Sensitizers commonly causing allergic contact dermatitis from cosmetics.
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Adolescent↗
Biomedical subjects
V K Sharma
Publications and source records attributed to V K Sharma.
Growth inhibitory and antifeedant activity of extracts from Melia dubia to Spodoptera litura and Helicoverpa armigera larvae.
The growth inhibitory activity and deterrency of Melia dubia (Meliaceae) extracts to Spodoptera litura and Helicoverpa armigera were investigated. Artificial diet bioassays using neonate larvae of both S. litura and H. armigera indicated that dichloroethane (DCE) and methanol (Me) extracts of M. dubia inhibited growth in a dose dependent manner. DCE and Me-5II fractions also resulted in 50% deterrency at concentrations of 22.5 and 16.8 micrograms/cm2 respectively against S. litura larvae in a leaf disc-choice test. The DCE-5 fraction was found to be more toxic to larvae (LC50 of 0.65%) than the Me-5II (LC50 of 0.8%), 72 hr after topical application. Both fractions lack contact toxicity, but the deterrent effect persisted for at least 60 hr under laboratory conditions. Although salannin was isolated from the DCE fraction to show antifeedant activity, the physico-chemical characteristics of the active fractions DCE-5 and Me-5II were not identical with either salannin or azadirachtin.
Acetates↗
Comparison of 24-hour intragastric pH using four liquid formulations of lansoprazole and omeprazole.
The results of previous studies evaluating the effect of four liquid formulations of proton-pump inhibitors on 24-hour intragastric pH are described. Patients with a gastrostomy who were resident in a Veterans Affairs medical center or its affiliated nursing home were eligible for enrollment in one of four open-label studies in which each patient served as his own control. Patients underwent 24-hour intragastric pH studies before and after receiving seven consecutive days of one of the following liquid formulations of a proton-pump inhibitor administered once daily: omeprazole granules 20 mg in orange juice, lansoprazole granules 30 mg in orange juice, simplified omeprazole suspension 20 mg, and simplified lansoprazole suspension 30 mg. The suspensions were prepared with 10 mL of 8.4% sodium bicarbonate solution. Mean intragastric pH was measured, as was the time pH stayed above 3.0 and 4.0 during the 24-hour period. Six to 14 patients participated in each study. The mean posttreatment pH was 4.9+/-0.8, 4.7+/-0.6, 4.1+/-1.5, and 5.1+/-1.1 for omeprazole granules in orange juice, lansoprazole granules in orange juice, simplified omeprazole suspension, and simplified lansoprazole suspension, respectively. Both drugs in orange juice maintained pH above 4.0 longer than 14 hours and above 3.0 for close to 20 hours, which are the levels deemed optimal for healing erosive esophagitis and duodenal ulcers, respectively. Simplified lansoprazole suspension maintained pH above those thresholds for the optimal times, but simplified omeprazole suspension did not (20 and 15 hr above 3.0, 17 and 12 hr above 4.0 for lansoprazole and omeprazole, respectively). Further development of liquid formulations of proton-pump inhibitors may have important implications for the treatment of acid-related diseases in patients, including children, who are unable to swallow capsules.
2-Pyridinylmethylsulfinylbenzimidazoles↗
Rapid report: a novel technique for quantitative measurement of free Ca2+ concentration in rat heart mitochondria.
1. The free mitochondrial Ca2+ concentration ([Ca2+]m) in rat heart mitochondria was measured quantitatively by loading the mitochondria with fura-2 and then injecting them into Xenopus laevis oocytes. 2. When oocytes were incubated with a physiological solution, the free cytosolic Ca2+ concentration ([Ca2+]c) in the oocytes was 82 +/- 11 nM (n = 20, mean +/- s.e.m.) and the [Ca2+]m of the injected rat heart mitochondria was 116 +/- 10 nM (n = 18, mean +/- s.e.m.). 3. Inhibition of the oocyte endoplasmic reticular Ca2+-ATPase with thapsigargin produced a transient increase in averaged [Ca2+]c at sub-micromolar concentrations. 4. Injection of cardiac mitochondria blunted the peak and prolonged the duration of thapsigargin-induced [Ca2+]c transients as a result of Ca2+ sequestration by the cardiac mitochondria. 5. These results demonstrate that the present technique provides a new approach for studying [Ca2+]m regulation quantitatively under physiological environments. Furthermore, it clearly shows that cardiac mitochondria can modify the shape of thapsigargin-induced cytosolic Ca2+ pulses in Xenopus oocytes.
