Nitrous oxide speeds the reduction of distressing intrusive memories in an experimental model of psychological trauma.

BACKGROUND: Post-traumatic stress disorder (PTSD) involves maladaptive long-term memory formation which underlies involuntary intrusive thoughts about the trauma. Preventing the development of such maladaptive memory is a key aim in preventing the development of PTSD. We examined whether the N-methyl d-aspartate receptor (NMDAR) antagonist gas nitrous oxide (N2O) could reduce the frequency of intrusive memories by inhibiting NMDAR-dependent memory consolidation in a laboratory analogue of psychological trauma. METHOD: Participants were randomized to inhale N2O (N = 25) or medical air (N = 25) after viewing a negatively valenced emotional film clip ('trauma film'). Participants subsequently completed a daily diary assessing frequency of intrusive thoughts relating to the film clip. A week later, participants completed an explicit memory recall task related to the film. RESULTS: Post-encoding N2O sped the reduction in intrusive memory frequency, with a significant reduction by the next day in the N2O group compared to 4 days later in the air group. N2O also interacted with post-film dissociation, producing increased intrusion frequency in those who were highly dissociated at baseline. Sleep length and quality the night after viewing the film did not differ between the groups. CONCLUSION: N2O speeds the reduction of intrusive analogue trauma memory in a time-dependent manner, consistent with sleep-dependent long-term consolidation disruption. Further research with this drug is warranted to determine its potential to inoculate against enduring effects of psychological trauma; however, caution is also urged in dissociated individuals where N2O may aggravate PTSD-like symptomatology.

Glycosylated Hemoglobin in Different Levels of BMI.

Body mass index is an inexpensive and easy method of screening for weight categories that may lead to health problems. Increased BMI in overweight and obese persons is directly associated with an increase in metabolic disease, such as type 2 diabetes mellitus. This Analytical cross sectional study was undertaken to assess the relation between increasing BMI and glycemic control of body through measuring glycosylated hemoglobin. This study was carried out in the Department of Physiology, Mymensingh Medical College, Mymensingh, Bangladesh from July 2011 to June 2012 on 180 equally divided male and female persons between the age of 25 to 55 years. Age more than 55 years and less than 25 years and diagnosed case of hypothyroidism, cushing's syndrome, polycystic ovary, antipsychotic drug user and regular steroid users were excluded. Non probability purposive type of sampling technique was used for selecting the study subjects. Measurement of body mass index was done as per procedure. Glycosylated hemoglobin was estimated by Boronate Affinity method. Statistical analysis was done by SPSS (version 17.0). Data were expressed as Mean (±SE) and statistical significance of difference among the groups were calculated by unpaired student's 't' test and Pearson's correlation coefficient tests were done as applicable. There was no significant difference of glycosylated hemoglobin level between control and study groups. But there was positive correlation within each group (r=0.255, 0.37 and 0.39 in control, overweight and obese respectively). The observed positive correlation between BMI and glycosylated hemoglobin emphasizes the maintenance of normal BMI to prevent early onset of type 2 diabetes mellitus. Health education activities highlighting the danger of becoming overweight and obese should be undertaken.

Fasting Serum Glucose Level in Postmenopausal Bangladeshi Women.

The study was done to find out the causes that changes the fasting serum glucose level in postmenopausal women. This was descriptive type of cross sectional study carried out over a period of one year from July 2014 to June 2015 in the department of physiology, Mymensingh Medical College, Mymensingh. Women of reproductive age (25-45 years) and clinically diagnosed 100 menopausal women (45-70 years) were included for this study. Convenience type of sampling technique was used for selecting the study subjects. Measurement of fasting serum glucose was done by GOD-PAP method. Data were expressed as mean±SD and statistical significance of difference among the groups were calculated by unpaired student's 't' test. The mean±SD of serum glucose in menopausal women were significant at 1% level of probability than women of reproductive age. This study revealed that postmenopausal women showed higher levels of fasting serum glucose level. Fasting blood sugar level between the study & control group were 7.69±2.37 and 4.59±0.73 and the difference was statistically significant.

Serum Glucose Level in First and Third Trimester of Pregnancy.

