Effect of altitude and solvent on Psidium guajava Linn. leaves extracts: phytochemical analysis, antioxidant, cytotoxicity and antimicrobial activity against food spoilage microbes

BACKGROUND

Guava (Psidium guajava Linn.) has been traditionally used in the treatment of a wide range of diseases due to its rich content of secondary metabolites.

AIM

This study was aimed to evaluate the effect of altitude and solvent systems on guava leaves crude extract's phenolics and flavonoid content, antioxidant, antimicrobial, and toxicity nature.

METHODS

Guava leaves were collected from three different geographical locations in Nepal while solvents with an increasing polarity index were used for extraction. The yield percentage of extracts was calculated. Total Phenolic Content, Total Flavonoid Content, and antioxidant activity were determined by the Folin-Ciocalteu method, Aluminium chloride colorimetric method, and DPPH (2,2'-Diphenyl-1-picrylhydrazyl) assay respectively. The quantification of fisetin and quercetin was performed using the HPLC with method validation. The antimicrobial activity of the extracts was tested against bacteria and fungus isolated from spoiled fruits and vegetables and identified through 16s and 18s rRNA sequencing. Finally, Brine Shrimp Lethality Assay (BSLA) was used for testing the toxicity of the extracts.

RESULTS

The phenolic and total flavonoid content was found to be higher in ethanol extract (331.84 mg GAE/g dry extract) and methanol extract (95.53 mg QE/g dry extract) from Kuleshwor respectively. Water extract of guava leaves from Kuleshwor (WGK) did not show significantly different antioxidant activity when compared to methanol and ethanol extracts. Fisetin and quercetin were higher in WGK (1.176 mg/100 g) and (10.967 mg/100 g) dry extract weight respectively. Antibacterial activity against food spoilage bacteria was dose-dependent and found to be highest for all the extracts from different solvents and altitudes at higher concentrations (80 mg/ml). Similarly, methanol and ethanol guava extracts from all locations showed antifungal activity against Geotrichum candidum RIBB-SCM43 and Geotrichum candidum RIBB-SCM44. WGK was found to be non-toxic.

CONCLUSION

Our study concludes that the antioxidant and antimicrobial activity of WGK was found to be similar statistically to that of methanol and ethanol extracts of Bishnupur Katti and Mahajidiya. These results suggest the possibility of using water as a sustainable solvent to extract natural antioxidant and antimicrobial compounds which can further be used as natural preservatives to extend the shelf life of fruits and vegetables.

Photochemical internalization in bladder cancer - development of an orthotopic in vivo model

The possibility of using photochemical internalization (PCI) to enhance the effects of the cytotoxic drug bleomycin is investigated, together with photophysical determination and outlines of a possible treatment for intravesical therapy of bladder cancer. In vitro experiments indicated that the employment of PCI technology using the novel photosensitizer TPCS_2a® can enhance the cytotoxic effect of bleomycin in bladder cancer cells. Furthermore, experiments in an orthotopic in vivo bladder cancer model show an effective reduction in both the necrotic area and the bladder weight after TPCS_2a based photodynamic therapy (PDT). The tumor selectivity and PDT effects may be sufficient to destroy tumors without damaging the detrusor muscle layer. Our results present a possible new treatment strategy for non-muscle invasive bladder cancer, with the intravesical instillation of the photosensitizer and bleomycin followed by illumination through an optic fiber by using a catheter.

Markers of Autolysis in Acute ST Elevation Myocardial Infarction

INTRODUCTION

The availability of reliable noninvasive markers for infarct-related artery (IRA) patency status are very limited, otherwise could allow early identification of patients with patent IRA, for whom repeat thrombolysis or rescue percutaneous coronary intervention (PCI) are not necessary.

METHODS

We conducted a single centered retrospective study of STEMI patients undergoing primary PCI to determine how various factors such as demographic characteristics, risk markers of coronary heart disease, clinical and blood parameters present differently in patients with higher coronary flow and patent infarct related artery from patients with total occlusion at the time of initial angiography and how they affect in outcome of the disease.

