SUMMARY TABLE OF RESEARCH PROPOSALS

Research Question / Topic Assessment
Can milk yoghurt containing Lactobacillus protect
mice against Salmonella enteritidis infection and
alter the immune response in mice? /
  • Literature search show evidence that Lactobacillus-containing probiotics have protective effects against Salmonella enteritides infection in mice through immune response modulation.
  • There is also a study that shows bactericidal effects of lactic acid producing bacteria condensate mixture in addition to the known inhibitory effect of this group of microorgansims on Salmonella enteritides.
  • Studies were already done regarding this topic.

Does Moringa oleifera extract prevent lipopolysaccharide/D-galactosamine induced acute liver injury in rats? /
  • From the literature (see below), they used extracts obtained from leaves. Maybe we can investigate and compare if the effects of MO extracts obtained from other parts of the plant (e.g. roots) have protective effects against drug or substance-induced liver injury.
  • In order to fit the study in a given time-frame (which is limited), we will focus on MO’s effects on acute liver damage.
  • MO is also readily available in the local setting, popular to the community and not difficult to acquire.
  • Lipopolysaccharide/D- galactosamine as agent for inducing acute liver damage was suggested since no studies used this yet.
  • Also, outcomes for this study only require blood samples in order to assess the effect on liver function.

How do PGH-OPD patients view dietary supplements as health products? / Topic Itself: can be narrowed to a certain category of dietary supplements (like pain relievers or anti-cholesterol supplements or osteoporosis-delaying supplements)
Medical Significance: significant enough because of 1) beneficial educational interventions for health professionals about these supplements and 2) patients’ skepticism on scientific findings, relying more on their trusted ones’ opinions
Feasibility: good location (only in PGH-OPD), good timeframe of implementation (days, not weeks), most of the time will be spent on preparing the questionnaire to ensure its information gathering capability and on data analysis, sample size may have to be very large to make it valid
Data Analysis: presentation using plots of percentages of patients, age, sex, information source, duration of usage, frequency of usage, reason for usage, disclosure rates, etc.
Disadvantage: low disclosure rates seeing that we are medical students; also sample size as mentioned
Does the purified extract of malunggay (Moringa oleifera) leaves have a bactericidal or bacteriostatic effect on common Gram positive (S. pyogenes, S. aureus) and Gram negative (E. coli, P. aeruginosa) bacterial cultures? / Topic Itself: can be narrowed to a certain part of the plant, and according to the literature search, the seeds exhibit the bactericidal effect; alternative topic could be water treatment
Medical Significance: significant enough because of 1) common illnesses caused by the bacterial strains proposed, 2) malunggay trees can be found locally and 3) can prove to be a low cost antibacterial substance; also 4) to partially test validity of dietary supplements from malunggay tree parts
Feasibility: will need a good seed source, moderate timeframe of implementation (about 2-3 weeks), time will be spent extracting from seeds, administration of treatment on cultures, and data analysis, good sample size (small) but needs many replications
Data Analysis: presentation using plots comparing antimicrobial activity of M. oleifera extract and broad spectrum antibiotic for the 4 proposed bacterial strains
Disadvantage: “simple” and common study, may come under heavy skepticism and criticism
Does Hibiscus rosa sinensis prevent inflammation more effectively than Carica papaya? / Topic Itself: Comparison of the anti-inflammatory properties of the two plants.
Hibiscus and Carica papaya have both been used as anti-inflammatory agents and several studies have shown their efficiency as anti-inflammatory agents. A comparison of the two, however, has never been made.
Medical Significance: Newer and more potentAnti-inflammatory agents are always needed. Given that both plants are locally available, one of these two plants could be a cheaper alternative to other anti-inflammatory drugs.
Feasibility: same as the proposal on Malunggay (Moringa oleifera). Another issue would be the feasibility of inducing inflammation in the test subjects (Sprague-dawley rats)
Data Analysis: Lymphocyte proliferation assays and complement-mediated hemolytic assay
Anti-microbial property of dayap (Limonia aurantifolia), duhat (Syzygium cumini), yakon (Smallanthus sonchifolius), bayabas (Psidium guajava), calamansi (Citrus microcarpa), and 10 other Philippine herbs/fruits. / Topic Itself: Either we can work on exploring Syzygium jamulanum’s diminished systemic inflammatory response or we can instead use other plants that have established microbicidal effect that is comparable to S. jambulanum and then do the same protocol. A synergism study can also be done on S. jambulanum since the plant extracts of S. aromaticum was found to have increased efficiency when used synergistically with antimicrobial drugs.
The leaf essential oils of Syzygium cumini and Syzygium travancoricum were tested for their antibacterial property. The activity of S. cumini essential oil was found to be good, while that of S. travancoricum was moderate.
Another study by Khan et al 2009 concludes that A. nilotica, C. zeylanicum and Syzygium aromaticum can be used against multidrug resistant (MDR) microbes causing nosocomial and community acquired infections.