In the present study serum glucose were estimated in pregnant women during the first trimester of pregnancy and third trimester of pregnancy to observe the frequency of hyperglycemia during pregnancy and to assess the incidence of gestational diabetes mellitus. This study was a cross sectional study, carried out in the Department of Physiology of Mymensingh Medical College, Mymensingh from July 2014 to June 2015. For this purpose, total 300 women with age ranged from 18 to 35 years were selected and divided into 100 healthy non pregnant women as control group and 200 normal pregnant women as study group. Study group was further divided into 100 pregnant women in first trimester of pregnancy and 100 pregnant women in third trimester of pregnancy. Diagnosed case of type I and type II diabetes, hypothyroidism, cushing's syndrome, polycystic ovary, antipsychotic drug users, regular steroid users were excluded from this study. Serum glucose was evaluated by the glucose-oxidase principle by GOD-PAP method in women with 1st trimester of pregnancy, 3rd trimester of pregnancy and in non pregnant women. Statistical analysis of data was done by unpaired student's t test. The results showed that the serum glucose levels increased significantly in third trimester and the value is not significant in first trimester. The increasing frequency of serum glucose level in third trimester may predispose the women to hyperglycemia of pregnancy or gestational diabetes mellitus.

Blood Pressure in Third Trimester of Pregnancy.

Pregnancy is a great stressful physiological condition in women during their reproductive period. During pregnancy several hemodynamic, biochemical and hematological modifications occur as a part of the physiological adaptation of the body. Changes in blood pressure occur in third trimester of pregnancy, which may be associated with increased maternal and infant mortality and morbidity. This cross-sectional study was carried out in the Department of Physiology, Mymensingh Medical College, Mymensingh, from July 2013 to June 2014. Study subjects were selected by following purposive sampling procedure and the protocol of this study was approved by Institutional Ethics Committee (IEC) of Mymensingh. This study enrolled 100 pregnant women of third trimester of pregnancy and 100 aged matched non-pregnant women from Mymensingh district. Mean systolic blood pressure in study group were 124.8±14.51 mm of Hg and in control group were 106.50±10.67 mm of Hg, which was statistically increased. Diastolic blood pressure in study group was 83.00±13.37 mm of Hg and in control group 71.05±7.12 mm of Hg, which was also statistically significant. The changes in blood pressure in third trimester of pregnancy is the major concern of developing the risk of pre-eclampsia & eclampsia, and increased prevalence of IUGR, pre-maturity and perinatal mortality. This study reveals significant changes of blood pressure during third trimester of pregnancy.

Blood pressure and serum creatinine in obese female.

Obesity is increasing in developed as well as in developing countries. This analytical cross sectional study was carried out to document the relation between blood pressure, serum creatinine and body mass index in female and to assess potential health differences among obese female and normal weight female. This study was done in the Department of Physiology, Mymensingh Medical College, Mymensingh, Bangladesh from July 2012 to June 2013. Seventy female persons volunteered as subjects. Among them 35 were within normal weight (BMI 18.5-24.9kg/m²) and 35 were obese (BMI≥30kg/m²). Non probability purposive type of sampling technique was used to select the subjects. Measurement of body mass index and blood pressure were done as per procedure. Serum creatinine level was estimated by enzymatic colorimetric method. The results were calculated and analyzed by using SPSS (statistical package for social science, version 17.0), scientific electronic calculator and simultaneously with a computer assisted program like Microsoft excel. Unpaired 't' test was applied to find the significance of difference regarding serum creatinine and blood pressure levels in obese female. The value of p was 1% to indicate highly significant and 5% to indicate simply significant or statistically significant. The mean±SE of systolic blood pressure, diastolic blood pressure and serum creatinine levels were 135.71±1.58mmHg, 88.74±0.95mmHg and 1.03±0.01mg/dl respectively; significant at 1% level for obese group of BMI (p<0.0001). The examinations and biochemical investigations revealed that high BMI is significantly related to increased levels of serum creatinine & blood pressure in obese female which indicate the obese subjects are prone to cardiovascular & metabolic risk.

Study on Serum Albumin in Third Trimester of Pregnancy.

Various hormones can cause marked changes in pregnant woman's appearance. Decreased level of serum albumin occurs in third trimester of pregnancy, which may be associated with increased maternal and infant mortality and morbidity. So, this study was carried out to evaluate and assess the level of serum albumin in third trimester of pregnancy. This cross-sectional study was carried out in the Department of Physiology Mymensingh Medical College, Mymensingh. This study enrolled 100 pregnant women of third trimester of pregnancy and 100 aged matched non-pregnant women from Mymensingh district. In this study serum albumin level in study group were 33.41 ± 4.62gm/l and in control group were 37.09 ± 4.21 gm/l, which was statistically decreased. The lower level of serum albumin in third trimester of pregnancy is the major concern of development of physiological edema during pregnancy and may be associated with pre-eclampsia.

