Constraints on Cosmic Strings Using Data from the Third Advanced LIGO-Virgo Observing Run

We search for gravitational-wave signals produced by cosmic strings in the Advanced LIGO and Virgo full O3 dataset. Search results are presented for gravitational waves produced by cosmic string loop features such as cusps, kinks, and, for the first time, kink-kink collisions. A template-based search for short-duration transient signals does not yield a detection. We also use the stochastic gravitational-wave background energy density upper limits derived from the O3 data to constrain the cosmic string tension Gμ as a function of the number of kinks, or the number of cusps, for two cosmic string loop distribution models. Additionally, we develop and test a third model that interpolates between these two models. Our results improve upon the previous LIGO-Virgo constraints on Gμ by 1 to 2 orders of magnitude depending on the model that is tested. In particular, for the one-loop distribution model, we set the most competitive constraints to date: Gμ≲4×10^{-15}. In the case of cosmic strings formed at the end of inflation in the context of grand unified theories, these results challenge simple inflationary models.

Constraints on Cosmic Strings Using Data from the Third Advanced LIGO-Virgo Observing Run

We search for gravitational-wave signals produced by cosmic strings in the Advanced LIGO and Virgo full O3 dataset. Search results are presented for gravitational waves produced by cosmic string loop features such as cusps, kinks, and, for the first time, kink-kink collisions. A template-based search for short-duration transient signals does not yield a detection. We also use the stochastic gravitational-wave background energy density upper limits derived from the O3 data to constrain the cosmic string tension Gμ as a function of the number of kinks, or the number of cusps, for two cosmic string loop distribution models. Additionally, we develop and test a third model that interpolates between these two models. Our results improve upon the previous LIGO-Virgo constraints on Gμ by 1 to 2 orders of magnitude depending on the model that is tested. In particular, for the one-loop distribution model, we set the most competitive constraints to date: Gμ≲4×10^{-15}. In the case of cosmic strings formed at the end of inflation in the context of grand unified theories, these results challenge simple inflationary models.

GW190521: A Binary Black Hole Merger with a Total Mass of 150 M_{⊙}

On May 21, 2019 at 03:02:29 UTC Advanced LIGO and Advanced Virgo observed a short duration gravitational-wave signal, GW190521, with a three-detector network signal-to-noise ratio of 14.7, and an estimated false-alarm rate of 1 in 4900 yr using a search sensitive to generic transients. If GW190521 is from a quasicircular binary inspiral, then the detected signal is consistent with the merger of two black holes with masses of 85_{-14}^{+21}  M_{⊙} and 66_{-18}^{+17}  M_{⊙} (90% credible intervals). We infer that the primary black hole mass lies within the gap produced by (pulsational) pair-instability supernova processes, with only a 0.32% probability of being below 65  M_{⊙}. We calculate the mass of the remnant to be 142_{-16}^{+28}  M_{⊙}, which can be considered an intermediate mass black hole (IMBH). The luminosity distance of the source is 5.3_{-2.6}^{+2.4}  Gpc, corresponding to a redshift of 0.82_{-0.34}^{+0.28}. The inferred rate of mergers similar to GW190521 is 0.13_{-0.11}^{+0.30}  Gpc^{-3} yr^{-1}.

Dental extraction in a patient with undiagnosed Von Willebrand's Disease: a case report

Dental extractions are a common part of general dental practice. While dentists routinely screen for medical contraindications during the preoperative assessment, undiagnosed coagulopathies have the potential to severely complicate a seemingly routine extraction. We report a case of surgical removal of a mandibular third molar in a patient with undiagnosed Von Willebrand Disease.

Search for Subsolar Mass Ultracompact Binaries in Advanced LIGO's Second Observing Run

