Chemistry of clitoral gland secretions of the laboratory rat: assessment of behavioural response to identified compounds

The present investigations were carried out to find out the chemical nature of clitoral gland extracts and their involvement in reproductive and social behaviour. Homogenates of clitoral glands of mature estrous female rats were extracted with n-hexane and dichloromethane (1 : 1 ratio v/v) and analysed by gas chromatography linked mass spectrometry (GC-MS). Three peaks were found to be in higher concentration, which were identified as 6,11-dihydro-dibenz-b,e-oxepin-11-one (I); 2,6,10-dodecatrien-1-ol-3,7,11-trimethyl(Z) (II); and 1,2-benzene-dicarboxylic acid butyl(2-ethylpropyl) ester (III). Odour preference tests demonstrated that the first compound attracted conspecifics of the opposite sex. By contrast, the second and third compounds were found to attract both sexes. The results conclude that the clitoral gland of laboratory rat contains three major chemical compounds which have a unique function in maintaining social and reproductive status.

Direct detection of diarrheagenic Aeromonas from faeces by polymerase chain reaction (PCR) targeting aerolysin toxin gene

Detection of diarrheagenic Aeromonas specific aerolysin toxin (Aer) gene by PCR based assay and isolation, identification of diarrhea causing Aeromonas from faeces by culture methods were carried out in the Division of Active Surveillance, National Institute of Cholera and Enteric Diseases (NICED), Kolkata, India for a period of 12 months. Out of 602 faecal samples collected from patients with acute diarrhea admitted in Infectious Diseases (ID) Hospital, Kolkata, 68 (11.29%) samples were found to be possessing Aer gene by PCR technique. The conventional culture methods using selective media yielded only 64 (10.6%) Aeromonas strains from the same faecal samples. The different Aeromonas species possessing Aer gene identified by PCR based technique include A. hydrophila (55.8%), A. caviae (17.6%), A. veronii (10.2%), A. schubertii (4.4%), A. jandaei (2.9%) and A. trota (8.8%). The isolation and identification of Aeromonas by routine culture did not detect enterotoxigenic A. trota present in four diarrheal faecal samples. The failure of the growth of enterotoxigenic A. trota on selective media may be attributed to the ampicillin susceptibility of those strains. The quality control studies revealed that PCR method for the direct detection of Aer gene from the faeces has the sensitivity of 100% and specificity of 98%.

Diffuse crescentic glomerulonephritis in bacterial endocarditis

Renal involvement is common in patients with bacterial endocarditis. The most common bacteria are staphylococci and streptococci, and the commonest renal histopathological lesion is a diffuse proliferative and exudative type of glomerulonephritis. Very rarely, patients may present with an extensive glomerular epithelial crescent formation with a rapid deterioration in the renal function. This study reviews the published literature on diffuse crescentic glomerulonephritis in bacterial endocarditis and reports a 24-year-old male patient with endocarditis due to Capnocytophagia species, a gramnegative facultative anaerobic bacillus, which normally inhabits the oral cavity. Appropriate antibiotic therapy is essential to eradicate the infection. A brief course of corticosteroid therapy may be helpful in those with deteriorating renal function. Plasmapheresis may be useful in those with persistent hypocomplementemia, increased circulating immune complexes, and a progressive deterioration in the renal function. Removal of vegetation or valve replacement may be necessary. Prognosis is generally good.

ATF-7, a novel bZIP protein, interacts with the PRL-1 protein-tyrosine phosphatase

We have identified a novel basic leucine zipper (bZIP) protein, designated ATF-7, that physically interacts with the PRL-1 protein-tyrosine phosphatase (PTPase). PRL-1 is a predominantly nuclear, farnesylated PTPase that has been linked to the control of cellular growth and differentiation. This interaction was initially found using the yeast two-hybrid system. ATF-7 is most closely related to members of the ATF/CREB family of bZIP proteins, with highest homology to ATF-4. ATF-7 homodimers can bind specifically to CRE elements. ATF-7 is expressed in a number of different tissues and is expressed in association with differentiation in the Caco-2 cell model of intestinal differentiation. We have confirmed the PRL-1.ATF-7 interaction and mapped the regions of ATF-7 and PRL-1 important for interaction to ATF-7's bZIP region and PRL-1's phosphatase domain. Finally, we have determined that PRL-1 is able to dephosphorylate ATF-7 in vitro. Further insight into ATF-7's precise cellular roles, transcriptional function, and downstream targets are likely be of importance in understanding the mechanisms underlying the complex processes of maintenance, differentiation, and turnover of epithelial tissues.

