MIXED GERM CELL TERATOMATOUS TUMOUR OF TESTIS IN ADULTS: DIAGNOSTIC CHALLENGES FOR A HISTOPATHOLOGIST (case report)

Background. Testicular tumours account for approximately 1-2 % of the total cancer cases in the male population globally and show higher incidence in the younger male age group of up to 15 years. The majority (~98 %) of testicular tumours are observed to be of the germ-cell origin which can either be of seminomatous type or non-seminomatous type. The non-seminomatous germ cell neoplasm may be pure or of mixed subtype. Objective was to emphasize the rare case of mixed germ cell teratomatous tumour of testis in adult man.Methods.  A mixed germ cell teratomatous tumour of testis comprising of yolk sac tumour and embryonal carcinoma in an adult Indian male is reported in the research.Results. A 45 year-old Indian male presented with enlargement of right testis which was found to be an encapsulated right testicular tumour on exploratory surgery which was followed by radical orchiectomy. Serum AFP and β-hCG levels were elevated to 380 ng/ml and 590 mg/ml respectively. Histopathology revealed a mixed germ cell teratomatous tumour of testis comprising of yolk sac tumour and embryonal carcinoma.Conclusions. In adults teratomas occur usually as a component of mixed germ cell tumours. However in the present case teratomatous embryoid yolk sac germ cell tumour of testis was observed in an Indian adult male. The prognosis of embryoid germ cell tumours of testis is generally poor. The possibility of this condition should always be considered in all cases that present with a testicular lump.

Filarial abscess: Aspiration of adult gravid female worm from submandibular region, an unusual presentation

Microfilaria is a major public health problem in tropical and subtropical countries and is an endemic problem in India. Wuchereria bancrofti is the most common filarial infection. In some cases, microfilariae and adult filarial worm have been incidentally detected in fine-needle aspirates of various lesions; detection of microfilaria from subcutaneous site or from abscess site is even rarer. We here report an unusual case of Bancroftian microfilariasis in a 68-year-old female coming from endemic area presenting with right submandibular abscess. Our aim is to highlight the chances of finding microfilaria and adult worm in cytology of an unsuspected case at an unusual site.

Recurrent angio-fibroma of breast masquerading as phyllodes tumor

A young Indian female presented with a recurring tumor in the right breast masquerading as phyllodes tumor. Patient had history of five times excision and recurrences of the tumor, diagnosed as fibrous phyllodes of the breast. Presently, a well-circumscribed tumor of about 10 cm size, comprising of benign fibrous-angiomatous tissue with evidence of foci of pyogenic vasculitis was observed. Immuno-histochemical markers for the myo-epithelial and epithelial elements excluded the possibility of fibrous phyllodes, inflammatory myofibroblastic tumor, desmoid fibromatosis, and metaplastic carcinoma. The present findings were diagnostic of an inflammatory angio-fibroma of the right breast, not reported in the earlier literature. The observations indicated that the female breast may be susceptible to spontaneous productive and common-antibiotic-resistant focal septic vascular inflammation giving rise to angio-fibromatous proliferation producing a well-defined tumor mass in the breast, distinguishable from the other breast lesions by the connective tissue stains and immuno-histochemical markers.

Evolution of antimicrobial resistance and serotype distribution of Streptococcus pneumoniae isolated from children with invasive and noninvasive pneumococcal diseases in Algeria from 2005 to 2012

Pneumococcal infections are a major cause of morbidity and mortality in developing countries. The introduction of pneumococcal conjugate vaccines (PCVs) has dramatically reduced the incidence of pneumococcal diseases. PCVs are not currently being used in Algeria. We conducted a prospective study from 2005 to 2012 in Algeria to determine antimicrobial drug resistance and serotype distribution of Streptococcus pneumoniae from children with pneumococcal disease. Among 270 isolated strains from children, 97 (36%) were invasive disease; of these, 48% were not susceptible to penicillin and 53% not susceptible to erythromycin. A high rate of antimicrobial nonsusceptibility was observed in strains isolated from children with meningitis. The serotype distribution from pneumococci isolated from children with invasive infections was (by order of prevalence): 14, 1, 19F, 19A, 6B, 5, 3, 6A and 23F. Multidrug resistance was observed in serotypes 14, 19F, 19A and 6B. The vaccine coverage of serotypes isolated from children aged <5 years was 55.3% for PCV7, 71.1% for PCV10 and 86.8% for PCV13. Our results highlight the burden of pneumococcal disease in Algeria and the increasing S. pneumoniae antibiotic resistance. The current pneumococcal vaccines cover a high percentage of the circulating strains. Therefore, vaccination would reduce the incidence of pneumococcal disease in Algeria.