We present a search for subsolar mass ultracompact objects in data obtained during Advanced LIGO's second observing run. In contrast to a previous search of Advanced LIGO data from the first observing run, this search includes the effects of component spin on the gravitational waveform. We identify no viable gravitational-wave candidates consistent with subsolar mass ultracompact binaries with at least one component between 0.2  M_{⊙}-1.0  M_{⊙}. We use the null result to constrain the binary merger rate of (0.2  M_{⊙}, 0.2  M_{⊙}) binaries to be less than 3.7×10^{5}  Gpc^{-3} yr^{-1} and the binary merger rate of (1.0  M_{⊙}, 1.0  M_{⊙}) binaries to be less than 5.2×10^{3}  Gpc^{-3} yr^{-1}. Subsolar mass ultracompact objects are not expected to form via known stellar evolution channels, though it has been suggested that primordial density fluctuations or particle dark matter with cooling mechanisms and/or nuclear interactions could form black holes with subsolar masses. Assuming a particular primordial black hole (PBH) formation model, we constrain a population of merging 0.2  M_{⊙} black holes to account for less than 16% of the dark matter density and a population of merging 1.0  M_{⊙} black holes to account for less than 2% of the dark matter density. We discuss how constraints on the merger rate and dark matter fraction may be extended to arbitrary black hole population models that predict subsolar mass binaries.

Trend and variability of atmospheric ozone over middle Indo-Gangetic Plain: impacts of seasonality and precursor gases

Ozone dynamics in two urban background atmospheres over middle Indo-Gangetic Plain (IGP) were studied in two contexts: total columnar and ground-level ozone. In terms of total columnar ozone (TCO), emphases were made to compare satellite-based retrieval with ground-based observation and existing trend in decadal and seasonal variation was also identified. Both satellite-retrieved (Aura Ozone Monitoring Instrument-Differential Optical Absorption Spectroscopy (OMI-DOAS)) and ground-based observations (IMD-O₃) revealed satisfying agreement with OMI-DOAS observation over predicting TCO with a positive bias of 7.24 % under all-sky conditions. Minor variation between daily daytime (r = 0.54; R ² = 29 %; n = 275) and satellite overpass time-averaged TCO (r = 0.58; R ² = 34 %; n = 208) was also recognized. A consistent and clear seasonal trend in columnar ozone (2005-2015) was noted with summertime (March-June) maxima (Varanasi, 290.9 ± 8.8; Lucknow, 295.6 ± 9.5 DU) and wintertime (December-February) minima (Varanasi, 257.4 ± 10.1; Lucknow, 258.8 ± 8.8 DU). Seasonal trend decomposition based on locally weighted regression smoothing technique identified marginally decreasing trend (Varanasi, 0.0084; Lucknow, 0.0096 DU year^-1) especially due to reduction in monsoon time minima and summertime maxima. In continuation to TCO, variation in ground-level ozone in terms of seasonality and precursor gases were also analysed from September 2014 to August 2015. Both stations registered similar pattern of variation with Lucknow representing slightly higher annual mean (44.3 ± 30.6; range, 1.5-309.1 μg/m³) over Varanasi (38.5 ± 17.7; range, 4.9-104.2 μg/m³). Variation in ground-level ozone was further explained in terms water vapour, atmospheric boundary layer height and solar radiation. Ambient water vapour content was found to associate negatively (r = -0.28, n = 284) with ground-level ozone with considerable seasonal variation in Varanasi. Implication of solar radiation on formation of ground-level ozone was overall positive (Varanasi, 0.60; Lucknow, 0.26), while season-specific association was recorded in case of atmospheric boundary layer.

Role of demographic and job-related variables in determining work-related quality of life of hospital employees

BACKGROUND

Considering a huge working population in health sector faced with stressful work life, limited autonomy in work and declining work contentment calls for an overemphasis on evaluating and monitoring their satisfaction associated with work-related quality of life (WRQoL). This study evaluates WRQoL of hospital employees and validates the bilingual (English and Marathi) version of WRQoL scale.

METHODS

The study was conducted during March-April'2014 on employees of a corporate hospital of Pune, India after ethical approval and informed consent from employees. The bilingual WRQoL scale has been tested for reliability and validity, and WRQoL scores have been reported.

RESULTS

A total of 132 hospital employees (mean age 31 [±8] years, 55% males) who participated in the study reported overall moderate WRQoL scores. The scale showed high internal consistency (Cronbach's alpha = 0.82, P < 0.0001) and moderate to high validity. WRQoL did not significantly vary across marital status, family size, and gender. "Stress at work" score of WRQoL increased with age of employees. Higher work experience, employment at higher positions and those working in clinical and diagnostic departments reported a higher WRQoL.

CONCLUSION

WRQoL scale is a reliable and valid instrument. Better WRQoL in employees placed in higher organizational positions indicates a need for focused measures to enhance WRQoL of employees in lower hierarchical levels, especially in control at work and home life interface domains. WRQoL needs regular monitoring for employees in lower positions and aging employees.