Animals↗
Non-gastrointestinal tract associations of Helicobacter pylori infection.
Helicobacter pylori infection is linked to conditions of the upper gastrointestinal tract, including peptic ulcer and gastric adenocarcinoma. It has also been associated with a wide variety of non-gastrointestinal tract conditions. However, the evidence in support of H. pylori infection as a cause of the non-gastrointestinal tract conditions is not widely understood. We reviewed the medical literature for publications and abstracts dealing with putative non-gastrointestinal tract associations of H. pylori infection. We appraised the level of evidence and applied it to an established set of 9 criteria for determining causation. We found that many studies examining a possible causal relationship have been uncontrolled or inadequately controlled. Studies have often failed to control for socioeconomic status. Studies of treating H. pylori infection in patients with these disorders have been poorly designed and inappropriately controlled, and therefore add little to the evidence base. Attention should be focused on appropriate testing for and treatment of H. pylori infection in patients with conditions that are of proven association, notably peptic ulcer disease.
Cardiovascular Diseases↗
Relationship between light intensity and phase resetting in a mammalian circadian system.
The light-induced phase-resetting response of the locomotor activity rhythm in the field mouse Mus booduga was studied at two phases of the circadian cycle known to respond to light stimuli of 15 min duration and 1000 lux intensity with maximum advance (at circadian time 20 [CT20]) and maximum delay phase-shifts (at CT15). The phase-shifts evoked by natural daylight stimuli of various illuminations ranging between 0.001 lux and 10,000 lux and lasting 15 min were estimated. The results clearly demonstrate that the relationship between the phase-shifts and the intensities of light stimuli is nonlinear. Furthermore, a single light stimulus of 0.001 lux, or 0.1 lux intensity for a duration of 15 min, administered at CT20, evoked unequivocal responses; phase delays were observed instead of phase advances. The critical intensities needed for light stimuli of 15 min duration to induce saturating response were calculated and were found to be about 100 lux for CT20 and about 500 lux for CT15. These results suggest that a greater intensity of light is required at the phase CT15 to induce a saturating phase shift than is required at a later phase of the circadian cycle (CT20).
Animals↗
Detection of multiresistant Salmonella typhimurium DT104 using multiplex and fluorogenic PCR.
Salmonella infections continue to cause gastrointestinal and systemic disease throughout the world. Salmonella typhimurium DT104 further poses a major health concern due to its acquisition of resistance to multiple antibiotics. The rapid detection of multiresistant S. typhimurium DT104 would facilitate strategies aimed at controlling this pathogen. We developed a specific and sensitive polymerase chain reaction (PCR) assay that amplifies a segment of DNA that is conserved in multiresistant S. typhimurium DT104. To provide further specificity for this PCR-based diagnostic test, we amplified two other gene fragments that are present in S. typhimurium DT104. A multiplex PCR containing primers for targeted sequences resulted in the amplification of predicted size fragments from S. typhimurium DT104 exhibiting the ACSSuT (ampicillin, chloramphenicol, streptomycin, sulphamethoxazole and tetracycline) or ASSuT resistance phenotypes. A minor modification of the multiplex PCR enabled the detection of other related multiresistant Salmonella such as S. typhimurium U302. To augment the detection process, we also designed a fluorogenic PCR assay that can detect the DNA of multiresistant S. typhimurium DT104 in the presence of excess contaminating bacterial DNA. These results provide a method by which multiresistant S. typhimurium DT104, or potentially the next emerging multiresistant Salmonella, can be accurately detected in only 3-4 h.
Drug Resistance, Microbial↗
Semi-automated fluorogenic PCR assays (TaqMan) forrapid detection of Escherichia coli O157:H7 and other shiga toxigenic E. coli.
