Sensing beyond Senses: An Overview of Outstanding Strides in Architecting Nanopolymer-Enabled Sensors for Biomedical Applications

Nano-enabled sensing is an expanding interdisciplinary field of emerging science with dynamic multifunctional detecting capabilities, equipped with a wide range of multi-faceted nanomaterial having diverse dimensions and composition. They have proven to be highly robust, sensitive, and useful diagnostic tools ranging from advanced industrial processes to ordinary consumer products. As no single nanomaterial has proved to be unparalleled, recent years has witnessed a large number of nanomaterial-based sensing strategies for rapid detection and quantification of processes and substances with a high degree of reliability. Nano-furnished platforms, because of easy fabrication methods and chemical versatility, can serve as ideal sensing means through different transduction mechanisms. This article, through a unified experimental-theoretical approach, uses literature of recent years to introduce, evaluate, and analyze significant developments in the area of nanotechnology-aided sensors incorporating the various classes of nanomaterial. Addressing the broad interests, the work also summarizes the sensing mechanisms using schematic illustrations, attempts to integrate the performance of different categories of nanomaterials in the design of sensors, knowledge gaps, regulatory aspects, future research directions, and challenges of implementing such techniques in standalone devices. In view of a dependency of analysis and testing on sustained growth of sensor-supported platforms, this article inspires the scientific community for more attention in this field.

Histogram of States Based Assistive System for Speech Impairment Due to Neurological Disorders

Assistive speech technology is a challenging task because of the impaired nature of dysarthric speech, such as breathy voice, strained speech, distorted vowels, and consonants. Learning compact and discriminative embeddings for dysarthric speech utterances is essential for impaired speech recognition. We propose a Histogram of States (HoS)-based approach that uses Deep Neural Network-Hidden Markov Model (DNN-HMM) to learn word lattice-based compact and discriminative embeddings. Best state sequence chosen from word lattice is used to represent dysarthric speech utterance. A discriminative model-based classifier is then used to recognize these embeddings. The performance of the proposed approach is evaluated using three datasets, namely 15 acoustically similar words, 100-common words datasets of the UA-SPEECH database, and a 50-words dataset of the TORGO database. The proposed HoS-based approach performs significantly better than the traditional Hidden Markov Model and DNN-HMM-based approaches for all three datasets. The discriminative ability and the compactness of the proposed HoS-based embeddings lead to the best accuracy of impaired speech recognition.

Self-perceived halitosis and oral hygiene habits among undergraduate dental students

Background:

Halitosis or oral malodor is characterized by unpleasant odor arising from the oral cavity. The prevalence of halitosis however is not studied extensively. The aim of this study was to evaluate the self perception of oral malodor and oral hygiene habits amongst dental students.

Materials and Methods:

A structured questionnaire consisting of ten questions was administered to 285 undergraduate students of Madha Dental College and Hospital. The questionnaire was designed to evaluate the self perception of halitosis, oral hygiene aids used, presence of dental caries, gingival bleeding, and dryness of mouth.

Results:

Of the 285 students, 259 students completed the questionnaire. The response rate was 90%, with male response rate being 85.7% and female 95.8%. Self-perceived halitosis was reported by 44.1% males and 45.32% females. The difference in reporting self-perception of halitosis between females and males was found to be statistically significant (P < 0.05). Significant difference was found for use of mouth wash, presence of carious teeth, bleeding gums, and use of tongue cleaners between females and males (P < 0.05).

Conclusion:

The results of this study indicate higher prevalence of halitosis among this population consisting of dental students. The awareness of halitosis was also higher among this population. The awareness of halitosis as an individual entity should be promoted to the general population and the therapeutic measures should be made available to all.

