in vitro culture and isoenzyme analysis of giardia lamblia

More documents

Recommendations

Info

countries with peak infections in late summer/early autumn (Flanagan, 1992; Hall, 1994). In the present study, such a pattern of transmission could not be established from the samples submitted to KEH Micribiology laboratory. This group comprised of a mixture of outpatient and hospitalised subjects coming from different geographical areas. Owing to (1) sample bias (2) the periodic deworming and irregular collection periods from day care centres and institutions, conclusions regarding seasonal trends could not be drawn for this population subset. However, data from this study indicate that the prevalence of Giardia in childcare centres ranged between 12,5% and 75% at anyone-collection time. Among the faecal specimens submitted to the laboratory and KEH hospitalised patients, the number of positive samples ranged between 0,36 and 23,5%. Predominantly higher infection rates occurred in children aged 2-5 years. This is consistent with the reported peak prevalence at this age interval (Sullivan et al. 1991; Hall, 1994). However, the values obtained in this study are most probably an underestimation of the true prevalence of this organism in the local setting for two reasons: • In most cases, single stool examinations were undertaken. It has been shown that single stool examinations will miss many pathogenic protozoan infections. Hiatt et al. (1995), compared the sensitivity of one stool examination with that of three examinations and found that with the additional examinations, the yield increased by 22,7% for E.histolytica, 11,3% for G.lamblia and 31,1 % for D.fragi/is • Second1y, the low sensitivity of stool microscopy for Giardia results in high rates of false negatives in their detection (Ament & Rubin, 1972; Kamath & Murugasu, 1974). • All the samples retrieved from the KEH laboratory were screened by direct 61
examination of wet preparations. This method is documented to be far less sensitive than using a concentration method to enhance detection of cysts (Ritchie, 1948). Nonetheless, these data reflect a high prevalence of Giardia among institutionalised, young subjects. In the one institution where repeated stool collections were made, the same children were consistently found to be excreting cysts at different collection times (time intervals in between collections varied between two weeks to three months). It is not clear whether these were repeated reinfections or persistence of the same infections because at Othandweni Home, regular mass treatments with Mebendazole were undertaken by a clinician attached to the MRC Amoebiasis Research Unit during the study period. (Previous experience with a treatment regimen comprising of Mebendazole and Metronidazole could not eradicate Giardia infections at this Home (Jackson TFHG, personal communication). Finally, institutionalised individuals, particularly preschool children, proved to be a reliable source of Giardia cysts. Work requiring a constant supply of fresh cysts, should be based in such a setting. Early investigators speculated on probable symbiont existence between Giardia and yeasts in the small intestine (Karapetyan, 1962; Meyer, 1979). Association of Giardia with yeasts was found in 25% of stools from the hospital subjects and was not prominent in stools obtained from the day-care subjects (4,5%). It would appear from this observation that antibiotic-induced disruption of the gut microbial flora (in the hospitalised individuals who in all likelihood were on antimicrobial therapy) resulted in the preponderance of opportunistic yeasts. 62
Page 1 and 2:
IN VITRO CULTURE AND ISOENZYME ANAL
Page 3 and 4:
(j)edicated to my {ate parents :No
Page 5 and 6:
the positive specimens by sucrose g
Page 7 and 8:
Declaration This study represents o
Page 9 and 10:
ACKNOWLEDGEMENTS The author wishes
Page 11 and 12:
Table of Contents Page CHAPTER 1 -
Page 13 and 14:
4.2.1. Animal Sourcing and Care ...
Page 15 and 16:
APPENDIX 8 List of enzyme systems u
Page 17 and 18:
List of Tables Page Table 1.1 Commo
Page 19 and 20:
List of Plates Page Plate 2.1 An eo
Page 21 and 22:
ABBREVIATIONS AND UNITS OF MEASUREM
Page 23 and 24:
agi/is in 1882. In 1914, Alexeieff
Page 25 and 26:
unique about Giardia in humans, whi
Page 27 and 28:
To-date, use of the different speci
Page 29 and 30:
Differentiation into the cyst stage
Page 31 and 32: 1.3 Transmission 1.3.1 Human hosts
Page 33 and 34: Owen, 1984) 1.3. 2 The Zoonosis of
Page 35 and 36: 1.4 Distribution The morbidity and
Page 37 and 38: children by Schutte et al. in 1981