Regulation of heparin-binding EGF-like growth factor expression in Ha-ras transformed human mammary epithelial cells

Heparin-binding epidermal growth factor-like growth factor (HB-EGF) mRNA and protein expression is induced by EGF in MCF-10A nontransformed and Ha-ras transfected human mammary epithelial cells. The anti-EGF receptor (EGFR) blocking monoclonal antibody (MAb) 225 and the EGFR tyrosine kinase inhibitor PD153035 were able to inhibit the induction of HB-EGF mRNA levels in MCF-10A cells. However, the Ha-ras transformed MCF-10A cells were more refractory to inhibition by these agents and only a combination of the 225 MAb and PD153035 was able to significantly abrogate HB-EGF induction by EGF. The anti-erbB2 MAb L26 which interferes with heterodimer formation was able to block HB-EGF induction in response to EGF in MCF-10A cells and in the Ha-ras transformed cells only when used in combination with either the 225 MAb or PD153035. The MEK inhibitor PD90859 completely blocked EGF induction of HB-EGF mRNA levels in the nontransformed and Ha-ras transformed MCF-10A cells, which indicates that MAPK is involved in the signaling pathway of HB-EGF induction by EGF. An increase in the levels of HB-EGF may, therefore, be an important contributor to oncogenic transformation that is caused by Ha-ras overexpression in mammary epithelial cells. J. Cell. Physiol. 186:233-242, 2001. Published 2001 Wiley-Liss, Inc.

Unexplained acute severe methaemoglobinaemia in a young adult

This report describes the case of an otherwise healthy young adult female, who presented with a 12-h history of progressive bluish discolouration of lips and limbs. She denied ingesting or inhaling any drug or substance. A high PaO2 in the presence of 'cyanosis' and 'dark blood' led to suspicion of methaemoglobinaemia. Co-oximetry revealed the methaemoglobin level to be 47%. A urinary screen for drugs of abuse was negative and blood methaemoglobin reductase activity was within the normal range. The aetiology was traced to dapsone detected in the urine by gas chromatography/mass spectrometry. The therapeutic and diagnostic approach in such patients is discussed.

RAS transformation causes sustained activation of epidermal growth factor receptor and elevation of mitogen-activated protein kinase in human mammary epithelial cells

Activation of the ras oncogene is an important step in carcinogenesis. Human MCF-10A mammary epithelial cells were transformed with a point-mutated form of the Ha-ras oncogene. Epidermal growth factor receptor (EGFR) phosphorylation levels were chronically elevated after EGF induction and the EGFR ligand-driven internalization rate was slower in Ha-ras transformed MCF-10A cells. Additionally, basal levels of p42/44 mitogen-activated protein kinase (MAPK) expression and enzyme activity were significantly higher in Ha-ras transformed cells, localized predominantly in the nucleus. The anti-EGFR monoclonal antibody (MAb) 225 and the EGFR tyrosine kinase inhibitor PD153035 blocked anchorage-independent growth of Ha-ras transformed cells in soft agar and were more effective when used in combination. The MEK inhibitor PD98059 and anti-erbB-2 MAb L26 also suppressed colony formation of Ha-ras transformed cells in soft agar. Therefore, Ha-ras transformation leads to an augmentation in signaling through the EGFR as a result of an increase in ligand-dependent phosphorylation, a decrease in its internalization and an up-regulation in basal p44/42 MAPK levels. These effects may contribute to uncontrolled growth of Ha-ras-transformed human mammary epithelial cells.

Intubating LMA guided awake fibreoptic intubation in severe maxillo-facial injury

PURPOSE

To describe control of the airway in a patient with severe maxillo-facial injury using intubating laryngeal mask guided awake fibreoptic intubation.