Effect of short term zinc supplementation on iron status of children with acute diarrhea

OBJECTIVE

To study the effect of short term (2 wk) zinc supplementation on hemoglobin and iron status of children with acute diarrhea.

METHODS

This study was a prospective, open label, single arm interventional trial conducted from June 2008 through October 2009 in a teaching hospital of North India. Three to sixty months old children presenting with acute diarrhea participated in the study. Subjects were supplemented with recommended doses of oral zinc gluconate for 2 wk. Changes in levels of hemoglobin, serum iron, total iron binding capacity, and serum ferritin were the main outcome measures.

RESULTS

Sixty-two patients completed the study successfully. The prevalence of anemia before and after 2 wk of zinc supplementation remained unchanged. However, a small decline (p > 0.05) was observed in mean hemoglobin (from 8.95 ± 1.4 to 8.73 ± 1.43 g/dL), serum iron (79.56 ± 45.81 to 78.61 ± 44.41 μg/dL) and ferritin (84.77 ± 45.35 to 83.55 ± 44.10 ng/mL) levels. Total iron binding capacity increased from 331.60 ± 109.72 to 341.30 ± 119.90 μg/dL post supplementation (p > 0.05).

CONCLUSIONS

Even though statistically insignificant, the small change observed in the levels of hemoglobin, and indicators of iron status following short term zinc supplementation might assume significance in some settings in developing countries where children receive short courses of zinc repeatedly for frequent diarrheal episodes.

Sclerosing stromal tumour of the ovary presenting as precocious puberty: a rare neoplasm

A 7-year-old Indian girl presented with symptoms of excessive development of breasts, early menarche, growth of pubic hairs, accelerated growth and abdominal distension. On clinical examination, a large right abdominopelvic mass was palpable. MRI revealed a large, heterogeneous, solid and cystic tumour in the right adnexal region, suggestive of an ovarian neoplasm. The hormonal profile showed markedly elevated oestradiol and low follicle-stimulating hormone levels. Clinical diagnosis of precocious puberty with right ovarian mass was concluded. Right-sided salpingo-oophorectomy was performed. Histopathology showed features consistent with sclerosing stromal tumour of the ovary. Postoperatively, signs and symptoms of precocity gradually regressed and her serum oestradiol level came down to normal. This is the first reported case from India.

Reticular schwannoma mimicking myxoid sarcoma

Reticular/microcystic schwannoma is a recently described rare distinctive variant of schwannoma with a predilection for gastrointestinal tract. Its occurrence in soft tissue is extremely rare. We report a case of reticular/microcystic variant of schwannoma in a 55-year-old Indian woman who presented with a painless slow-growing swelling in the right forearm for the past 6 months. MRI findings suggested myxoid sarcoma. However, histological and immunohistochemical findings in the excised specimen were consistent with reticular/microcystic variant of schwannoma. This case report emphasises that the diagnosis of reticular/microcystic schwannoma should always be considered in cases where myxoid sarcomas are suspected as it can mimic malignant myxoid sarcomas, clinically and radiologically, thereby avoiding aggressive intervention and overtreatment.