The bactericidal activity of Syzygium jambulanum has also already been established in vitro. Thus research in this topic now includes its effects in the clinical setting. One example is a study by Maciel et al (2008) in which they studied its prophylactic anti-septic effect in mice (specifically, polymicrobial infection induced by cecal ligation and puncture). They got positive results, but the amazing thing about it is that they concluded that its anti-septic effect is not associated to the plant’s direct microbicidal effect but it is associated to a recruitment of activated neutrophils to the infectious site and to a diminished systemic inflammatory response.
Medical Significance: Significant enough considering that there’s always a need for newer and stronger anti-microbials due to the increasing number of resistant bacterial strains. In addition, newer, safer and cheaper anti-inflammatories are always needed.
Feasibility: Considering that the extraction of compounds is a tedious process, our study should be limited to just one or two plants listed above. The availability, extraction and procurement process of these plants should also be considered. Same issues with the malunggay (Moringa oleifera) leaves
Data Analysis: Presentation using plots comparing antimicrobial activity of the selected plant extracts and broad spectrum antibiotic for the multi-drug resistant microbes.
Do the aqueous and ethanolic extracts of Balitbitan (Cynometra ramiflora) exhibit anti-herpetic effects on cell cultures of Herpes Simplex Virus Type 1? / Topic: There’s this article showing that Cynometra ramiflora is cytotoxic, though it’s efficiency as an antiviral against herpes is not clear. But then again, we’ll be utilizing viral cultures of Herpes simplex and not cancer cell lines so the target population for our study will be different.
Medical significance: Significant because it’s a potential pharmacologic treatment for STDs.
Feasibility: Possible, given that we can get methanolic and aqueous extracts of Balitbitan. Aside from Balitbitan, the local name of Cynometra ramiflora is Oringen. This plant can be found in forests along streams located in Cagayan, Bulacan, Rizal, and Quezon. The procurement process for the leaves of the specific plant is still unknown, however and a botanist is needed to identify or certify the plant. By the way, the same article states that the leaves of Oringen are really used as an antiherpetic.
Data Analysis: The extracts can be examined for their antiviral activities against herpes simplex virus type 1 (HSV-1) by plaque reduction assay in vitro
Are the flavonoids (jaceosidin and eupatilin) extracted from Damong Maria (Artemisia vulgaris) cytotoxic to HPV positive cervical cancer cell lines? / Topic: A local study has already proven that Damong maria has cytotoxic effects on leukemic cells. I’m not so sure, but I guess we can change the population again to cervical cancer cell lines. And we’ll have to test a wider range of concentrations, so we can imitate the effect of chemotherapy drugs. Aside from that, may recommendation na we can look for other solvents na polar and non-toxic.
Another study showed another active ingredient (aside from the flavonoids) from the plant extract and that it can inhibit certain types of viruses. We can test if artenusate is an effective inhibitor of HPV.
The last study showed that Artemisia has antiviral activity (although against Herpes pa rin ang nakalagay). But in the study, another species was used.
Medical Significance:
Potential pharmacologic treatment against HPV (and possibly other cancer cells).
Feasibility: Feasible. Use of extracts and assays again. Main issue is, again, the procurement of the plant specimen and its certification. Also, the procurement of HPV positive cervical cancer cell lines might also be an issue.
Data Analysis: Analysis of the following parameters - cell growth, cell-cycle kinetics, apoptosis induction, and DNA synthesis
Can recombinant human erythropoietin improve healing of ischemic skin wounds in Sprague Dawley rats? / Topic Itself: not original topic, may have to add something to make it more innovative
Medical Significance: significant enough because of 1) search for substances to speed up wound healing and 2) will greatly help any tertiary hospital like PGH
Feasibility: moderate timeframe (about 1-2 weeks treatment, 1 week measurement and analysis), must also have skills required in inducing wounds and administering treatment
Data Analysis: histopathology analysis of collagen, measured variables are straightforward and objective measurements
Disadvantages: getting EPO may be expensive, as well as assays for growth factors; skills training in personnel as mentioned above
Do Lankauas have Anti-fungal and anti-microbial properties? / Topic itself: Will be first to report the said potential properties
Medical Significance: Can be expanded by possibly including other medically-important properties including dermatological conditions as used in folk medicine (tinea corporis), Comparison with luya-luyahan
Feasibility: Plants abundant
Data Analysis:May be able to get consultants from BIOTECH-UPLB and Bureau of Plant Industry
Disadvantages: Dilemma: Curcuma zedoria (another member of Zingiberaceae) is more popular; must make sure specimen collected is Langkauas and not Curcuma
Can purified malunggay (Moringa oleifera) root aqueous extract prevent or reduce induced acutely inflammation in Sprague Dawley rats? /
  • Moringa oleifera possesses promising antiarthritic property
  • M. oleifera was/is used to control activated mast cells so further studies would be more for elucidating MOA
  • Used hot water infusions of flowers, leaves, roots, seeds and stalks or bark
  • Serum level estimation of Rheumatoid Factor (RF) value and levels of selected cytokines (TNFalpha, IL-1, and IL-6)
  • Also checked ESR via whole blood
  • Liver homogenate for assessment of oxidative stress
  • Histopathology to measure degree of inflammation in synovial joint