Page 39 and 40: of (a) the enormous absorptive capa
Page 41 and 42: Ig M (100% of patients), IgG (70%),
Page 43 and 44: chymotrypsin) between different iso
Page 45 and 46: impact on the physical growth of 29
Page 47 and 48: Figure 1.3. Transmission Electron m
Page 49 and 50: among children between the ages of
Page 51 and 52: where immunocompromised mice have p
Page 53 and 54: up to 4 distinct genotypes within e
Page 55 and 56: in initiation of infection (excysta
Page 57 and 58: In order to address these and many
Page 59 and 60: multiple stool examinations in 4 of
Page 61 and 62: 2.2 MATERIALS AND METHODS 2.2.1 Spe
Page 63 and 64: Table 2.1. Semi-quantitative assess
Page 65 and 66: 2.2.3.2 The modified Zinc sulphate
Page 67 and 68: Preliminary work with five samples
Page 69 and 70: % Viability = unstained cysts/total
Page 71 and 72: Table 2.3. Prevalence of Giardia in
Page 73 and 74: Table 2. 4. Monthly summary of stoo
Page 75 and 76: spp (59%). Other parasites less fre
Page 77 and 78: Observations • A large proportion
Page 79 and 80: Plate 2.1. An eosin-stained prepara
Page 81: 2.4 DISCUSSION In terms of yield, i
Page 85 and 86: ecognised (on unstained preparation
Page 87 and 88: cultivation in vitro (Kasprzak & Ma
Page 89 and 90: 3.2 MATERIALS AND METHODS Three exc
Page 91 and 92: 3.2.3 The modified Acid Pepsin meth
Page 93 and 94: • After 15 minutes incubation: Ma
Page 95 and 96: Plate 3.2 (b) A completely excysted
Page 97 and 98: Twenty-four batches of cysts (71 %
Page 99 and 100: 3.3.3 The modified Acid Pepsin excy
Page 101 and 102: 3.4 DISCUSSION Since our source of
Page 103 and 104: an unreliable indicator of viabilit
Page 105 and 106: propagating Giardia for subsequent
Page 107 and 108: 4.2 MATERIALS AND METHODS 4.2.1. An
Page 109 and 110: A litter comprising of 7 C57BU6 mic
Page 111 and 112: for attached trophozoites and maint
Page 113 and 114: days pi. However, accurate quantifi
Page 115 and 116: Table 4.4. Summary of the inoculati
Page 117 and 118: not be infected in comparison with
Page 119 and 120: A proportionately higher percentage
Page 121 and 122: These findings strongly suggest tha
Page 123 and 124: CHAPTERS IN VITRO CULTURE OF GIARDI
Page 125 and 126: Diamond et al.'s (1978) medium. He
Page 127 and 128: Majewska, 1985) United States (Nash
Page 129 and 130: were evaluated. 5,2,1,2 Biosate Bio
Page 131 and 132: Table 5.1 Outlines a relative semi-
Page 133 and 134:
dislodged by chilling the culture t
Page 135 and 136:
Table 5.2. Sensitivity to Ciproflox
Page 137 and 138:
Table 5.3. Summary results of in vi
Page 139 and 140:
Once established in culture for a l
Page 141 and 142:
Plates 5.3 and 5.4 Confluent growth
Page 143 and 144:
difficult to produce viable culture
Page 145 and 146:
dominance of certain genotypes unde
Page 147 and 148:
Cryopreservation and successful ret
Page 149 and 150:
adjusted to 5°C per minute from am
Page 151 and 152:
6.3 RESULTS Trophozoites have been
Page 153 and 154:
Table 6.1. A longevity record of sa
Page 155 and 156:
Diamond (1995) stated that an impor
Page 157 and 158:
into two categories. One group cont
Page 159 and 160:
technique to the first local (South
Page 161 and 162:
for Giardia Iysates. These included
Page 163 and 164:
4. To exclude the presence of bacte
Page 165 and 166:
Plate 7.1 Banding pattern of 8 seri
Page 167 and 168:
PGM activity was displayed by Giard
Page 169 and 170:
Plate 7.6. Hexokinase Lane 1. Unino
Page 171 and 172:
Plate 7.8. Phosphogluconate dehydro
Page 173 and 174:
stably expressed between different
Page 175 and 176:
techniques, which would allow diffe
Page 177 and 178:
Belosevic M, Faubert GM, MacLean JD
Page 179 and 180:
Farthing MJG, Mata L, Urrutia JJ, K
Page 181 and 182:
Heidelberg pp.397-398. Hiatt RA, Ma
Page 183 and 184:
patients with X-linked agammaglobul
Page 185 and 186:
Press, Calgary. pp 57-58. Nash TE,
Page 187 and 188:
of Entamoeba histolytica in a group
Page 189 and 190:
Wolfe M. S.1979. Giardiasis. Sympos
Page 191 and 192:
APPENDICES APPENDIX 1 Information t
Page 193 and 194:
Unayo imvume yokunqaba ukungenela l
Page 195 and 196:
Appendix 3 Excystation and culture
Page 197 and 198:
Appendix 4 Results of excystation a
Page 199 and 200:
Appendix 5 Results of in vitro (aci
Page 201 and 202:
Key to Appendix 5 *Replicated inocu
Page 203 and 204:
Appendix 7 Preparation of culture m
Page 205 and 206:
Appendix 8 List of enzyme systems u
Page 207 and 208:
Appendix 9 Appendix (9a) Preparatio
Page 209:
Appendix 10. Quantitative descripti
show all

in vitro culture and isoenzyme analysis of giardia lamblia

Create successful ePaper yourself

Delete template?

Save as template?