Isolation, Purification, and Characterization of Fungal Laccase from Pleurotus sp

Laccases are blue copper oxidases (E.C. 1.10.3.2 benzenediol: oxygen oxidoreductase) that catalyze the one-electron oxidation of phenolics, aromatic amines, and other electron-rich substrates with the concomitant reduction of O₂ to H₂O. They are currently seen as highly interesting industrial enzymes because of their broad substrate specificity. A positive strain was isolated and characterized as nonspore forming Basidiomycetes Pleurotus sp. Laccase activity was determined using ABTS as substrate. Laccase was purified by ionexchange and gel filtration chromatography. The purified laccase was a monomer showed a molecular mass of 40 ± 1 kDa as estimated by SDS-PAGE and a 72-fold purification with a 22% yield. The optimal pH and temperature were 4.5 and 65^°C, respectively. The K_m and V_max values are 250 (mM) and 0.33 (μmol/min), respectively, for ABTS as substrate. Metal ions like CuSO₄, BaCl₂, MgCl₂, FeCl₂, ZnCl₂ have no effect on purified laccase whereas HgCl₂ and MnCl₂ moderately decrease enzyme activity. SDS and sodium azide inhibited enzyme activity, whereas Urea, PCMB, DTT, and mercaptoethanol have no effect on enzyme activity. The isolated laccase can be used in development of biosensor for detecting the phenolic compounds from the effluents of paper industries.

Dose-response relationship between alcohol consumption before and during pregnancy and the risks of low birthweight, preterm birth and small for gestational age (SGA)-a systematic review and meta-analyses

BACKGROUND

Descriptions of the effects of moderate alcohol consumption during pregnancy on adverse pregnancy outcomes have been inconsistent.

OBJECTIVE

To review systematically and perform meta-analyses on the effect of maternal alcohol exposure on the risk of low birthweight, preterm birth and small for gestational age (SGA).

SEARCH STRATEGY

Using Medical Subject Headings, a literature search of MEDLINE, EMBASE, CINAHL, CABS, WHOlist, SIGLE, ETOH, and Web of Science between 1 January 1980 and 1 August 2009 was performed followed by manual searches.

SELECTION CRITERIA

Case-control or cohort studies were assessed for quality (STROBE), 36 available studies were included.

DATA COLLECTION AND ANALYSIS

Two reviewers independently extracted the information on low birthweight, preterm birth and SGA using a standardised protocol. Meta-analyses on dose-response relationships were performed using linear as well as first-order and second-order fractional polynomial regressions to estimate best fitting curves to the data.

MAIN RESULTS

Compared with abstainers, the overall dose-response relationships for low birthweight and SGA showed no effect up to 10 g pure alcohol/day (an average of about 1 drink/day) and preterm birth showed no effect up to 18 g pure alcohol/day (an average of 1.5 drinks/day); thereafter, the relationship showed a monotonically increasing risk for increasing maternal alcohol consumption. Moderate consumption during pre-pregnancy was associated with reduced risks for all outcomes.

CONCLUSIONS

Dose-response relationship indicates that heavy alcohol consumption during pregnancy increases the risks of all three outcomes whereas light to moderate alcohol consumption shows no effect. Preventive measures during antenatal consultations should be initiated.

Development of new cytoplasmic-genetic male-sterile lines in pigeonpea from crosses between Cajanus cajan (L.) Millsp.and C. scarabaeoides (L.) Thouars

Exploitation of hybrid vigour is quite possible in cross-pollinated crops. However, pigeonpea is a grain legume crop with a moderate level of cross-pollination (20-70%), which is mainly aided by insect pollinators. As a first step, hybrids based on genetic male sterility (GMS) were developed in pigeonpea, but the hybrid seed production technique is not farmer-friendly, because in the hybrid seed production plot 50% of the population, which are male-fertile in the female rows, have to be eliminated in time before contamination. This requires skilled labour and is a time-consuming process, which increases the cost of hybrid seed production. Therefore, the objective of this study was to develop cytoplasmic-genetic male-sterile (CGMS) lines in pigeonpea through wide hybridization, which would be very suitable for hybrid seed production. Two CGMS lines, viz. CORG 990052 A and CORG 990047, were developed by interspecific hybridization of Cajanus cajan and C. scarabaeoides. Restorers were identified and three CGMS-based pigeonpea hybrids were developed. The hybrid COPH 3 is found to be promising in Tamil Nadu State, India.