White-blue pyelocalyceal cyst with hydrotic glomerulonephritis

A 5-month-old male infant presented with a 15 day history of distension of abdomen. On clinical examination, a soft lump was palpable in the left lumbar region. Radiological findings suggested an enlarged non-functional left kidney with ureteropelvic adhesive obstruction. The left renal mass was excised and submitted for histopathological examination. The excised renal mass was cystic with its wall partly white and partly blue. Gross and histopathological findings were diagnostic of a white-blue pyelocalyceal cyst with hydrotic glomerulonephritis. This entity needs to be differentiated from a large number of other cystic diseases of the kidney. Intrauterine screening and diagnosis may be significant for a possible early intrauterine uro-laparoscopic recanalisation of the pyeloureteral obstruction to save the affected kidney.

Tubercular thyroiditis with multinodular goitre with adenomatous hyperplasia: a rare coexistence

A 32-year-old Indian woman presented with swelling in the anterior part of the neck for the last 3 years. Clinical and radiological examination and fine needle aspiration cytology suggested the diagnosis of multinodular goitre. A subtotal thyroidectomy was performed by the surgeon and the specimen was submitted for the final diagnosis. Histological examination of the specimen revealed multiple caseating tubercular granulomas coexistent with multinodular goitre and adenomatous hyperplasia. The sections demonstrated acid-fast tubercle bacteria, confirming the diagnosis of tubercular thyroiditis. This case emphasises that tubercular thyroiditis should always be considered in patients with thyroid swelling or nodule, in countries where the prevalence of tuberculosis is high.

Mature embryoid teratoma in the wall of a mucinous cyst adenoma of ovary in multiparous female

A collision tumour in ovary comprising a small ovoid embryoid mature teratoma in the surface wall of large mucinous cyst adenoma is reported in a 36-year-old female and its pathogenesis is discussed. The oval teratoid mass externally to the mucinous cyst lining did not show any columnar epithelial or mucin-secreting cyst. Findings suggested that the mature embryoid teratoma originated from ovarian germ cell rest in the surface wall of the cyst adenomatous neoplasm. Another possibility could be that the mature embryoid teratoma resulted from parthenogenesis of ovum together with the mucinous adenoma cysts by epithelial metaplasia of the follicular lining.

Pattern of oestrogen, progesterone and Her2neu receptors expression in a heterogeneous carcinoma of the breast in a lactating woman

Oestrogen-progestrone-Her2neu receptor status was studied in various loci/foci of heterogeneous carcinoma of the breast and its metastatic secretory component in the lymph node in a lactating woman. All the carcinoma variants were negative for the trio markers except tumour components evolved to secretory or lactating carcinoma, which showed focal positivity. Findings showed that oestrogenic receptors, progesterone receptors and Her2neu negative primitive carcinoma in a heterogenous breast cancer may evolve into oestrogen receptor, progesterone receptor and Her2neu positive secretory/lactating carcinoma alongside other receptor negative carcinoma variants. Focal marker positivity/negativity underlined the fact that a diagnostic/prognostic marker status report may account for the tumour area included in the section/sample only. Study of the immune marker expression/status in various loci may help identification of the components, morphogenesis and dynamics of heterogeneous carcinoma of the breast.

Septic disruption of lactiferous ducts with heterogeneous carcinoma of the breast in a lactating woman

This report documents the diagnostic histopathological features of heterogeneous breast carcinoma following sepsis and disruption of the lactiferous ducts in a lactating woman and discusses the pathogenesis. Sections from the nipple revealed disrupted collecting lactiferous ducts presenting with intraduct precarcinoma and carcinoma of the epidermoid type, and attached reparative sprouts lined by lactiferous cells. Breast lobules showed generalised benign adenotic change with various foci of carcinoma microscopically identifiable as intraduct primitive lactiferal ectodermal carcinoma, lactating carcinoma, primitive neuroendocrine carcinoma and myoepithelioid granulomatous carcinoma. The findings led to the conclusion that the lactiferous ducts are susceptible to sepsis and disruption, which may predispose a patient to breast carcinoma. The pattern of carcinoma suggested that lactiferous epithelial cells behaved colonially, with different metaplastic changes, precarcinoma and carcinoma.

