A study of tubercular lymphadenitis: A comparison of various laboratory diagnostic modalities with a special reference to tubercular polymerase chain reaction.

Objective: The purpose of our study was to compare various laboratory diagnostic methods, namely histopathological examination, Ziehl-Neelsen (ZN) stain, AFB culture by conventional Lowenstein-Jensen (LJ) method and fluorescence-based mycobacterial growth indicator tube (MGIT) technique and polymerase chain reaction (PCR) in clinically suspected cases of tubercular lymphadenitis. Materials and Methods: A total of 65 lymph nodes biopsied from patients clinically suspected of having tubercular lymph nodes were included. Specimens were processed for AFB culture after NaOH-NALC concentration and inoculation on LJ medium and using the MGIT system. PCR was performed on all specimens using a commercial nested PCR kit targeting IS6110 insertion element of Mycobacterium tuberculosis complex. All lymph node specimens were subjected to histopathological examination. Results: Of the 65 lymph nodes, 37 (56.9%) were positive on MGIT culture and 45 (69.2%) were positive by PCR. Histopathology showed maximum sensitivity (96%) but with compromised specificity (78.5%). PCR showed 90.1% sensitivity and 100% specificity. The mean turnaround time for mycobacterial growth in smear negative specimens was 30 days determined by LJ and 20 days by MGIT techniques. Conclusion: PCR is a rapid and useful method for diagnosis of TB lymphadenitis and definitely increases the positive predictive value of a positive histopathology report. MGIT is better than LJ culture as regards time to positivity and higher yield.

PEFR in pregnancy: a longitudinal study.

Peak expiratory flow rates (PEFR) were measured in 60 pregnant women aged 20-28 years (average 24 yrs) height between 130-160 cm (average 154.5 cm), each month beginning from 3rd month of gestation and also 8-10 weeks postpartum using, Wright's Peak Flow Meter. The PEFR declined from 329.12 +/- 4.40 lpm in 3rd month to 286.22 +/- 3.81 lpm in 9th month of gestation and increased to 347.86 +/- 2.93 lpm in postpartal period. A similar, declining trend is also observed in other Indian studies. However, the values are lower than those observed in Europeans. Also no change in PEFR during pregnancy was observed in an European study. The PEFR in our study regressed at a rate of 6.68 lpm/month of gestation and 5.49 lpm/kg increase in weight throughout pregnancy. The correlation with forced vital capacity (FVC) and forced expiratory volume in first second (FEV1) is non-significant throughout pregnancy. The anaemic pregnant women showed lower PEFR when compared with PEFR of nonanaemic pregnant women, but showed a similar declining trend throughout pregnancy.

A longitudinal study of pulmonary function tests during pregnancy.

The study deals with evaluation of pulmonary function status in fifty normal pregnant women tested monthly. The parameters studied were Vital Capacity (VC) Forced Vital Capacity (FVC) and Forced Expiratory Volume in 1st second (FEV1) using Vitalograph Spirometer; tidal volume (VT), inspiratory capacity (IC) and expiratory reserve volume (ERV) using Expirograph and resting minute ventilation (VE) using Tissot's spirometer. Control values were obtained in the same subject 8-10 weeks after delivery. The increase seen in VT, VE and IC was very highly significant. The small increment in frequency of respiration is significant and the declining trend observed in ERV is very highly significant. VC and FVC were maintained by the rise in IC and a concomitant fall in ERV. Rise in VC is attributed mainly to rise in VT than rise in frequency. The results suggest that though pulmonary function is altered during pregnancy, it is not compromised and hence does not induce any mechanical stress on the respiratory efficiency of the pregnant woman.

Serum level of iron and transferrin in pregnancy and postpartum period.

This study presents a composite picture of haemoglobin (Hb), serum level of iron (SI), total iron binding capacity (TIBC) and percent iron saturation of transferrin in women during different trimesters of pregnancy and postpartum period. The results were correlated with age and parity. A total of 75 subjects, 15 from each trimester and 15 postpartal, were studied and compared with 15 nonpregnant normal subjects. Signs of increased iron demand, increased iron turnover and obvious iron deficiency, were demonstrated throughout pregnancy, by decrease in haemoglobin, SI, percent iron saturation of transferrin and increased TIBC; especially in older age group and multigravidae. SI, TIBC and percent iron saturation of transferrin are more sensitive indices of iron status and provide us an opportunity to replenish iron stores of an iron deficient pregnant mother at an earlier date thus preventing anaemia.

Action of some new insect growth regulators on mosquito vectors. Part II: Geraniol based diethers.

Biological activity of saturated diethers viz. 1-benzyloxy/phenoxy-8-alkoxy and 1-alkoxy-8-benzyloxy-3,7-dimethyl-1, 8-octanes (IIa-IIq) prepared from Geraniol, were studied on three mosquito species and the bug Dysdercus koenigii. These diethers exhibited oviposition deterrent and developmental inhibition activities of greater magnitudes than the compounds based on citronellol reported in Part I of this paper. Some of these new compounds inhibit development of mosquitoes at 0.05 ppm and deter oviposition at 0.05 per cent doses. Tests were extended to field simulated conditions in selected cases.

Action of some insect growth regulators on mosquito vectors: Part I--Citronellol based diethers.

New series of compounds starting from common terpenoids (Geraniol, citronellol) have been examined for biological activity on mosquito larvae. Many of these exhibited development disruption on eggs as well larvae. Some also affected adult oviposition behaviour. Developmental disturbances were classified as JH type by inducing typical metamorphosis inhibition in Dysdercus koenigii in the standard Hemipteran JH bioassay. Where indicated simulated field trials were also undertaken. This report describes results of bioevaluation of the citronellol based compounds. The results indicate that these show multifarious activity against mosquitoes but at relatively high doses, suggesting that exploration of further structural variety is needed before truly promising analogues can be obtained.

Cyclopcidal activity of some new insect growth regulators.

A series of synthetic terpenoid diethers, with known mosquito development inhibitory activity, were tested for cyclopcidal activity against adult cyclops, Mesocyclops leuckarti. Four among these exhibited promising activity comparable to that of the conventional organophosphate, temephos, thus providing for the first time a possible reserve arsenal for the control of the guineaworm disease vector.