Shift work--problems and its impact on female nurses in Udaipur, Rajasthan India

Abstract : There is good evidence that shift work has negative effects on workers health, safety and performance. It is quite appropriate that attention is paid to this very important feature of socio-technical systems, which may adversely affect mental and physical health, social life and safety of shift workers. Research into the impact of shift work on professionals has consistently identified a range of negative outcomes in physical, psychological, and social domains (Akerstedt, 1988; Costa, Lievore, Casaletti, Gaffuri, & Folkard, 1989; Kogi, 2005; Paley & Tepas, 1994). Hospitals, the biggest employer in the health care field, employ more night shift workers than any other industry. It can therefore be inferred that in medical domain high percentage of workforce may be affected by problems related to shift work. Thus the present study will provide knowledge base for the problems faced by the female nurses. The present study was undertaken with an objective of getting an insight into the problems faced by female nurses in shift work. . It was found that the female nurses in India worked on roaster pattern of change in shift every seven days. They did not have a say in the change of duties, it could only be done on mutual grounds. Partners of younger group did not much adjust to their shift pattern this created stress among the nurses.The results showed that the female nurses in both the age groups i.e. 30-45 years and 45-60 years faced many problems related to health and well being, fatigue, social and domestic situations. They could not give much time to their children in particular. Travelling in nights was risky for them. Common problem was the insufficient sleep during night shifts. The nurses had to cater to the needs of the family, children in particular along with the adjustments to be made due to shift work. They had to sometimes do the night duties and attend social functions as a part of their duty. Children and husband in some cases did not cooperate this lead to frustration. When asked as to whether they would could shift job if they get regular one more than 50 % said yes this means that there need to be come training and intervention for the shift workers and their family so that the problems faced and their impact on personal health of the female nurses could be reduced.

Structure-activity relationships of glutamate carboxypeptidase II (GCPII) inhibitors

Glutamate carboxypeptidase II (GCPII, EC 3.4.17.21) is a zinc metallopeptidase that hydrolyzes N-acetylaspartylglutamate (NAAG) into N-acetylaspartate (NAA) and glutamate in the nervous system. Inhibition of GCPII has the potential to reduce extracellular glutamate and represents an opportune target for treating neurological disorders in which excess glutamate is considered pathogenic. Furthermore, GCPII was found to be identical to a tumor marker, prostate-specific membrane antigen (PSMA), and has drawn significant interest as a diagnostic and/or therapeutic target in oncology. Over the past 15 years, tremendous efforts have been made in the discovery of potent GCPII inhibitors, particularly those with phosphorus-, urea- and thiol-based zinc binding groups. In addition, significant progress has been made in understanding the three-dimensional structural characteristics of GCPII in complex with various ligands. The purpose of this review article is to analyze the structure-activity relationships (SAR) of GCPII inhibitors reported to date, which are classified on the basis of their zinc-binding group. SAR and crystallographic data are evaluated in detail for each of these series to highlight the future challenges and opportunities to identify clinically viable GCPII inhibitors.

Steroid binding at sigma receptors: CNS and immunological implications

The sigma receptor has been suggested to be the mediator of the psychomimetic effects induced by certain benzomorphan opioids and phencyclidine. Potent sigma receptor ligands include haloperidol and other 'atypical' potential antipsychotic drugs. The sigma receptor is found in the central nervous system and also in the immune and endocrine systems. Gonadal and adrenal steroids such as progesterone, testosterone, deoxycorticosterone and corticosterone were found to be competitive inhibitors of binding of the sigma receptor ligand [3H] d-SKF-10,047. The sigma receptor is not the traditionally recognized cytosolic progesterone receptor and is found in crude membrane fractions. Results from molecular modelling using geometric fitting and electrostatic potential calculations suggested that the molecular skeleton of steroid hormones shares common features with prototypic sigma ligands such as d-SKF-10,047 and that the oxygen of the C-20 carbonyl group on these steroids may represent a critical 'pharmacophore' for their interactions with sigma receptors. Comparison of the affinities of steroids at sigma receptors with their efficacies is an anti-inflammatory test yielded a striking qualitative correlation. Taken Taken together these results suggest that sigma receptors may mediate certain aspects of steroid-induced mental disturbances and alterations in immune function.