Developmental and Behavioral Consequences of Prenatal Fluoxetine

BACKGROUND

Fluoxetine, a selective serotonin reuptake inhibitor, is the most commonly prescribed antidepressant drug for pregnant women. Studies regarding the teratogenic effect of fluoxetine on human and animal models are mainly concerned with structural malformation (congenital anomalies).

AIM

Hence, the present study was planned to evaluate the postnatal behavioral effects of fluoxetine on albino rats.

METHODS

Three groups of female rats received either distilled water or doses of fluoxetine 8 and 12 mg/kg orally from the 6th to the 20th day of pregnancy. Weaning of the pups was done on the 21st day followed by a battery of behavioral tests to assess for any behavioral effect. The tests included negative geotaxis, open field exploration, rota-rod test, elevated plus maze and passive avoidance test.

RESULTS

In the present study there was no change in the gestational length of pregnancy, no premature birth or miscarriage during pregnancy. A high dose of in utero fluoxetine resulted in a decrease in birth weight of the offspring and also reduced weight gain during the preweaning period. No major congenital abnormalities were observed in the offspring exposed to fluoxetine. Prenatal fluoxetine exposure at high dose caused an initial transient delay in motor development and this poor motor activity was transient and not permanent. However, prenatal exposure to fluoxetine at a higher dose showed a favorable effect on learning and memory in water maze and passive avoidance tests.

CONCLUSIONS

From the present study, it may be concluded that prenatal fluoxetine causes a transient delay in motor development but does not adversely affect the postnatal behavioral consequences.

Activity of Wedelia calendulacea Less. in post-menopausal osteoporosis

Wedelia calendulacea Less., a perennial herb containing isoflavanoids, is used in liver disorders, uterine hemorrhage and menorrhagia. Osteoporosis in women occurs mainly due to estrogen deficiency following menopause. Studies indicate that isoflavones are estrogenic enough to promote bone formation. Our study was aimed to investigate the antiosteoporotic effect of the ethanol extract of W. calendulacea in the ovariectomized rat model of osteoporosis, at two different dose levels of 500 and 750 mg/kg/body wt. day. The findings, assessed on the basis of biomechanical and biochemical parameters, showed that the ethanol extract of the plant had a definite protective effect. This was further supported by the histopathological studies. Phytochemical investigation revealed the presence of isoflavones and wedelolactone, which are known to act as phytoestrogens and may be responsible for the antiosteoporotic activity.

Effect of Cassia auriculata Linn. root extract on cisplatin and gentamicin-induced renal injury

The ethanol extract of the roots of Cassia auriculata was studied for its nephroprotective activity in cisplatin- and gentamicin-induced renal injury in male albino rats. In the cisplatin model, the extract at doses of 300 and 600 mg/kg body wt. reduced elevated blood urea and serum creatinine and normalized the histopathological changes in the curative regimen. In the gentamicin model, the ethanol extract at a dose of 600 mg/kg body wt. reduced blood urea and serum creatinine effectively in both the curative and the preventive regimen. The extract had a marked nitric oxide free-radical-scavenging effect. The findings suggest that the probable mechanism of nephroprotection by C. auriculata against cisplatin- and gentamicin-induced renal injury could be due to its antioxidant and free-radical-scavenging property.

Effect of Aerva lanata on cisplatin and gentamicin models of acute renal failure

The ethanol extract of the entire plant of Aerva lanata was studied for its nephroprotective activity in cisplatin- and gentamicin-induced acute renal injury in albino rats of either sex. In the curative regimen, the extract at dose levels of 75, 150 and 300 mg/kg showed dose-dependent reduction in the elevated blood urea and serum creatinine and normalized the histopathological changes in the curative regimen. In the gentamicin model the rats in the preventive regimen also showed good response to the ethanol extract at 300 mg/kg. The findings suggest that the ethanol extract of Aerva lanata possesses marked nephroprotective activity with minimal toxicity and could offer a promising role in the treatment of acute renal injury caused by nephrotoxins like cisplatin and gentamicin.