Fasting serum glucose and glycosylated hemoglobin level in obesity.

Obesity is a condition in which the body fat stores are increased to an extent which impairs health and leads to serious health consequences. The amount of body fat is difficult to measure directly, and is usually determined from an indirect measure - the body mass index (BMI). Increased BMI in obese persons is directly associated with an increase in metabolic disease, such as type 2 diabetes mellitus. This Analytical cross sectional study was undertaken to assess the relation between obesity and glycemic control of body by measuring fasting serum glucose and glycosylated hemoglobin. This study was carried out in the Department of Physiology, Mymensingh Medical College, Mymensingh from 1st July 2011 to 30th June 2012 on 120 equally divided male and female persons within the age range of 25 to 55 years. Age more than 55 years and less than 25 years and diagnosed case of Hypothyroidism, Cushing's syndrome, polycystic ovary, Antipsychotic drug user and regular steroid users were excluded. Non probability purposive type of sampling technique was used for selecting the study subjects. Measurement of body mass index was done as per procedure. Fasting serum glucose was estimated by glucose oxidase method and Glycosylated hemoglobin by Boronate Affinity method. Statistical analysis was done by SPSS (version 17.0). Data were expressed as Mean±SE and statistical significance of difference among the groups were calculated by unpaired student's 't' test and Pearson's correlation coefficient tests were done as applicable. The Mean±SE of fasting serum glucose was significant at 1% level (P value <0.001) for obese group of BMI. There was no significant difference of glycosylated hemoglobin level between control and study groups. But there was positive correlation within each group. Fasting serum glucose also showed a bit stronger positive correlation with BMI. Both obese male and female persons showed higher levels of fasting serum glucose and glycosylated hemoglobin. The observed positive correlation between BMI with fasting serum glucose and glycosylated hemoglobin emphasizes the importance of maintenance of normal BMI to prevent early onset of type 2 diabetes mellitus.

Blood pressure in different levels of BMI.

Body mass index (BMI) is an inexpensive and easy-to-perform method of screening for weight. In recent years, non-communicable diseases (NCD) like obesity, hypertension and Type-2 diabetes are on the increase in the developed and developing nations. This Analytical cross sectional study was done to appraise the effect of overweight and obesity in development of high blood pressure. This study was carried out in the Department of Physiology, Mymensingh Medical College, Mymensingh, Bangladesh from 1st July 2011 to 30th June 2012 on 180 equally divided male and female persons between the ages of 25 to 55 years. Non probability purposive type of sampling technique was used for selecting the study subjects. Measurement of body mass index and blood pressure were done as per procedure. Data were expressed as mean±SE and statistical significance of difference among the groups were calculated by unpaired student's 't' test and Pearson's correlation coefficient tests were done as applicable. The mean±SE of Systolic blood pressure were significant at 1% level for both overweight and obese groups of BMI (p<0.001). The mean±SE of Diastolic blood pressure were significant at 1% level for overweight group (p<0.009) and 5% level for obese group (p<0.02). Systolic blood pressure and Diastolic blood pressure showed positive correlation with BMI where in case of Systolic blood pressure it was stronger. This study revealed that overweight and obese persons showed higher level of blood pressure.

Susceptibility anisotropy in an iron arsenide superconductor revealed by x-ray diffraction in pulsed magnetic fields.

In addition to unconventional high-T(c) superconductivity, the iron arsenides exhibit strong magnetoelastic coupling and a notable electronic anisotropy within the a-b plane. We relate these properties by studying underdoped Ba(Fe(1-x)Co(x))2As2 by x-ray diffraction in pulsed magnetic fields up to 27.5 T. We exploit magnetic detwinning effects to demonstrate anisotropy in the in-plane susceptibility, which develops at the structural phase transition despite the absence of magnetic order. The degree of detwinning increases smoothly with decreasing temperature, and a single-domain condition is realized over a range of field and temperature. At low temperatures we observe an activated behavior, with a large hysteretic remnant effect. Detwinning was not observed within the superconducting phase for accessible magnetic fields.

Studies on the identification and control of pathogen Saprolegnia in selected Indian major carp fingerlings at mid hill altitude.