A unilateral teratoid Wilms' tumor with raised serum alpha-fetoprotein level

Teratoid Wilms' tumor with raised serum alpha-fetoprotein level is an unusual type of tumor. We, here, describe a twelve month old boy presenting with lumbar mass. Clinical features, radiological findings, gross examination, and histomorphological features are studied, and various differential diagnoses like Wilms' tumor with heterologous elements, intrarenal teratoma and metastatic germ cell tumor are taken into consideration.

Primary gastrointestinal lymphoma--a clinicopathologic study

Gastrointestinal tract is the most common site for the development ofextra nodal lymphoma. This study was done to analyze clinical and pathological features as well as the treatment outcome of this disease. We carried out analysis of25 cases of primary gastrointestinal (GI) lymphomas during period from March 2001 to February 2003 at Gujarat Cancer & Research Institute. Out of 25 cases of primary GI lymphoma, nine cases of gastric lymphoma, nine cases of small intestinal lymphoma and seven cases of large intestinal lymphoma were identified. A male to female ratio of 2.6:1 was observed. Peak incidence was observed infirst and second decades of life (range 4-63 years). Abdominal pain and abdominal lump were the two most common presenting symptoms. Diffuse large B-cell type and Burkitt's lymphoma were the most common histologic variants, accounting for equal proportions (36% each). All the patients were treated with either surgery alone or in combination of surgery, chemotherapy and radiotherapy depending on the site, stage and histology. Anti H-pylori kit was used in early stage GI maltomas. 18 cases of GI lymphoma were evaluable, and out of these, 66.6% (11 cases) attained complete remission with a median follow up time of 12 months. The disease free survival was 50% (9 cases), and the overall survival was 72.2% (13 cases). In conclusion, although there are considerable therapeutic controversies, surgery with adjuvant chemotherapy and radiotherapy yield good survival. Clinical and histopathologic characteristics and prognosis of our cases with primary gastrointestinal lymphoma were usually similar to the cases in western countries with some differences in the incidence and histologic subtypes.

Brain metastasis from cervical carcinoma

The aim of this study was to describe the features of patients with brain metastasis from cervical cancer. Twelve patients with brain metastasis from cervical cancer were identified. Information regarding symptoms, treatment, and survival was analyzed. The incidence of brain metastasis in our population was 0.77%. Median patient age at initial diagnosis of cervical cancer was 43.5 years (range 29-57 years) compared with 44.5 years (range 31-58 years) at identification of brain metastasis. Six patients had FIGO stage IB disease; three had stage IIB disease; and one each had stage IIIA, IIIB, and IVB disease. The median interval from diagnosis of cervical cancer to identification of brain metastasis was 17.5 months (range 1.1-96.1 months). All but one patient presented with neurologic symptoms. Eight patients received whole-brain irradiation and steroids, three received steroids alone, and one underwent surgery, followed by irradiation. All the patients who received whole-brain irradiation experienced improvement in their symptoms. Median survival from diagnosis of brain metastasis to death was 2.3 months (range 0.3-7.9 months). Five patients who received chemotherapy after brain irradiation had a median survival of 4.4 months compared to 0.9 months for those who received no additional treatment after brain irradiation (P= .016). Most patients with brain metastasis from cervical cancer presented with neurologic sequelae. Brain irradiation improved these symptoms. Survival after diagnosis of brain metastasis was poor; however, patients who received chemotherapy after brain irradiation appeared to have improved survival.

Role of fine needle aspiration cytology in diagnosis of lung tumours--a study of 100 cases

The aim of this study was to assess the usefulness of fine needle aspiration cytology (FNAC) as a diagnostic method in lung tumour as well as to determine the incidence of lung cancer in various age and sex group and in relation with smoking. Hundred cases of lung tumours were investigated. Out of 100 patients, 88 were male and 12 were female. The age of patients varies from 23-78 years most of the patient were in the age group of 50-70 years. The most common tumour was squamous cell carcinoma (45%) followed by adenocarcinoma (22%), small cell carcinoma (16%) and large cell carcinoma (8%). Eighty out of 100 patient had history of smoking. Diagnostic accuracy of cytology with final histopathological report was established with accuracy rate of 95%.