Antiosteoporotic effect of ethanol extract of Cissus quadrangularis Linn. on ovariectomized rat

Ethanol extract of Cissus quadrangularis was evaluated for its anti-osteoporotic activity in ovariectomized rat model of osteoporosis at two different dose levels of 500 and 750 mg/kg per day. Healthy female albino rats were divided into five groups of six animals each. First group was sham operated and served as control. All the remaining groups were ovariectomized. Group 2 was fed with equivolume of saline and served as ovariectomized control. Groups 3-5 were orally treated with Raloxifen (5.4 mg/kg) and ethanol extract of Cissus quadrangularis (500 and 750 mg/kg), respectively. The findings assessed on the basis of biomechanical, biochemical and histopathological parameters showed that the ethanol extract of the plant had a definite antiosteoporotic effect.

The gastroprotective activity of the ethanol extract of Ageratum conyzoides

The ethanol extract of Ageratum conyzoides was evaluated for gastroprotection in rats using the Ibuprofen, ethanol and cold restraint stress ulcer models. Efficacy was assessed by determination of mean ulcer size, ulcer number and ulcer index. Oral administration of the ethanol extract at dose levels of 500 and 750 mg/kg significantly protected gastric lesions by 80.59 and 89.33%, respectively, as compared to Misoprostol (74.43%) in the Ibuprofen model; by 97.09 and 99.24%, respectively, in the cold stress model as compared to Famotidine (77.86 and 92.71%) and by 86.58 and 92.29%, respectively, in the alcohol model. The findings suggest that the significant gastroprotective activity could be mediated by its antioxidant activity, Ca(2+) channel blocking and antiserotogenic properties.

Protective effect of Pongamia pinnata flowers against cisplatin and gentamicin induced nephrotoxicity in rats

Ethanolic extract of flowers of Pongamia pinnata was studied for its protective effect against cisplatin and gentamicin induced renal injury in rats. When the extract (300 & 600 mg kg(-1)) was administered orally for 10 days following cisplatin (5 mg kg(-1) i.p.) on day 5, toxicity of cisplatin, as measured by loss of body weight, elevated blood urea and serum creatinine declined significantly. Similarly in gentamicin (40 mg kg(-1) s.c.) induced renal injury, the extract (600 mg kg(-1)) normalized the raised blood urea and serum creatinine levels. Reversal of cisplatin and gentamicin renal cell damage as induced by tubular necrosis ie, marked congestion of the glomeruli with glomerular atrophy, degeneration of tubular epithelial cells with casts in the tubular lumen and infiltration of inflammatory cells in the interstitium was confirmed on histopathological examination. In the preventive regimen, co-administration of the extract with gentamicin significantly prevented the renal injury both functionally and histologically. Ethanolic extract of flowers had a marked nitric oxide free radical scavenging effect, suggesting an antioxidative property. Two flavonoids, known for their antioxidant activity viz. kaempferol and 3, 5, 6, 7, 8-pentamethoxy flavone were isolated from the extract. The results suggested that the flowers of Pongamia pinnata had a protective effect against cisplatin and gentamicin induced renal injury through antioxidant property.

The role of parathyroid ultrasonography in the management of primary hyperparathyroidism