The Indian major carp cultured in ponds in the North Eastern hilly states of India frequently suffer from fungal disease during winter months resulting in mass mortality. This study examined the pathogenic fungi isolated from farmed raised Indian major carp fingerlings and identified as Saprolegnia. For treatment, the diseased fish were exposed to 4g salt per litre of water for 2 min followed by dip treatment with 5ppm KMnO4 for 10 min, thrice every week for a period of 6 weeks. The treatment resulted in recovery from the disease after 6 weeks from the beginning of treatment. Soon after recovery, the pond management practices such as removal of pond bottom soil, application of lime and replenishment with freshwater were followed in the infected ponds. Our study concluded that rapid decrease in pond water temperature from 22 to 8 degrees C that remains low for months together coupled with increased water pH (9) and decreas dissolved oxygen (4ppm) causes saprolegniasis to the fingerlings of Indian major carps.

Effect of pre-freeze addition of cysteine hydrochloride and reduced glutathione in semen of crossbred Jersey bulls on sperm parameters and conception rates.

This study was aimed to assess the effect of pre-freeze addition of cysteine hydrochloride and glutathione (GSH) on post-thaw sperm functional parameters and field fertility. The experimental bulls (n = 6) aged 4-6 years were used for this study. A total of 36 ejaculates (six ejaculates per bull) were collected and divided into three groups, group I (control), group II (5 mm cysteine hydrochloride) and group III (5 mm GSH). The extended semen samples with and without additives were filled in mini straw using automatic filling and sealing machine and cryopreserved in liquid nitrogen. Post-freeze seminal traits were recorded after thawing at 37°C for 30 s. The curvilinear velocity (VCL) and amplitude of lateral head displacement values were significantly (p < 0.05) higher in GSH than the cysteine and control groups. Post-thaw plasmalemma integrity was significantly (p < 0.01) higher in GSH group when compared to cysteine and control groups. The loss of acrosomal integrity was significantly (p < 0.01) lower in GSH than in cysteine and control groups. Addition of GSH non-significantly (p = 0.1) improved mitochondrial membrane potential (MMP) (per cent) than control group. This study indicates that the addition of cysteine and GSH suggestive (p = 0.08) of reducing lipid peroxide levels. The conception rate (%) in glutathione group was significantly (p < 0.05) higher than that in cysteine (68 vs 58) and control (49) groups. The post-thaw sperm progressive forward motility (r = 0.4) had moderate, but no significant correlation with conception rate. However, post-thaw straight-line velocity (r = 0.7), loss of acrosomal integrity (r = -0.8) and MMP (r = 0.9) had significant (p < 0.05) correlation with field fertility. This study indicates that the use of glutathione as semen additive may be used for improving post-thaw semen quality and overall augmentation of pregnancy in cows.

Polysomnographic profile in a sleep laboratory in Kolkata: a retrospective analysis of 714 cases.

In this retrospective analysis, all patients (n=714; male=590; female=124 and female male ratio = 1: 4.76) came to Pulsar, a sleep laboratory of Kolkata, for polysomnography during ten years period were analyzed. More than half (62.46%) cases were between 41-60 years and 14.43% cases between 61-80 years age group. Fifty-two percent cases were referred by pulmonologists, followed by internist (15%), and 7% cases were self referred. Though obstructive sleep apnea was responsible for increased cardiovascular mortality and resistant hypertension, only 4% cases were referred by cardiologists. We observed hypertension as co-morbidity in 52.63% cases and ischemic heart disease in 22.83% cases. Snoring was the presenting complain in 98.88% cases, chocking was present in 48.88% cases and excessive daytime sleepiness was found in 96.64% cases. Females showed comparatively higher frequency of sleep disordered breathing than males with increasing basal metabolic rate. Nocturnal fall of SPO2 below 90% was observed in 86.97% of study population. We found abnormal respiratory disturbance index (> 5/hr of sleep) in 84.59% of our patients, normal respiratory disturbance index (< or = 5/hr of sleep) in 9.94% cases and isolated nocturnal hypoxemia in 5.46% cases (74.36% of the last category having obstructive airway disease). Snoring with respiratory disturbance index (RDI) < or = 5/hr was observed in 102 cases, of them 81.37% had simple snoring without significant arousal whereas 18.63% had multiple sleep fragmentation. We estimated that 84.06% of males, 87.10% of females and 84.59% of study population had obstructive sleep apnea. Split night polysomnography was performed in 362 cases, and of them 15.47% cases could not tolerate continuous positive airway pressure (CPAP) due to local or psychological reasons. In the present one time split-night CPAP titration study, we could not correct OSA in 19.06% subjects. Inadequate correction of hypoxemia due to co-morbid condition like COPD, asthma, obesity, hypothyroidism was the main responsible factor (49.28%). Treatment with CPAP was effective in 68.23% cases in first attempt. More than half of the cases (62.42%) required 10 cm of H20 or less CPAP.