Apoptotic effect of green tea polyphenol (EGCG) on cervical carcinoma cells

The objective of this study was to probe the apoptotic effect of green tea polyphenol epigallocatechin-3-gallate (EGCG) on cervical carcinoma cells. This study was conducted in Departments of Pathology and Biochemistry, Jawaharlal Nehru Medical College, Aligarh Muslim University, Aligarh, India over a span of one and half years from January 2005 to August 2006. Caspase-3 assay was performed on monocytes isolated from cervical carcinoma patients and cultured with EGCG; cytosmears and sections from cervical carcinoma tissue cultured with EGCG were prepared for the morphological evidence of apoptosis. EGCG in a dose of 5 μg/ml and 10 μg/ml increased the caspase-3 levels in human cells. Cytosmears and sections from cervical carcinoma tissue cultured with EGCG showed better differentiation and increased number of apoptotic cells as compared to non EGCG controls. The number of such cells was increased more in 48 hours than in 24 hours. EGCG in a dose of 5 μg/ml and 10 μg/ml promoted apoptotic preparedness of human cells and induced apoptotic change in cervical carcinoma cells.

Pyelocalyceal cysts with hydrotic nephritis of the kidney: case of a unilateral congenital developmental anomaly

This report describes the diagnostic, morbid, anatomical and histopathological features of pyelocalyceal cysts with hydrotic nephritis of the kidney in a 3-year-old boy, and discusses the pathogenesis. Calyceal cysts gave rise to a 'large blue cystic lobulated kidney' with microscopic changes in nephrons identifiable as 'hydrotic nephritic glomerulosclerosis'. Pelvic and calyceal cysts were identifiable by location, number, arrangement, and morbid anatomical and microscopic features of their lining walls. Such cysts may develop due to partial or complete obliterate adhesions at the uretero-pelvic and pyelocalyceal junctions. Patent calyceo-tubulonephric junctions in such cases may give rise to hydrotic nephritis. Pyelocalyceal cystic disease with hydrotic nephritis of the kidney needs to be distinguished from megacalycosis and hydronephrosis and deserves recognition. Observations in this case may provide the basis for future classifications of cystic renal diseases.

Immature embryoid teratoma of the gall bladder: case of a primary primitive neoplasm

This study presents diagnostic histopathological features of a primary embryoid teratomatous neoplasm in the gall bladder of a 60-year-old woman, and also discusses its pathogenesis. Sections revealed immature and typical embryoid bodies and dispersed syncytial trophoblasts along with mature and immature neuroectodermal and mesodermal elements. The residual endothelial lining of the gall bladder showed in situ and proliferative changes characteristic of an endodermal tumour. Ultrasonographic and magnetic resonance imaging findings of the rest of the abdominal and pelvic organs appeared normal. Results show that the mature adult gall bladder is susceptible to primary neoplasms of a primitive nature ranging from immature embryoma and teratoma to neuroectodermal tumour. Such primitive neoplasms in adult organs where benign neuroectodermal elements are present may evolve from a constituent cell of an adult organ acquired during embryogenesis from a morula that differentiated into trophoblastic (outer) and embryoblastic (inner) cells, and existing dormant cells at rest until reactivation during oncogenesis.

Prevalence of beta-lactams resistance among Escherichia coli clinical isolates from a hospital in Algiers