RESULTS

MPV level (11.96 fL vs. 10.92 fL, P < 0.001), Lp (a) level (179.57 nmol/l vs 141.16 nmol/l , p < 0.001), CK-MB (290.2 vs. 190.98, P < 0.001), total cholesterol level (4.11 mmol/L vs. 3.8 mmol/L, p < 0.02) in total occlusion group were higher than in the patent IRA group. Wall motion abnormality was 77.2% for 203 patients with total occlusion group and 54.2% for 83 patients with patent IRA group (P<0.01). Mean hospital stay days were higher in total occlusion group as compared to the patent IRA group P < 0.01.

CONCLUSIONS

MVP, Lp (a), TC, and CK-MB levels and myocardial wall motion at the presentation may play the role of markers for IRA patency status that will help in early identification of patients with IRA, for whom repeat thrombolysis or rescue PCI may not be required.

Obstetric Hysterectomy and Maternal Survival

Aims: This study was done to analyze the cases of obstetric hysterectomy and maternal complications and survival after that. Methods: A retrospective study was carried out from the review of records   of the near miss, maternal mortality, cesarean audit and operation theater record of the Department of Obstetrics and Gynaecology, Tribhuvan University Teaching Hospital (TUTH), Kathmandu from 2057-2071 BS. Results: Fourteen maternal survival resulted following total of 19 obstetric hysterectomy, subtotal hysterectomy being the procedure of choice in 11 cases, emergency peripartum hysterectomy (EPH) being performed in abundance (18/19) in comparison to an elective peripartum hysterectomy, which was undertaken in a single case of placenta percreta, and inclusive of latter were four cases of morbid placental adhesion, a placenta increta and two placenta accreta. Eight out of 19 cases had vaginal delivery and rest had cesarean section. Among seven cases of cesarean hysterectomy 3 were done for placenta previa with accreta one case each done for abruptio placentae  and placenta accreta and two cases were done for extra placental causes. Among four cases of emergency peripartum hysterectomy (EPH), which were relaparotomy followed by hysterectomy, three cases were done for complication of cesarean section and one done for uterine atonicity. Four cases of spontaneous vaginal deliveries needed peripartum hysterectomy two of them were complicated by morbid placental adhesion placenta increta (1), placental percreta (1), two cases were vaginal birth after cesarean (VBAC). Seven cases of uterine rupture had undergone peripartum hysterectomy.   Conclusions: Obstetric hysterectomy is a lifesaving surgical procedure for maternal survival whenever necessary and mandates a quick decision making process, however in consideration of younger age and low parity or nulliparity, the best obstetric governance and services must foresee not to let mothers meet such situation necessitating organ removal and to enjoy potential reproductive life cycle.DOI: http://dx.doi.org/10.3126/njog.v9i2.11759    

Semen Parameters of Fertile Men Attending Tribhuvan University Teaching Hospital

Aims:  This study was done to analyze the semen parameters of fertile Nepalese men with a known time to pregnancy of less than or equal to 12 months and to compare the values obtained with the newer reference limit of WHO, 2010.Methods: A hospital based prospective cross- sectional study was conducted at Tribhuvan University Teaching Hospital, Institute of Medicine, from 15th April 2012 – 15th April 2013. Sixty fertile men with a known time to pregnancy (TTP) ≤ 12 months were included in the study and semen collection and analysis done at the laboratory of Department of Pathology. Results: The following one-sided reference limits, the fifth centile (with 95th percent confidence interval), were generated: semen volume, 1.0 ml (0.8-1.2); total sperm number, 25 million per ejaculate (11-39); sperm concentration, 10 million per ml (5-15); progressive motility, 15% (10-20); total (progressive plus non-progressive motility) motility, 30% (25 -35); vitality 50% (46-54); morphologically normal form, 99% (99.3- 99.4). Conclusions: The study concluded that only a single semen parameter cannot be conclusive of fertility, therefore combination of all semen parameters is more predictive. In addition the study also concluded that the semen parameters of Nepalese fertile men were found lower as compared to reference limits of WHO. DOI: http://dx.doi.org/10.3126/njog.v9i2.11772

Managing Pregnancy with Post Mitral Valve Replacement Presenting Late

With the increased awareness and emphasis of institutional delivery, there has been an increase in trend of cases of valvular heart disease with pregnancy being reported to tertiary centers. Though rare, cases like post mitral valve replacement (MVR) with pregnancy are often a challenge in terms of management with an outcome of uneventful pregnancy and healthy baby. The management of women with prosthetic heart valves during pregnancy poses a particular challenge as there are no available controlled clinical trials to provide guidelines for effective antithrombotic therapy. Here we present a case of post MVR with pregnancy with an ultimate outcome of a healthy female and uneventful vaginal delivery. Nepal Journal of Obstetrics and Gynaecology / Vol 8 / No. 1 / Issue 15 / Jan- June, 2013 / 50-52 DOI: http://dx.doi.org/10.3126/njog.v8i1.8866