Wunderlich's syndrome with hepatic angiomyolipoma in tuberous sclerosis.

We present a patient of tuberous sclerosis complex with bilateral renal angiomyolipoma and hepatic angiomyolipoma with spontaneous retroperitoneal hemorrhage from right angiomyolipoma (Wunderlich's syndrome). Nephron preserving approach was tried but the right kidney could not be salvaged. Hepatic angiomyolipoma was managed conservatively. Wunderlich's syndrome has been found in around 10% of cases of renal angiomyolipomas. Hepatic Angiomyolipoma is a benign mesenchymal neoplasm of the liver which is rarely reported in literature.

Laparoscopic versus open pyeloplasty: Comparison of two surgical approaches -- a single centre experience of three years.

BACKGROUND: Ureteropelvic junction obstruction (UPJO) causes hydronephrosis and progressive renal impairment may ensue if left uncorrected. Open pyeloplasty remains the standard against which new technique must be compared. We compared laparoscopic (LP) and open pyeloplasty (OP) in a randomized prospective trial. MATERIALS AND METHODS: A prospective randomized study was done from January 2004 to January 2007 in which a total of 28 laparoscopic and 34 open pyeloplasty were done. All laparoscopic pyeloplasties were performed transperitoneally. Standard open Anderson Hynes pyeloplasty, spiral flap or VY plasty was done depending on anatomic consideration. Patients were followed with DTPA scan at three months and IVP at six months. Perioperative parameters including operative time, analgesic use, hospital stay, and complication and success rates were compared. RESULTS: Mean total operative time with stent placement in LP group was 244.2 min (188-300 min) compared to 122 min (100-140 min) in OP group. Compared to OP group, the post operative diclofenac requirement was significantly less in LP group (mean 107.14 mg) and OP group required mean of (682.35 mg). The duration of analgesic requirement was also significantly less in LP group. The postoperative hospital stay in LP was mean 3.14 Days (2-7 days) significantly less than the open group mean of 8.29 days (7-11 days). CONCLUSION: LP has a minimal level of morbidity and short hospital stay compared to open approach. Although, laparoscopic pyeloplasty has the disadvantages of longer operative time and requires significant skill of intracorporeal knotting but it is here to stay and represents an emerging standard of care.

Nitrous oxide may interfere with the reconsolidation of drinking memories in hazardous drinkers in a prediction-error-dependent manner.

Weakening drinking-related reward memories by blocking their reconsolidation is a potential novel strategy for treating alcohol use disorders. However, few viable pharmacological options exist for reconsolidation interference in humans. We therefore examined whether the NMDA receptor antagonising gas, Nitrous Oxide (N2O) could reduce drinking by preventing the post-retrieval restabilisation of alcohol memories in a group of hazardous drinkers. Critically, we focussed on whether prediction error (PE; a key determinant of reconsolidation) was experienced at retrieval. Sixty hazardous drinkers were randomised to one of three groups that retrieved alcohol memories either with negative PE (Retrieval + PE), no PE (Retrieval no PE) or non-alcohol memory retrieval with PE (No-retrieval +PE). All participants then inhaled 50% N2O for 30 min. The primary outcome was change in beer consumption and alcohol cue-driven urge to drink from the week preceding manipulation (baseline) to the week following manipulation (test). The manipulation did not affect drinking following the intended retrieval+/- PE conditions However, a manipulation check, using a measure of subjective surprise, revealed that the group-level manipulation did not achieve the intended differences in PE at retrieval. Assessment of outcomes according to whether alcohol-relevant PE was actually experienced at retrieval, showed N2O produced reductions in drinking in a retrieval and PE-dependent fashion. These preliminary findings highlight the importance of directly testing assumptions about memory reactivation procedures in reconsolidation research and suggest that N2O should be further investigated as a potential reconsolidation-blocking agent.

The effects of cannabidiol on impulsivity and memory during abstinence in cigarette dependent smokers.