A high prevalence of beta-lactams resistance among Enterobacteriaceae have been reported worldwide; however, there are not sufficient data on this issue in Algeria. beta-Lactams susceptibility of 203 Escherichia coli clinical isolates was determined by agar diffusion method, and production of extended-spectrum beta-lactamases (ESBL) was screened by double-disk synergy test. This analysis showed five well-defined phenotypes: 1) 62 isolates (30.5%) were susceptible to all beta-lactams; 2) 135 isolates (66.5%) presented a broad-spectrum beta-lactamases phenotype (BSBL); 3) three isolates (1.5%) were defined as producing ESBLs; 4) two isolates (1%) were AmpC cephalosporinase producers; and 5) one isolate (0.5%) presented a phenotype of cell-decreased permeability to beta-lactams. Isoelectric focusing revealed beta-lactamases with isolectric points of 5.4 or 7.6 for isolates with BSBL phenotype; approximately 9.0 for two ESBL isolates; 5.4, 7.6 and approximately 9.0 for the remaining ESBL isolate; and 5.4 and approximately 9.0 for the AmpC isolates. The cefotaxime hydrolysis corresponds to the basic bands with an isoelectric point of approximately 9.0. Conjugation assay showed transfer of penicillinase and AmpC resistance phenotypes and their corresponding beta-lactamases to recipient E. coli BM21 in association with plasmids of 71.4 kb for the AmpC isolates and from 40-56 kb for penicillinase isolates. This result showed that the AmpC phenotype is plasmid mediated. ESBL isolates were found not to transfer their resistance through conjugation experiment. Polymerase chain reaction (PCR) experiments using primers specific to blaTEM, blaAmpC and blaCTX-M genes showed specific amplification with blaCTX-M primer for two ESBL isolates; blaTEM and blaCTX-M for the remaining ESBL isolate; and blaTEM and blaAmpC for the AmpC isolates and their corresponding transconjugants. The study showed a high rate of isolates producing penicillinase, and low frequencies of AmpC and ESBL phenotypes. AmpC beta-lactamases were plasmid mediated, and ESBLs belong to the CTM-M type.

Head and neck masses in children: A clinicopathological study

Fifty children with head and neck masses were evaluated clinically and pathologically. Inflammatory swellings constituted the majority (54%). Congenital - developmental malformations were the next common lesions (30%) and neoplastic masses constituted the rest (16%). Tuberculous lymphadenitis was found to be the single most common etiology (28%). Among congenital-developmental malformations, cystic hygroma was the most frequent lesion. The incidence of branchial cleft abnormalities was found to be low and no thyroglossal duct cyst was observed in this series. Among the neoplastic masses malignant lesions were more common than benign tumours and lymphoma was the most common head and neck malignancy observed.

Gc-olfactometry with solid phase microextraction of aroma volatiles from heated and unheated orange juice

Solid phase micro extraction, SPME, the solventless headspace volatile extraction technique, was combined with GC-olfactometry (GCO) to examine changes in aroma active volatiles when orange juice was heated. Juice volatiles extracted from the static headspace using SPME (carboxen-polydimethylsiloxane fiber) were compared to liquid-liquid extracts. The SPME extract contained a greater proportion of terpenes. Limonene, myrcene and alpha-pinene comprised 86% of total FID peak area whereas they only comprised 24% in the pentane:ether extract. Aroma active volatiles were evaluated by three trained panelists using Osme, a GCO time-intensity procedure. Eighteen aroma active peaks were common to both heat treated and untreated juice headspace extracts. Six peaks were observed only in unheated extracts and five were found only in extracts from heated juices. Relative amounts of acetaldehyde decreased with increasing headspace exposure time and elevated desorption temperatures.

2-Methyl-3-furanthiol and methional are possible off-flavors in stored orange juice: aroma-similarity, NIF/SNIF GC-O, and GC analyses

The occurrence of methional in fresh orange juice, and possible occurrence of beta-damascenone in heated orange juice, has been previously suggested. Here we report on the occurrence of 2-methyl-3-furanthiol in the headspace, collected by solid-phase micro-extraction, of fresh, pasteurized, and stored orange juice. The contents of 2-methyl-3-furanthiol and methional were quantified, and the relative level of beta-damascenone was estimated, in the headspace of fresh, pasteurized, and stored orange juices using the nasal impact frequency (NIF) and surface of NIF (SNIF) GC-Olfactometry procedure. 2-Methyl-3-furanthiol concentrations were 2 ng/L in fresh and pasteurized Shamuti orange juice, and 270 ng/L in stored juice of the same variety. Methional concentrations were 550, 830, and 11,550 ng/L in fresh, pasteurized, and stored pasteurized juices, respectively. beta-Damascenone content appeared to have increased during pasteurization and storage. Aroma-similarity experiments strongly suggest that 2-methyl-3-furanthiol and methional, at the levels found in stored orange juice (21 days at 35 degrees C), contribute to stored orange juice off-flavor.