Is Topical Epicatechin Effective as an Alternative Treatment to Ischemic Wound Healing? /
  • Topic itself: Has a parallel study using intradermal epicatechin on incision wounds instead
  • Medical Significance: alternative treatment to ischemic wound healing
  • Feasibility: Abundant in cocoa (available locally), pure form might be available, methods feasible
  • Data Analysis: Single-pedicle dorsal skin flap
  • Disadvantages: Epicatechin widely studied, varied only in type of wound (excision, incision, ischemia, thrombosis, etc.), source of epicatechin (pomegranate peel, epicatechin gallate, cocoa, etc.), and object of experiment (Wistar rats, Sprague-dawley rats, human cells, etc.). And besides, if the same experiment was already done in human cells (as found out in Search #1), would it still be significant to do its study on rats?

RESEARCH PROPOSAL LITERATURE SEARCH DETAILS

Suggested Topic: Protective effects of Milk Yogurt with Lactobacillus against Salmonella enteritides infection in mice

The studies below retrieved from literature search show evidence that Lactobacillus-containing probiotics have protective effects against Salmonella enteritides infection in mice through immune response modulation. There is also a study that shows bacteriocidal effects of lactic acid producing bacteria condensate mixture in addition to the known inhibitory effect of this group of microorgansims on Salmonella enteritides. Studies were already done regarding this topic.

Relevant Literature

Probiotic dahi (curd) containing Lactobacillus casei protects against Salmonella enteritidis infection and modulates immune response in mice.

Jain S, Yadav H, Sinha PR.

National Dairy Research Institute, Karnal, Haryana, India.

In the present study, effect of dahi containing probiotic Lactobacillus casei (probiotic dahi) was evaluated to modulate immune response against Salmonella enteritidis infection in mice. Animals were fed with milk products along with standard diet for 2 and 7 days prior to the S. enteritidis challenge and continued on the respective dairy food-supplemented diets during the postchallenge period. Translocation of S. enteritidis in spleen and liver, beta-galactosidase and beta-glucuronidase enzymatic activities and secretory IgA (sIgA) in intestinal fluid, lymphocyte proliferation, and cytokine (interleukin [IL]-2, IL-4, IL-6, and interferon-gamma [IFN-gamma]) production in cultured splenocytes were assessed on day 2, 5, and 8 of the postchallenge period. Colonization of S. enteritidis in liver and spleen was remarkably low in probiotic dahi-fed mice than mice fed milk and control dahi. The beta-galactosidase and beta-glucuronidase activities in intestinal fluid collected from mice prefed for 7 days with probiotic dahi were significantly lower at day 5 and 8 postchallenge than in mice fed milk and control dahi. Levels of sIgA and lymphocyte proliferation rate were also significantly increased in probiotic dahi-fed mice compared with the other groups. Production of IL-2, IL-6, and IFN-gamma increased, whereas IL-4 decreased in splenic lymphocytes collected from probiotic dahi-fed mice. Data showed that dahi prefed for 7 days before S. enteritidis challenge was more effective than when mice were prefed for 2 days with dahi. Moreover, probiotic dahi was more efficacious in protecting against S. enteritidis infection by enhancing innate and adaptive immunity than fermented milk and normal dahi. Results of the present study suggest that prefeeding of probiotic dahi may strengthen the consumer's immune system and may protect infectious agents like S. enteritidis.