A randomized study comparing intravaginal prostaglandin (PGE2) with oxytocin for induction of labour in premature rupture of membrane at term

This is a prospective randomized study conducted in Tribhuvan University Teaching Hospital from February 2008 to January 2009. Total 72 women with Premature rupture of membranes (PROM) were included. Thirty-six women received PGE2 vaginal gel and thirty-six received iv oxytocin. Induction was successful in majority of cases in both the groups; 88.8% in PGE2 and 83.3% in oxytocin group (p value = 0.063). Time duration from induction to active stage was comparable (p value = 0.273). Induction to delivery interval was significantly low in oxytocin group (p value = 0.002) but leaking to delivery interval was similar in both the groups (p value = 0.083). PGE2 had slightly higher side effect than oxytocin. PGE2 and oxytocin were both effective and safe for induction of labour in women with PROM at term. There was no significant difference in maternal and fetal outcome, hospital stay, leaking to delivery interval, maternal and neonatal side effects, though induction to delivery interval was significantly less with oxytocin.

Comparative susceptibility of two banana cultivars to Banana bunchy top virus under laboratory and field environments

Field and laboratory experiments were carried out on the island of Oahu, HI, to compare the susceptibility of the two most commonly grown banana (Musa sp.) cultivars in the state ('Dwarf Brazilian' or Santa Catarina [locally known as dwarf apple] and 'Williams') to the aphid-borne Banana bunchy top virus (genus Babuvirus, family Nanoviridae, BBTV). Several morphological and physiological features of the two cultivars were monitored to determine whether the banana aphid, Pentalonia nigronervosa Coquerel (Hemiptera: Aphididae), transmits BBTV to both cultivars at a similar rate; and whether after successful inoculation, does each cultivar respond similarly to viral infection. Results from the laboratory experiment showed that a similar percentage of both cultivars were infected with BBTV by aphid vectors (> 90% for both cultivars). However, field results showed a significantly lower percentage of dwarf apple (39%) infected with BBTV compared with Williams (79%). We also found that all physiological and morphological features measured (i.e., plant height, leaf area, canopy, chlorophyll level, and moisture content) for both cultivars were impacted similarly by BBTV. The incubation period, or the time between plant infection and initial appearance of disease symptoms, was similar for both cultivars. Results also showed that BBTV transmission efficiency was lower in the field than in the laboratory, despite that more aphids per plant were used for field than laboratory inoculation tests. The results highlight the potential use of less susceptible cultivars to help manage BBTV and the importance of screening banana varieties in the field to determine their response to vectors and associated diseases.

The Development of New Skin Tests: A Tool for the Eradication of Leprosy

Abstract

High levels of inflammatory cytokines are associated with poor clinical response to steroid treatment and recurrent episodes of type 1 reactions in leprosy

Levels of leprosy antigen-induced interferon-gamma (IFN-gamma), tumour necrosis factor alpha (TNF-alpha) and interleukin-10 (IL-10) were measured in 96 leprosy patients with type 1 reactions (T1R) before, during and after a standard 12-week course of steroids. Peripheral blood mononuclear cells (PBMC) from leprosy patients with untreated T1R produced significantly more TNF-alpha than leprosy patients without T1R. Median levels of IFN-gamma and TNF-alpha in T1R patients fell during treatment with steroids; however, TNF-alpha levels increased as the steroid dose was reduced. Median IL-10 levels increased throughout the steroid treatment period and were associated strongly with TNF-alpha levels. Patients with high cytokine levels had a poorer recovery of sensory or voluntary muscle nerve function, a higher risk of reactivation of symptoms during steroid treatment, and a higher risk of another episode of T1R within 2 months of completing the steroid regimen. Rapid and effective reversal of the inflammatory process in T1R is critical to prevent permanent nerve damage from T1R and monitoring cytokine levels during treatment may be useful.