Primary chondrosarcoma of lung: case report and review of literature

A case of primary chondrosarcoma of the left lung in 50 year-old man is presented. The tumor was diagnosed as primary chondrosarcoma of the lung after exclusion of any primary lesion elsewhere. Histologically, tumor consisted of predominantly chondromatous lesion. Immunohistochemistry showed that tumor cells positive for S-100 protein and vimentin, and negative for epithelial markers. On the basis of clinical, histological and immunohistochemical studies, the tumor was diagnosed as a primary chondrosarcoma of the lung.

Accuracy of cytologic diagnosis of central nervous system tumours in crush preparation

The aim of this study was to assess the usefulness and accuracy of cytologic smears by making crush preparation as a diagnostic method, in central nervous system tumors. 278 patients with central nervous system tumors were investigated. In 98 cases, material was obtained intraoperatively during craniotomy and in 180 cases stereotactic biopsies were done. In all the cases crush preparations were made, and cytologic diagnosis was correlated with final histologic diagnosis. 244 out of 278 patients showed correlation with histopathological diagnosis. So, in present study diagnostic accuracy was 87.76%. In 18 cases no definite diagnosis was made due to inadequate material. Majority of the patients were in age group 31 to 40 years (72 cases). The youngest patient was three years old and the eldest was 87 years old. The most common tumor in intracranial cavity was astrocytoma (56.68%), followed by meningioma (6.88%), medulloblastoma (5.66%) and ependymoma (5.56%). The most common tumor in intraspinal cavity was ependymoma (38.46%), followed by meningioma (23.07%) and schwannoma (23.07%). In conclusion, crush preparation is an effective, simple, rapid, relatively safe and reliable technique for the diagnosis of central nervous system tumors. Diagnostic accuracy of cytology with final histopathological report is established with accuracy rate of 87.76%.

Primary mucinous carcinoma of urachus--a case report

The authors describe a case of primary mucinous carcinoma of urachus in 65 years old male. Patient presented with hematuria with suprapubic mass. The patient underwent total cystectomy with en bloc excision of the tumor mass and umbilicus. Histological examination showed features of mucinous carcinoma of urachus. A clinicopathological study and brief review of literature is presented.

Cytological grading of breast neoplasia and its correlation with histological grading

Cytological grading of breast cancer is not well established despite histological grading having gained a strong foothold. In our study we have analyzed 50 cases of breast carcinoma which included invasive ductal carcinoma, invasive lobular carcinoma, mucinous carcinoma, stromal sarcoma, apocrine carcinoma, papillary carcinoma. Papanicolaou smears were graded according to established Hunt's, Simplified Black and Modified Black grading systems. They were then compared with the Scarff Bloom Richardson grading system. Simplified Black grading system has been recommended for cytological grading of breast neoplasia because of its lucidity and its reproducibility. Cytological grading of breast neoplasia is important for neo adjuvant chemotherapy and also for predicting the prognosis of the patient on FNAC alone. Incorporation of other parameters like apoptosis and bcl-2 is also recommended.

Clinicopathological prognostic factors of adult granulosa cell tumor of the ovary--a study of 37 cases

Adult granulosa cell tumor (GCT) of the ovary is the most common malignancy amongst the sex cord stromal tumors. Clinical stage, age, tumor size, residual disease and several histologic factors have been reported to be of prognostic significance. There were 839 ovarian malignancies at our institute during the period from 1998 to 2002. Out of 54 granulosa cell tumors, 40 cases were evaluable which includes 37 cases of adult GCT and 3 cases of juvenile GCT. They were studied retrospectively. Majority of patients presented with abdominal symptoms and FIGO stage I. All patients were treated surgically and 62.1% of adult GCTs were given post-operative chemotherapy. Clinical stage, presence of residual disease and tumor volume were the most important prognostic factors. Age of patient, menstrual status, post-operative chemotherapy, mitosis or histological patterns were of little significance in our study.

Spontaneous development of protective anti-T cell receptor autoimmunity targeted against a natural EAE-regulatory idiotope located within the 39-59 region of the TCR-V beta 8.2 chain