CLINICAL FEATURES

A 110 kg man presented with a severe facial injury due to a horse kick. Local examination showed a large transverse gaping laceration just beneath the nose, exposing the lower nasal cavities through to the posterior nasopharynx. It was planned to perform a surgical tracheostomy before surgical fixation of the maxilla and nasal bones. Considering the patient's weight, short neck and difficulty in lying flat, surgical tracheostomy under general anesthesia was considered the best option. Under topical anesthesia, an intubating laryngeal mask was introduced followed by a fibreoptic bronchscope. The endotracheal tube was threaded over the bronchoscope and airway control achieved.

CONCLUSIONS

The use of an intubating laryngeal mask avoids the need for manipulation of the head and neck and acts as a 'shield' for the fibreoptic bronchoscope from surrounding blood in patients with maxillo-facial injury. The use of the fibreoptic bronchoscope ensures intubation under vision.

RAS transformation causes sustained activation of epidermal growth factor receptor and elevation of mitogen-activated protein kinase in human mammary epithelial cells

Activation of the ras oncogene is an important step in carcinogenesis. Human MCF-10A mammary epithelial cells were transformed with a point-mutated form of the Ha-ras oncogene. Epidermal growth factor receptor (EGFR) phosphorylation levels were chronically elevated after EGF induction and the EGFR ligand-driven internalization rate was slower in Ha-ras transformed MCF-10A cells. Additionally, basal levels of p42/44 mitogen-activated protein kinase (MAPK) expression and enzyme activity were significantly higher in Ha-ras transformed cells, localized predominantly in the nucleus. The anti-EGFR monoclonal antibody (MAb) 225 and the EGFR tyrosine kinase inhibitor PD153035 blocked anchorage-independent growth of Ha-ras transformed cells in soft agar and were more effective when used in combination. The MEK inhibitor PD98059 and anti-erbB-2 MAb L26 also suppressed colony formation of Ha-ras transformed cells in soft agar. Therefore, Ha-ras transformation leads to an augmentation in signaling through the EGFR as a result of an increase in ligand-dependent phosphorylation, a decrease in its internalization and an up-regulation in basal p44/42 MAPK levels. These effects may contribute to uncontrolled growth of Ha-ras-transformed human mammary epithelial cells.

Identification of volatile compounds from cheek glands of lesser bandicoot rats and assessment of behavioural response for identified compounds

Check gland secretions were collected from sexually mature male and female rats to identify the volatile compounds using gas chromatography linked mass spectroscopy with a modified head space technique. Twenty one volatile fractions including alkanes, aliphatic acids, esters and alcohols were found. Three compounds viz. 3-octen-1-ol (E) (I), cyclopentane undecanoic acid (II) and 2,4,6,8 tetramethyl-l-undecane (III) were present in very high concentrations in both male and female rats. In addition, the estrus female contained another compound, L-alanine, 1,1-dimethyl ethyl ester. On the basis of odour preference tests the compounds I, II and III were found to attract both male and female of the homotypic species. In contrast, the fourth compound present in the female attracts the opposite sex. The results suggest that the volatile fractions have unique function and the level of attraction varies from compound to compound.

Severe head injury patients in a multidisciplinary ICU: are they a burden?

OBJECTIVE

Patients with severe head injury (HI) are often considered to be a burden in a multidisciplinary intensive care unit (ICU). This study was undertaken to compare the severe closed HI patients with all other patients in the ICU in terms of age group involved, stay in the unit, complications and outcome.

DESIGN

Retrospective analysis.

SETTING

Multidisciplinary ICU of a tertiary care hospital in Northern India.

PATIENTS AND PARTICIPANTS

All the patients admitted to the ICU between January 1995 and December 1997. The patients were classified into two groups: group A comprising patients with severe closed HI and group B consisting of all other patients.

RESULTS

The mean age of the patients was around 30 years in both the groups. The average stay of the patients in the unit was 12.71 +/- 11.9 days in group A, compared to 9.9 +/- 14.4 days for group B (p < 0.05). The duration on the ventilator or on an endotracheal airway was not different between the groups (p > 0.05). The mortality in group A was 46.8 % and that in group B was 38.5 % (p > 0.05). The mortality was directly proportional to the age in group A. Hypotension, renal failure and septicaemia were the commonest complications in both the groups but the difference was not statistically significant.

CONCLUSIONS

This study demonstrates that patients with severe HI do not pose an extra burden in a multidisciplinary ICU.