High-resolution, real-time sonography can be used to assess the size and location of the parathyroid glands. The authors review the types of information provided by sonography and outline the ways in which it contributes to the management of primary hyperparathyroidism. Sonography usually can differentiate parathyroid adenoma from hyperplasia. In milder cases, with less parathyroid enlargement, this differentiation is difficult but can be facilitated by determining three dimensions for each gland. Preoperative knowledge of the presumptive location of an adenoma is most useful when the strategy of unilateral neck exploration is to be used because it will allow the exploration always to begin on the correct side. Sonographic evidence of hyperplasia should trigger a preoperative search for multiple endocrine neoplasia and will alert the surgeon that a bilateral neck exploration and thymectomy will be needed. A more universal benefit is the ability to predict or exclude intrathyroidal and subcapsular parathyroid tumors, thus guiding the decision for thyroid versus thymic exploration in the event of a missing abnormal gland. Sonography often fails to visualize parathyroid tumors in an ectopic position away from the thyroid bed. Such tumors, however, may be anticipated when the sonogram shows only three enlarged glands in cases of hyperplasia, or only three glands of normal size in a patient with strong biochemical evidence of hyperparathyroidism. Because it is noninvasive and inexpensive and can provide a wealth of information, the authors have adopted sonography as a routine preoperative procedure for primary hyperparathyroidism.

Lithium treatment increases intact and midregion parathyroid hormone and parathyroid volume

Lithium carbonate is known to alter calcium metabolism by lowering urinary calcium excretion and increasing serum calcium concentrations. Several investigators have reported increases in serum immunoreactive PTH (iPTH) values after a few weeks or months of lithium treatment, and several cases of primary hyperparathyroidism developing during lithium treatment have been reported. To determine whether the increases in serum iPTH might be the result of increased renal retention of inactive PTH fragments rather than stimulation of parathyroid function, we measured plasma intact PTH by immunoradiometric assay and estimated parathyroid size by ultrasonography in men who had received short term (less than 6 months) or long term (greater than 3 yr) lithium treatment and in normal subjects. Serum ionized calcium was higher by 0.03-0.04 mmol/L in subjects treated short term (mean, 1.7 months) with lithium than in normal subjects, but plasma intact PTH and serum midregion iPTH values were not different. The absence of a reciprocal decrease in PTH values is compatible with a lithium-induced shift in the set-point for the inhibition of PTH secretion by calcium toward a higher calcium value. Both plasma intact PTH and serum midregion PTH values were higher in subjects during longer term (mean, 103 months) lithium treatment, and estimated parathyroid volume was 3-fold higher. Serum phosphate was lower, and serum chloride and plasma 1,25-dihydroxy-vitamin D values were higher in those treated with lithium long term, probably from the biological action of the increased PTH. We conclude that long term lithium treatment increases circulating biologically active PTH and causes parathyroid enlargement. Whether this chronic stimulus to parathyroid growth might lead to adenoma formation in certain susceptible individuals and whether a PTH-induced increase in skeletal remodelling occurs that might hasten the appearance of osteopenia remain to be determined.

The Nager syndrome

The Nager syndrome was identified in a newborn infant and in a subsequent sib by prenatal ultrasonography. This report documents an autosomal recessive pattern of inheritance for this disorder.

Familial cystic parathyroid adenomatosis

Although the commonest familial form of primary hyperparathyroidism is parathyroid hyperplasia, a few families have manifested parathyroid adenomas. We describe a family in which four members developed cystic parathyroid adenomas. Although calcium levels returned to normal after resection of the adenoma, a second adenoma would often develop several years later (we have termed this temporal sequence adenomatosis). Each adenoma had a cystic histologic appearance, and three of four normal-sized parathyroid glands also contained many cysts. No other endocrine tumors have appeared, but in three patients the hyperparathyroidism was complicated by fibrous maxillary or mandibular tumors that resembled ossifying fibromas rather than the brown tumors generally found in patients with hyperparathyroidism. Each patient with an adenoma was hypercalciuric, but two were obligate carriers of hypocalciuric hypercalcemia. This familial occurrence of the rare cystic parathyroid adenoma suggests the presence of a distinct hereditary syndrome. The genetic basis may be the simultaneous inheritance of familial hypocalciuric hypercalcemia and another trait that may increase the urinary excretion of calcium.