Application of constructed wetlands for wastewater treatment in Nepal

Surface water pollution is one of the serious environmental problems in urban centers in Nepal due to the discharge of untreated wastewater into the river-system, turning them into open sewers. Wastewater treatment plants are almost non-existent in the country except for a few in the Kathmandu Valley and even these are not functioning well. Successful implementation of a few constructed wetland systems within the past three years has attracted attention to this promising technology. A two-staged subsurface flow constructed wetland for hospital wastewater treatment and constructed wetlands for treatment of greywater and septage is now becoming a demonstration site of constructed wetland systems in Nepal. Beside these systems, five constructed wetlands have already been designed and some are under construction for the treatment of leachate and septage in Pokhara municipality, wastewater in Kathmandu University, two hospitals and a school. This paper discusses the present condition and treatment performance of constructed wetlands that are now in operation. Furthermore, the concept of the treatment wetlands under construction is also described here. With the present experience, several recommendations are pointed out for the promotion of this technology in the developing countries.

A postgenomic approach to identification of Mycobacterium leprae-specific peptides as T-cell reagents

To identify Mycobacterium leprae-specific human T-cell epitopes, which could be used to distinguish exposure to M. leprae from exposure to Mycobacterium tuberculosis or to environmental mycobacteria or from immune responses following Mycobacterium bovis BCG vaccination, 15-mer synthetic peptides were synthesized based on data from the M. leprae genome, each peptide containing three or more predicted HLA-DR binding motifs. Eighty-one peptides from 33 genes were tested for their ability to induce T-cell responses, using peripheral blood mononuclear cells (PBMC) from tuberculoid leprosy patients (n = 59) and healthy leprosy contacts (n = 53) from Brazil, Ethiopia, Nepal, and Pakistan and 20 United Kingdom blood bank donors. Gamma interferon (IFN-gamma) secretion proved more sensitive for detection of PBMC responses to peptides than did lymphocyte proliferation. Many of the peptides giving the strongest responses in leprosy donors compared to subjects from the United Kingdom, where leprosy is not endemic, have identical, or almost identical, sequences in M. leprae and M. tuberculosis and would not be suitable as diagnostic tools. Most of the peptides recognized by United Kingdom donors showed promiscuous recognition by subjects expressing differing HLA-DR types. The majority of the novel T-cell epitopes identified came from proteins not previously recognized as immune targets, many of which are cytosolic enzymes. Fifteen of the tested peptides had > or =5 of 15 amino acid mismatches between the equivalent M. leprae and M. tuberculosis sequences; of these, eight gave specificities of > or =90% (percentage of United Kingdom donors who were nonresponders for IFN-gamma secretion), with sensitivities (percentage of responders) ranging from 19 to 47% for tuberculoid leprosy patients and 21 to 64% for healthy leprosy contacts. A pool of such peptides, formulated as a skin test reagent, could be used to monitor exposure to leprosy or as an aid to early diagnosis.

Strong human immunodeficiency virus (HIV)-specific CD4+ T cell responses in a cohort of chronically infected patients are associated with interruptions in anti-HIV chemotherapy

Virus-specific CD4+ T-helper cell function is important in controlling human immunodeficiency virus (HIV) infection but is impaired in patients with progressive HIV disease. It has been reported that after highly active antiretroviral therapy (HAART), HIV-specific lymphoproliferative responses remain absent, whereas responses to non-HIV microbial antigens are restored. However, in analyzing immune responses in a cohort of chronically infected adults on HAART, we observed strong HIV-specific CD4+ T cell responses of Th-1 phenotype in 11 of 22 patients. The magnitude and frequency of HIV-specific lymphoproliferative responses was strongly associated with previous interruptions in HAART (P=.001). In contrast, the magnitude of CD8+ T cell responses to HIV Gag, Pol, Env, and Nef was similar in patients who had and those who had not interrupted HAART. We conclude that (1) a significant proportion of chronically HIV-infected patients on HAART can generate strong HIV-specific CD4+ and CD8+ T cell immunity and (2) transient interruptions in antiviral treatment may prime or boost HIV-specific CD4+ T-helper responses.