Semi-automated detection of Enterohaemorrhagic Escherichia coli (EHEC) O157:H7 and non-O157:H7 Shiga toxin-producing E. coli (STEC) was achieved using fluorogenic polymerase chain reaction (PCR). These PCR assays were designed to amplify 80, 120 and 150 bp regions of virulence genes stx1, stx2 and eaeA, respectively, using specific primers. The fluorogenic probes were used for specific detection of amplified products of the stx1 and stx2 genes of STEC, and the eaeA gene of EHEC O157:H7. For multiplex PCR assay, the three sets of primers and fluorogenic probes were included in one reaction to simultaneously amplify and detect any of the three targeted virulence genes. In non-multiplex PCR assay, each of the three virulence genes was amplified and detected in independent reactions. The specificity of these assays was evaluated using suspensions of STEC and other bacterial species lacking stx1, stx2 and eaeA. The multiplex assay detected all STEC harbouring any combination of three virulence genes. Three non-multiplex PCR reactions identified types of Shiga toxin genes carried by a STEC and identified STEC as either EHEC O157:H7 or non-O157:H7 STEC. Sensitivity limits of these assays in beef and faeces inoculated with EHEC O157:H7 were 5.8 to 580 cfu and 1.2 to 1200 cfu, respectively. These assays can be completed within 8-10 h when performed simultaneously or within 13 h if the multiplex assay is used as an initial screen for detecting STEC and the non-multiplex assay is used for subsequent detection of stx1 and stx2 of STEC and eaeA of EHEC O157:H7
Adhesins, Bacterial↗
Ultraviolet light-induced phase response curve for the locomotor activity rhythm of the field mouse Mus booduga.
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Animals↗
Precision of a mammalian circadian clock.
This paper reports study of day-to-day instability in the locomotor activity rhythm of the nocturnal field mouse Mus booduga. The free-running period (tau) of this rhythm was estimated in constant darkness in n = 347 adult male mice. The "onset" and "offset" of locomotor activity rhythm were used as phase markers of the circadian clock. The precision of the onset of locomotor activity was observed to be a non-linear function of tau, with maximal precision at tau close to 24 h. The precision of the offset of locomotor activity was found to increase with increasing tau. These results suggest that the homeostasis of tau is tighter when tau is close to 24 h.
Animals↗
Persistence of eclosion rhythm in Drosophila melanogaster after 600 generations in an aperiodic environment.
The ubiquity of circadian rhythms suggests that they have an intrinsic adaptive value (Ouyang et al. 1998; Ronneberg and Foster 1997). Some experiments have shown that organisms have enhanced longevity, development time or growth rates when maintained in environments whose periodicity closely matches their endogenous period (Aschoff et al. 1971; Highkin and Hanson 1954; Hillman 1956; Pittendrigh and Minis 1972; Went 1960). So far there has been no experimental evidence to show that circadian rhythms per se (i.e. periodicity itself, as opposed to phasing properties of a rhythm) confer a fitness advantage. We show that the circadian eclosion rhythm persists in a population of the fruitfly Drosophila melanogaster maintained in constant conditions of light, temperature, and humidity for over 600 generations. The results suggest that even in the absence of any environmental cycle there exists some intrinsic fitness value of circadian rhythms.
Adaptation, Physiological↗
Examination of tissue distribution of Helicobacter pylori within columnar-lined esophagus.
H. pylori may colonize columnar-lined esophagus, although an etiologic role in esophageal adenocarcinoma is unproven. H. pylori can adhere to intestinal metaplasia in the stomach. This study was designed to examine if H. pylori adheres to specialized intestinal metaplasia in columnar-lined esophagus. Esophageal biopsies from patients with columnar-lined esophagus were reviewed. Patients with only gastric metaplasia were excluded. Sections with specialized intestinal metaplasia in at least one third of at least one gland were recut, stained using the Giemsa stain, and reexamined by two independent pathologists using strict criteria for adherence by H. pylori. The 209 esophageal biopsies with adequate specialized intestinal metaplasia from 58 patients were examined: H. pylori was only seen on gastric metaplasia in three patients-and never on specialized intestinal metaplasia. Within the esophagus, H. pylori adheres only to gastric metaplasia, which is not considered premalignant for esophageal adenocarcinoma.