Measurement of breast volume by ultrasound during normal menstrual cycles and with oral contraceptive use

The volume of the human breast was measured by ultrasonographic methods with good reliability and reproducibility. Variations in breast volume of up to 36% were encountered with weekly measurements during the course of seven normal menstrual cycles. Oral contraceptives containing 35 to 50 micrograms ethynyl estradiol and amounts of norethindrone varying over a range of 0.4 to 2.5 mg/day and used for six cycles did not produce dose-related changes in breast volume as compared with untreated control subjects, but the sensitivity of the experiment was reduced by notable individual variation and relatively small sample sizes.

Sonographic diagnosis and classification of anomalies of the female genital tract

A retrospective study of 68 female patients with sonographic diagnoses of genital tract anomalies was done. Corroboration by hysterosalpingography and/or surgery was available in 47 cases (69 per cent) and by visualization of two cervices on physical examination in three cases (4 per cent). Scan results are categorized as diagnostic, confirmatory, and incorrect. The 50 patients were placed in the following proposed categories: segmental mullerian agenesis (four cases); "peculiar appearing" uterus (three cases); uterus didelphys (19 cases); bicornuate and septate uterus (22 cases); obstructed lower with normal upper genital tract (two cases).

Ultrasound evaluation of female genital tract anomalies: a review of 64 cases

Sixty-four patients with an ultrasound diagnosis of an anomaly of the female genital tract were studied retrospectively to determine the accuracy and usefulness of sonographic examination of these anomalies in the pregnant (64%) and the nonpregnant (36%) patient. Ultrasound diagnoses in 46 patients with follow-up included: (1) bicornuate/septate uterus in 21 cases, (2) uterus didelphys in 18 cases, (3) cervical and vaginal atresia in three cases, (4) obstructed lower but normal upper genital tract in two cases, and (5) abnormal-appearing uterus in two cases. Ultrasound diagnosis was compared with hysterosalpingographic and/or surgical findings in 43 patients and with physical examination in three patients. Scan results were classified as diagnostic in 26%, confirmatory in 63%, and incorrect in 11%. Ultrasound is a reliable clinically useful method of studying genital tract anomalies in gynecologic patients.

The correlation of pelvic ultrasound and laparoscopy in the diagnosis and management of gynecologic disorders

Cases were reviewed in which both laparoscopy and ultrasound were performed for diagnostic purposes at the Ben Taub General Hospital, Houston, Texas, from January 1976 through May 1977. Thirty patients were found to have undergone both procedures. The most common reason (13 cases) was the presence of an adnexal mass. The findings from both techniques agreed in 20 cases, for a positive correlation of 66.7%. Different diagnoses were found in 10 cases, for a negative correlation of 33.3%. The major cause of the discrepancy was the presence of pelvic adhesive disease, not diagnosed by ultrasound but observed via laparoscopy. When the ultrasound findings were reported as "normal," all were confirmed at laparoscopy. Eight laparotomies were performed, and in each case the laparoscopic findings were confirmed.

Prenatal diagnosis of recurrence of Saldino-Noonan dwarfism

The occurrence in a family of three spontaneous abortions and two siblings with Saldino-Noonan dwarfism supports an autosomal recessive etiology and raises the possibility of lethality early in utero. No long bones were visualized in radiographs at 19 weeks' gestation in the second affected pregnancy. highlighting the difficulties of distinguishing technical limitations from fetal anatomic abnormalities. Ultrasound studies demonstrated oligohydramnios. Radiologic prenatal diagnosis can rule out this condition prior to 20 to 24 weeks' gestation and affected fetuses can be suspected if not proved by radiographs and ultrasound examination.

Ultrasonography in obstructive jaundice

The usefulness of ultrasonography in the preliminary evaluation of obstructive jaundice is described in 35 consecutive patients with icterus. Diagnosis was substantiated by laparotomy, autopsy, or liver biopsy. In 23 patients with dilated bile ducts at ultrasonography, obstruction by tumor, stone, or stricture was proven operatively. Obstructive jaundice was differentiated from hepatocellular jaundice in 86% of cases; the site of obstruction was noted to be correct in 85%. The accuracy in the diagnosis of obstructive jaundice was 100% in patients with moderate or severe icterus.