level of the paper, and the number of pages.