Adenocarcinoma↗
The effects on intragastric acidity of per-gastrostomy administration of an alkaline suspension of omeprazole.
BACKGROUND: It may be difficult to administer proton pump inhibitors via gastrostomy. Previous studies have examined the effect of intact proton pump inhibitor granules in orange juice. This study examined the effect of an alkaline suspension of omeprazole (simplified omeprazole suspension (SOS)) on 24-h intragastric acidity. METHODS: Six men with an established gastrostomy had a baseline 24-h intragastric pH study using methodology we have previously described. They then received 20 mg SOS o.d. for 7 days and had a repeat pH study at the end of this period. Four of the patients then received 20 mg SOS with 30 cc of liquid antacid (Mylanta) per gastrostomy o.d. for a further 7 days and then underwent a third pH study. RESULTS: SOS raised mean pH from 2.2 to 4.1. Intragastric pH was above 3, 4 and 5 for 35, 28 and 17% of the 24-h period at baseline, respectively; corresponding values after SOS were 63, 51 and 39%, respectively. Addition of liquid antacid to SOS did not further increase its pH-controlling effect. CONCLUSIONS: We found a statistically significant effect of o.d. SOS on intragastric pH when administered via gastrostomy. We found no additional benefit of administering SOS with liquid antacid.
Aged↗
Inhibition of apoptosis by ionomycin and zinc in peripheral blood mononuclear cells (PBMC) of leprosy patients.
PBMC from tuberculoid (BT/TT) and lepromatous leprosy (BL/LL) leprosy patients showed spontaneous apoptosis when cultured in the absence of mitogen for 24 h, which was inhibited by anti-tumour necrosis factor-alpha (TNF-alpha) antibodies. Apoptosis was also inhibited by ionomycin and zinc, which also increased IL-2 and decreased TNF-alpha production. The increase in IL-2 production suggests a mechanism whereby dietary supplements with zinc might alter the cell-mediated immunity response in leprosy patients.
Antibodies↗
Twice weekly 5 mg dexamethasone oral pulse in the treatment of extensive alopecia areata.
Thirty patients (20 males, 10 females) with widespread alopecia areata (25 extensive alopecia areata, 5 alopecia areata) for a mean period of 4.2 years were included in the study. All patients above 12 years were administered 5 mg dexamethasone oral pulse on two consecutive days every week. Three children (< 12 years) received 2.5 mg to 3.5 mg dexamethasone oral biweekly pulse. Patients who had received treatment for a minimum period of 12 weeks were evaluated for terminal hair growth. Complete to excellent (75-95%) hair growth was observed in 16 (63.3%) patients. Growth was good (50-74%) in 2 cases and poor (< 50%) in 3 (10%) cases. Six (20%) patients has no growth of terminal hair. Complete to excellent growth of hair was obtained after a mean period of 5.35 months (range 3-10 months). Relapse occurred in one case each after three and six months but hair regrew with re-treatment. Side effects of corticosteriods were frequent, seen in 8 (26.6%) patients, but were mild. In only one case, treatment had to be discontinued. We propose that twice weekly 5 mg dexamethasone oral pulse for six months may be considered as one of the modalities in the treatment of extensive long standing alopecia areata.
Administration, Oral↗
Macular lesions in leprosy: a clinical, bacteriological and histopathological study.
Among 150 untreated patients of leprosy, 19 had only macular lesions; three were of the indeterminate type, and eight each were of the tuberculoid and the borderline types, according to the Indian Association of Leprologists (IAL, 1981) classification. The clinical, bacteriological, and histopathological parameters of these 19 patients were studied both before and after six months of WHO Multi Drug Therapy (MDT/1982). A single macule was present in seven (36.84%) patients. In twelve (63.16%), two or more were seen. In eighteen (94.74%), one or more peripheral nerves were enlarged. The size of the macules varied from 5 to 15 cm, and there were no changes seen even after treatment. In most (94.74%) of the patients, the macules were hypopigmented. The surfaces were rough and dry in seven (36.84%) but smooth in the other twelve (63.16%). The margins were well defined in the seven (36.84%) patients with single macules but ill defined in the other twelve (63.16%). After six months of antileprosy treatment, the single macules showed some resolution. Slit skin smear examination was negative in all cases before and after treatment. Clinico-histopathological correlations were seen in only six (31.58%) patients; the clinical diagnoses were indeterminate and tuberculoid leprosy in three (15.79%) patients each. In the indeterminate group, the clinico-histopathological correlation was 100%; it was 37.50% in the tuberculoid group. There were no correlations between the clinical and histopathological parameters in thirteen (68.42%) cases. After six months of treatment, the histopathology became nonspecific in all patients. The lepromin test was positive in six (31.58%) patients; four were of the tuberculoid group and one each from the indeterminate and borderline leprosy groups. Hence, although macular lesions can be seen throughout the leprosy spectrum, it is difficult to correlate their clinical, bacteriological and histopathological parameters.