The development of experimental autoimmune encephalomyelitis (EAE) in Lewis rats is mediated by V beta 8.2+ T cells specific for myelin basic protein. One consequence of this biased expression of V beta 8.2 is the spontaneous development of regulatory T cells and antibodies against residues 39-59 of the V beta 8.2 sequence. Moreover, a synthetic V beta 8.2-39-59 peptide could induce protection against and speed recovery from EAE. T cells and antibodies specific for V beta 8.2-39-59 could transfer protection from EAE. Recently, we reported that the protective T cell epitope is subsumed within the V beta 8-44-54 sequence. We now report that protection induced by V beta 8-44-54 lasted at least 102 days and produced "split tolerance," enhancing anti-myelin basic protein antibody titers but reducing anti-myelin basic protein T cell frequency. The shorter V beta 8-44-54 peptide induced a distinct set of antibodies that did not cross-react with the longer V beta 8.2-39-59 peptide, although both specificities could stain V beta 8.2+ T cells and were equally protective against EAE. However, the V beta 8.2-39-59 peptide, but not the V beta 8-44-54 peptide, would appear to represent the natural idiotope: antibodies to V beta 8.2-39-59 that develop spontaneously during EAE could be boosted to higher titers only by the V beta 8.2-39-59, but not by other TCR peptides from the V beta 8.2 sequence, including V beta 8-44-54 that contains the functional T cell epitope. These results suggest that natural processing of the TCR V beta-chain favors the formation of a peptide that resembles the V beta 8.2-39-59 sequence. The B cell epitope present on the V beta 8-44-54 sequence was evident only in the absence of residues 39-43 and 55-59, suggesting that the two peptides possess distinct conformations. However, the V beta 8-44-54 B cell epitope is most likely expressed on the V beta 8.2+ T cells, either as a low affinity determinant on the intact TCR alpha/beta heterodimer or as a cryptic epitope bound in the cleft of surface MHC molecules.

Spontaneous development of protective anti-T cell receptor autoimmunity targeted against a natural EAE-regulatory idiotope located within the 39-59 region of the TCR-V beta 8.2 chain

The development of experimental autoimmune encephalomyelitis (EAE) in Lewis rats is mediated by V beta 8.2+ T cells specific for myelin basic protein. One consequence of this biased expression of V beta 8.2 is the spontaneous development of regulatory T cells and antibodies against residues 39-59 of the V beta 8.2 sequence. Moreover, a synthetic V beta 8.2-39-59 peptide could induce protection against and speed recovery from EAE. T cells and antibodies specific for V beta 8.2-39-59 could transfer protection from EAE. Recently, we reported that the protective T cell epitope is subsumed within the V beta 8-44-54 sequence. We now report that protection induced by V beta 8-44-54 lasted at least 102 days and produced "split tolerance," enhancing anti-myelin basic protein antibody titers but reducing anti-myelin basic protein T cell frequency. The shorter V beta 8-44-54 peptide induced a distinct set of antibodies that did not cross-react with the longer V beta 8.2-39-59 peptide, although both specificities could stain V beta 8.2+ T cells and were equally protective against EAE. However, the V beta 8.2-39-59 peptide, but not the V beta 8-44-54 peptide, would appear to represent the natural idiotope: antibodies to V beta 8.2-39-59 that develop spontaneously during EAE could be boosted to higher titers only by the V beta 8.2-39-59, but not by other TCR peptides from the V beta 8.2 sequence, including V beta 8-44-54 that contains the functional T cell epitope. These results suggest that natural processing of the TCR V beta-chain favors the formation of a peptide that resembles the V beta 8.2-39-59 sequence. The B cell epitope present on the V beta 8-44-54 sequence was evident only in the absence of residues 39-43 and 55-59, suggesting that the two peptides possess distinct conformations. However, the V beta 8-44-54 B cell epitope is most likely expressed on the V beta 8.2+ T cells, either as a low affinity determinant on the intact TCR alpha/beta heterodimer or as a cryptic epitope bound in the cleft of surface MHC molecules.

Poor reliability of the first meal tolerance test

The poor reproducibility of oral glucose tolerance test (OGTT) has been known for a long time. Some recent reports indicate that postprandial glycaemia achieved during the test is likely to be higher on the first occasion than on subsequent visits. We have analysed our recent data on meal tolerance tests (MTT) from this angle. Fifteen healthy subjects and 9 subjects having NIDDM were administered two essentially identical meals one or two weeks apart. In case of healthy subjects, the absolute as well as incremental postprandial glycaemia achieved at 0.5 h and 1.0 h on the first visit was significantly higher (P < 0.05) than on the subsequent visit. The effect of visit was insignificant in case of NIDDM subjects. The effect observed in healthy subjects may be due to the release of adrenaline during the first visit brought about by apprehension. In NIDDM subjects the apprehension is likely to be much less because of their having undergone such tests in the past. Hence a single casual OGTT or MTT is unreliable as a diagnostic tool in borderline cases of impaired glucose tolerance test. The test needs to be repeated at least once more to eliminate false positives.