Dahi containing probiotic Lactobacillus acidophilus and Lactobacillus casei has a protective effect against Salmonella enteritidis infection in mice.

Jain S, Yadav H, Sinha PR, Naito Y, Marotta F.

Animal Biochemistry Division, National Dairy Research Institute, Haryana, India.

Salmonella enteritidis infection has received attention during recent years owing to its high prevalence worldwide. In the present study, the protective effect of probiotic dahi (curd) supplemented with Lactobacillus acidophilus and L. casei against Salmonella enteritidis infection in mice is investigated. Seven days pre-feeding with probiotic dahi significantly increased anti-S. enteritidis sIgA (secretary IgA) antibodies and lymphocyte proliferation in S. enteritidis infected mice. IL-2, IL-6 and IFN-gamma production were significantly increased in supernatant of cultured splenocytes collected from mice pre-fed with probiotic dahi, while IL-4 levels were not changed significantly. Moreover, activities of beta-galactosidase and beta-glucuronidase, and counts of S. enteritidis in intestine, liver and spleen were decreased, whereas total lactobacilli in faeces were increased in mice pre-fed with probiotic dahi. Pre-feeding of probiotic dahi for 7 days was more effective than 2 days pre-feeding. Thus, the results indicate that, pre-feeding with probiotic dahi ameliorated S. enteritidis infection by stimulating specific and non-specific immune response. Above all, it lowered colonization of gastrointestinal tract as well as translocation of S. enteritidis.

Antimicrobial effect of lactic acid producing bacteria culture condensate mixture (LCCM) against Salmonella enteritidis.

Park JH, Seok SH, Cho SA, Baek MW, Lee HY, Kim DJ, Chung MJ, Kim SD, Hong UP, Park JH.

Department of Laboratory Animal Medicine, College of Veterinary Medicine and School of Agricultural Biotechnology, Seoul National University, San 56-1, Shillim-Dong, Kwanak-Gu, Seoul 151-742, Korea.

The antimicrobial effects of a lactic acid producing bacteria culture condensate mixture (LCCM) were assessed against Salmonella enteritidis. In the presence of LCCM, bacterial growth was assessed in vitro by the measurement of optical density (OD) and viable bacterial counting. At concentrations of 1.25 and 2.5% LCCM, OD values were significantly lower than that of the control broth, and at concentrations of 5 and 10% LCCM, OD values did not increase for the entire period of experiment. At 8 h after incubation, the viable bacterial numbers in 5% and 10% LCCM-containing broths were remarkably lower than that in the control broth. This antimicrobial ability of the LCCM was fundamentally attributed to causing cell death rather than inhibiting growth. Even when the pH of LCCM-containing broth was adjusted to 7.2, the number of viable bacteria was significantly lower in the broths containing LCCM over 2.5% than that in control broth at 8 h after incubation. However, the OD value of each culture in the presence of each concentration of the LCCM increased over 1.0 at the completion of the experiment. The in vivo antimicrobial effects of the LCCM against S. enteritidis were also assessed. In S. enteritidis-infected mice, the LCCM decreased both the viable bacteria found in the feces and the mortality rate of the mice. These findings showed that the LCCM might have an antimicrobial ability against S. enteritidis.

Suggested topic: Protective effects of Moringa oleifera root extract on lipopolysaccharide/D-galactosamine induced acute liver injury in rats.

Studies have shown that Moringa oleifera extracts have hepatoprotective effects in rats against drug-induced acute liver damage as evidenced by reduced serum markers (ALT, AST levels) of liver damage. The mechanism of action is on the enhancement of antioxidant activity and maintenance of antioxidant levels. From the literature (see below), they used extracts obtained from leaves. Maybe we can investigate or compare the effects of MO extracts obtained from other parts of the plant (e.g. roots) with MO extracts from leaves or if extracts from roots have protective effects against drug or substance-induced liver injury. In order to fit the study in a given time-frame (which is limited), we will focus on MO’s effects on acute liver damage. MO is also readily available in the local setting, popular to the community and not difficult to acquire. Lipopolysaccharide/D- galactosamine as agent for inducing acute liver damage was suggested since no studies used this yet. Also, outcomes for this study only require blood samples in order to assess the effect on liver function.