Acute nicotine abstinence in cigarette smokers results in deficits in performance on specific cognitive processes, including working memory and impulsivity which are important in relapse. Cannabidiol (CBD), the non-intoxicating cannabinoid found in cannabis, has shown pro-cognitive effects and preliminary evidence has indicated it can reduce the number of cigarettes smoked in dependent smokers. However, the effects of CBD on cognition have never been tested during acute nicotine withdrawal. The present study therefore aimed to investigate if CBD can improve memory and reduce impulsivity during acute tobacco abstinence. Thirty, non-treatment seeking, dependent, cigarette smokers attended two laboratory-based sessions after overnight abstinence, in which they received either 800 mg oral CBD or placebo (PBO), in a randomised order. Abstinence was biologically verified. Participants were assessed on go/no-go, delay discounting, prose recall and N-back (0-back, 1-back, 2-back) tasks. The effects of CBD on delay discounting, prose recall and the N-back (correct responses, maintenance or manipulation) were null, confirmed by a Bayesian analysis, which found evidence for the null hypothesis. Contrary to our predictions, CBD increased commission errors on the go/no-go task. In conclusion, a single 800 mg dose of CBD does not improve verbal or spatial working memory, or impulsivity during tobacco abstinence.

Hemato-biochemical alterations and urinalysis in dogs suffering from benign prostatic hyperplasia.

AIM: The study was designed to evaluate the hemato-biochemical alterations, urinalysis along with histomorphological and histological changes of prostate glands in dogs affected with benign prostatic hyperplasia (BPH) in and around Bhubaneswar, Odisha, India. MATERIALS AND METHODS: In toto, 445 dogs presented to the Teaching Veterinary Clinical Complex of the College of Veterinary Sciences and Animal Husbandry, one Government Veterinary Hospital and two pet clinics in and around Bhubaneswar screened for the presence of BPH. Most of the 57 dogs were 6 years and above as reported by the owners. Only 57 dogs found positive for BPH basing on the presence of typical clinical signs subjected for a detailed hemato-biochemical study. Most of the 57 dogs were 6 years and above as reported by the owners. Routine and microscopic urinalyses were done as per the routine procedure. Histomorphological evaluations of prostate glands were done through manual rectal palpation. Histological examinations of prostate tissue sections of two dead dogs were conducted with routine hematoxylin and eosin stain. RESULTS: The study revealed about 12.8% (57/445) of dogs was suffering from BPH. Typical clinical signs - such as passing small thin tape-shaped feces, holding tail away from backward, tenesmus, and straining during urination and defecation - were seen in most of the cases. Urine samples of affected dogs were positive for glucose, occult blood, and protein. A significant decrease in lymphocytes and increase in eosinophil counts in dogs with BPH was recorded. Serum biochemical analysis showed a nonsignificant increase in creatinine and blood urea nitrogen with a significant decrease in total protein, albumin, globulin, A:G ratio. Histology of prostate glands collected during postmortem was characterized by fibrosis of prostate gland, and hyperplasia of the acinar epithelium. CONCLUSIONS: High rate of the prevalence of BPH in dogs poses an alarming condition which if diagnosed at an early stage can certainly prolong the longevity of the dogs.

Catalytic activity of acid and base with different concentration on sol-gel kinetics of silica by ultrasonic method.

The effects of both acid (acetic acid) and base (ammonia) catalysts in varying on the sol-gel synthesis of SiO2 nanoparticles using tetra ethyl ortho silicate (TEOS) as a precursor was determined by ultrasonic method. The ultrasonic velocity was received by pulsar receiver. The ultrasonic velocity in the sol and the parameter ΔT (time difference between the original pulse and first back wall echo of the sol) was varied with time of gelation. The graphs of ln[ln1/ΔT] vs ln(t), indicate two region - nonlinear region and a linear region. The time corresponds to the point at which the non-linear region change to linear region is considered as gel time for the respective solutions. Gelation time is found to be dependent on the concentration and types of catalyst and is found from the graphs based on Avrami equation. The rate of condensation is found to be faster for base catalyst. The gelation process was also characterized by viscosity measurement. Normal sol-gel process was also carried out along with the ultrasonic one to compare the effectiveness of ultrasonic. The silica gel was calcined and the powdered sample was characterized with scanning electron microscopy, energy dispersive spectra, X-ray diffractogram, and FTIR spectroscopy.