Effect of coingestion of paracetamol on glycaemic response

Rate of gastric emptying is a frequently measured variable in glycaemic response studies. One of the indices employed for measurement of the gastric emptying rate is the blood level of paracetamol at frequent intervals of time following coingestion of paracetamol with the meal. But the effect of paracetamol itself on glycaemic response is not known. The present study was performed on ten healthy and five NIDDM subjects. Each subject underwent two meal tolerance tests in random sequence. On one occasion the meal was white bread; on the other occasion, the meal consisted of the same quantity of white bread and 1.5 g paracetamol. The postprandial glycaemica following the two meals was not significantly different. Thus the results validate the use of the paracetamol technique for gastric emptying in glycaemic response studies.

Sigma compounds derived from phencyclidine: identification of PRE-084, a new, selective sigma ligand

A series of compounds derived from phencyclidine (PCP) was examined in the sigma receptor and PCP receptor binding assays. The derivatives included compounds containing methylene, ethylene or carboxyl ethylene insertion between the cycloalkyl ring and the amine group of PCP. Various phenyl substitutions, cycloalkyl rings and amines of these derivatives were also examined. The methylene and ethylene insertions decreased the compounds' potencies at PCP receptors, whereas they increased the potencies at sigma receptors. The carboxyl ethylene insertion produced compounds with negligible potencies at PCP receptors while possessing high potencies for sigma receptors. One derivative (PRE-084; 2-(4-morpholino)ethyl 1-phenylcyclohexane-1-carboxylate hydrochloride) had an IC50 of 44 nM in the sigma receptor assay, an IC50 of more than 100,000 nM for PCP receptors and an IC50 higher than 10,000 nM in a variety of other receptor systems. In general, compounds with hydroxy-substituted phenyl groups tended to have decreased potency at sigma receptors, whereas methylphenyl and chlorophenyl substitutions increased potencies. Reduction of cycloalkyl ring size decreased potencies for sigma receptors and quaternized amine groups invariably lowered the compound's potencies. Conformational analysis indicated that PRE-084 fitted onto a pharmacophore model for the sigma ligands. The study describes a new, highly selective ligand for the sigma receptor. The results of this study also confirm distinctly different structural requirements for binding to sigma and PCP receptors and provide a new structural consideration for synthesizing sigma-selective compounds.

Glycaemic response to maize, bajra and barley

The postprandial glycaemic response to maize (Zea mays), bajra (Pennisetum typhoideum) and barley (Hordeum vulgare) was studied in a pool of 18 healthy volunteers and 14 patients having non-insulin-dependent diabetes mellitus (NIDDM). In response to maize, none of the variables examined was significantly different as compared to white bread. The glycaemic response to bajra was significantly lower than that to white bread in healthy subjects, but the two responses were indistinguishable in NIDDM subjects. The insulinaemic responses to bajra and white break were not significantly different in either group of subjects. The glycaemic response to barley was significantly lower than that to white bread in both groups of subjects. But the insulinaemic response to barley was significantly lower than that to white bread only in healthy subjects. In NIDDM subjects, there was a tendency for the response to barley to be higher than that to white bread 0.5 h after ingestion. Barley, with a low glycaemic index (68.7 in healthy and 53.4 in NIDDM subjects) and a high insulinaemic index (105.2) in NIDDM subjects seems to mobilize insulin in NIDDM. This makes it a specially suitable cereal for diabetes mellitus.

The binding of prototype lexitropsins to the minor groove of DNA: quantum chemical studies

Ab initio calculations (Hartree-Fock) using the 6-31 G basis set have been performed on two prototype lexitropsins or information-reading molecules. The latter are DNA minor groove binding agents related to the A.T recognizing netropsin in which each of the two N-methylpyrrole moieties is replaced in turn by 1-methylimidazole and which thereby confers the property of recognizing G.C sites.Ab initio treatment was possible by examining composities of separate non-conjugated segments of the molecules. Geometry optimized conformations, energies and distribution of electrostatic charges within the molecules were derived. The ab initio derived parameters of the geometry optimized conformations of these lexitropsins were used to interpret their interaction with different sequences within the minor groove of B-DNA.