Adolescent↗
Evaluation of thyroid function in north Indians with alopecia areata: response to intravenous injection of 100 micrograms thyrotropin releasing hormone (TRH).
There is a lack of agreement on the overall prevalence of thyroid disease and thyroid function abnormalities in alopecia areata. Only one study is available from the Indian subcontinent. All patients with alopecia areata attending a dermatology outpatient clinic between 1983 and 1997 were screened for the presence of clinical thyroid disease. Sixty-two consecutive patients during the year 1994 were evaluated in detail for thyroid functions by measuring T3, T4, TSH levels and testing for antithyroid and antimicrosomal antibodies. Twenty-two patients randomly selected from the above-mentioned sixty two were studied for TSH response to intravenous injection of 100 micrograms TRH at -20, 0 and 20, 60, and 120 minutes after TRH injection. Thyroid disease was clinically evident in 16 (0.85%) of the 1700 patients with alopecia areata seen over the last fifteen years. All sixty-two patients evaluated for thyroid functions were clinically euthyroid. Seven (11.3%) out of these 62 patients had abnormal thyroid hormone levels. Antithyroid and antimicrosomal antibodies were found in five patients; all five had abnormalities in thyroid function. TSH response to TRH was suggestive of hypothyroidism in 4 (18%) of the 22 patients studied. Manifest thyroid disease is infrequently associated with alopecia areata. Abnormalities in thyroid functional status were more frequent; they were found in 7 (11.3%) out of 62 patients. TSH response to intravenous TRH was abnormal in an even higher proportion [4 (18%) out of 22 patients]. There was no apparent correlation with duration or type of alopecia areata.
Adolescent↗
Simplified lansoprazole suspension--a liquid formulation of lansoprazole--effectively suppresses intragastric acidity when administered through a gastrostomy.
OBJECTIVE: Lansoprazole suppresses intragastric acidity when given as nonencapsulated intact granules. Because the administration of granules via small-bore tubes may still be problematic, we studied the effect of a liquid formulation of lansoprazole obtained by suspending the contents of a standard 30-mg capsule in 10 cc of 8.4% NaHCO3. METHODS: Six men with an established gastrostomy had a baseline 24-h intragastric pH study. Through the gastrostomy, they then received 7 days of once-daily dosing with 30 mg lansoprazole as intact granules in orange juice. After a 7-day washout period, they then received 7 days of once-daily dosing with the liquid formulation. Intragastric pH monitoring was repeated after each dosing period. RESULTS: Baseline mean intragastric pH was 1.8 +/- 0.5 (SD). This increased to 4.5 +/- 0.5 with lansoprazole granules in orange juice, and to 5.1 +/- 1.1 after the liquid formulation. At baseline, intragastric pH was >3, 4, and 5 for 19.5%, 12.7%, and 8.1%, respectively, of the 24-h recording period. Corresponding values after lansoprazole granules in orange juice were 77.5%, 67%, and 49.6% (p < 0.01 for each comparison with baseline). After the liquid formulation, the corresponding values were 84%, 77.9%, and 65.9% respectively (p < 0.01 for each comparison with baseline; p > 0.05 for each comparison with lansoprazole granules in orange juice). CONCLUSIONS: A liquid formulation of lansoprazole suppressed intragastric acidity when given through a gastrostomy. The degree of suppression was comparable to that obtained with intact nonencapsulated granules in orange juice.
2-Pyridinylmethylsulfinylbenzimidazoles↗