Interferon-gamma responses to candidate leprosy skin-test reagents detect exposure to leprosy in an endemic population

New tools for the detection of leprosy exposure in a community will be necessary for the eradication of leprosy. Candidate leprosy skin-test antigens derived from the fractionation of the leprosy bacillus into cytoplasmic and cell-wall proteins free of immuno-inhibitory mycobacterial lipoglycans and carbohydrates were used in an overnight blood test to determine whether exposure to leprosy can be detected by the production of the cytokine interferon gamma (IFN-gamma). Strong IFN-gamma responses were detected in leprosy contacts to both skin-test antigens compared with control subjects from the same endemic communities. There was little response in patients with tuberculosis. Responses were greatest in contacts with recent leprosy exposure. The implications of these findings for the application of these reagents in a field trial as skin tests to detect exposure to leprosy are discussed in light of the strong association between overnight IFN-gamma to PPD and the tuberculin skin-test responses previously reported.

Risk factors for erythema nodosum leprosum

A retrospective study of new borderline lepromatous and lepromatous patients reporting for multidrug therapy (MDT) for leprosy at the Anandaban Leprosy Hospital, Kathmandu, Nepal, over an 8-year period was conducted to determine the prevalence of erythema nodosum leprosum (ENL), the time and frequency of reactions, and clinical and laboratory parameters associated with ENL. An overall prevalence of ENL in this cohort of 19% was found. One third of these reactions occurred in patients before MDT was given, one third in the first 6 months and one third after 6 months of treatment. Nearly 1 in 10 of the ENL reactions occurred in patients who had completed 2 years of MDT; 45% of patients with ENL had more than one episode. Data collected at the patients' first presentation was used to identify four major risk factors. Patients with lepromatous disease, skin infiltration or a bacterial index (BI) of > 4+ were at significantly increased risk. Patients older than 40 were at significantly decreased risk of ENL. There was a linear relationship in the risk of ENL with an increasing BI and an inverse relationship to increasing age. These observations should enable clinicians to recognize patients at first presentation who will be likely to develop ENL.

Toxoplasma antibody prevalence in Nepalese pregnant women and women with bad obstetric history

Sera from randomly selected 345 pregnant Nepalese women aged 16-36 years and 13 women with bad obstetric history (BOH) were tested for the presence of Toxoplasma antibodies using microlatex agglutination (MLA) and ELISA methods. The overall prevalence was 55.4% (191/345). Prevalence was slightly higher (59.0%) in older age-group (27-36 years) compared with younger age-group (16-26 years) (52.2%). No significant difference in antibody prevalence in women belonging to two different ethnic-groups (Tibeto-Burmans 57.8%, Indo-Aryans 52.7%) was observed (p>0.05). MLA antibody titer ranged from 1:16 to 1:2,048. Over three-fourth of the women showed either high (1:510 or over) or low (1:16 or 1:32) antibody titer. Three percent (6/191) of MLA antibody positive subjects had Toxoplasma IgM antibodies by IgM-ELISA. All six IgM antibody positive pregnant women had MLA antibody titer of over 1:510. Of the total 13 women with BOH, 5 (38.5%) had Toxoplasma antibodies of which 2 (40.0%) were positive for Toxoplasma-IgM antibodies.

Isolation of verotoxigenic Escherichia coli from the Tasmanian environment

Growing concerns on the emergence of verotoxin producing Escherichia coli (VTEC) in Australia have focused our attention on the possible sources of VTEC within the island state of Tasmania. An analysis of 156 food samples and 194 water samples obtained from various areas revealed evidence of eight possible sources. Six strains, with serotypes Ont:Hnt, O86:H-, O88:H-, O126:H21 and O134:H-, were isolated from water samples. Two VTEC of serotypes Ont:H8, 081:H- were isolated from raw meat samples. The waterborne isolates produced verocytotoxin. VT1, while both foodborne isolates were strong producers of VT2. Three VTEC isolates produced haemolysins, only one produced enterohaemolysin (EntHly) and the remaining were reported with alpha-haemolysin (alpha-Hly) activity. An important feature in the majority of isolates from water was their lack of ability to ferment lactose these isolates are routinely overlooked in public health laboratories.

Chorioangioma of Placenta

We report a case of Chrioangima of placenta resulting to hydropsfetalis. A 24 yrs old primigravida with polyhydramnios and large placental chorioangioma at 24 wks of gestation expelled a nonimmune hydropic male baby weighing 900gms. The baby expired after 5 minutes of expulsion. Keywords: Placental chorioangioma; Hydropsfetalis; Polyhydraamnios DOI: http://dx.doi.org/10.3126/mjsbh.v9i2.5026 Medical Journal of Shree Birendra Hospital Vol.9(2) 2010: 44-46