Analysis of Furaneol in tomato using dynamic headspace sampling with sodium sulfate

High-flow dynamic headspace sampling with excess anhydrous sodium sulfate was found to be an effective method of isolating Furaneol from fresh tomatoes. Quantitative analysis was carried out by gas chromatography using maltol as internal standard. Furaneol was found in the highest concentrations (660-1100 ppb) in the summer crop of home-grown tomatoes and in some of the greenhouse hydroponically grown tomatoes, which are ripened on the plant before being transported to the supermarkets. Furaneol was found in the lowest concentrations (38-180 ppb) in the common ethylene-ripened, field-grown, supermarket tomatoes.

Quality measures in applications of image restoration

We describe a new method for the estimation of image quality in image restoration applications. We demonstrate this technique on a simulated data set of fluorescent beads, in comparison with restoration by three different deconvolution methods. Both the number of iterations and a regularisation factor are varied to enforce changes in the resulting image quality. First, the data sets are directly compared by an accuracy measure. These values serve to validate the image quality descriptor, which is developed on the basis of optical information theory. This most general measure takes into account the spectral energies and the noise, weighted in a logarithmic fashion. It is demonstrated that this method is particularly helpful as a user-oriented method to control the output of iterative image restorations and to eliminate the guesswork in choosing a suitable number of iterations.

Mentoring senior house officers. Is there a role for middle grade doctors?

OBJECTIVES

To determine whether the mentoring scheme currently used has an impact on the training of senior house officers and also determine if they are willing to accept middle grade mentors.

METHODS

A questionnaire comprising 10 questions was sent to all the senior house officers employed in the emergency departments of two large inner city teaching hospitals and three large district hospitals. Most of the questions required a simple yes/no response.

RESULTS

Most of the senior house officers had mentors allocated to them but felt the scheme was not satisfactory probably because they had low expectations. Most were happy to have middle grade doctors as mentors.

CONCLUSIONS

Senior house officers have a low expectation of the present system and seem willing to accept middle grade doctors as mentors.

Arterial thoracic outlet compression syndrome: a differential diagnosis of painful right supraclavicular swelling?

The narrow triangle described by the first rib inferiorly, the scalenus medius posteriorly and the scalenus anterior anteriorly confines the neurovascular structures of the upper extremities as they exit from the mediastinum and the spinal canal. In patients with cervical ribs or abnormal congenital fibrous connections between the cervical transverse process and the first rib, the base of the triangle maybe raised to the height of the vertebrae resulting in the angulation or compression of the neurovascular structures. This compression and angulation results in the syndrome known as thoracic outlet compression syndrome (TOCS) (Mann et al, 1995).

Sucrose-stimulated subsecond transient increase in cGMP level in rat intact circumvallate taste bud cells

Initial sweet taste transduction is expected to occur in the subsecond time range. We demonstrate a rapid and transient (75-250 ms) increase of cGMP (but not cAMP) level in rat intact circumvallate taste cells after stimulation by sucrose. This rapid increase does not occur in nonsensory epithelial cells. Pretreatment with a nonspecific phosphodiesterase (PDE) inhibitor (IBMX), a specific cAMP-PDE4 inhibitor (denbufylline), or an adenylyl cyclase activator (forskolin) all increased basal cAMP and abolished the sucrose-stimulated cGMP increase at 150 ms. Pretreatment with a soluble guanylyl cyclase inhibitor (1H-[1,2,4]oxadiazolo[4, 3-a]quinoxalin-1-one) reduced, whereas a specific cGMP-PDE inhibitor (zaprinast) abolished, the sucrose-stimulated cGMP increase. It is proposed that cGMP is involved in the initial stage of sugar taste transduction and that cGMP is more significant than cAMP at this stage. Activation of soluble guanylyl cyclase and inhibition of cGMP-PDE may be involved in the transient elevation of cGMP in response to sucrose stimulation. Moreover, it appears that cAMP level must remain low for sucrose to stimulate an increase in cGMP.

Photoreversible modulators of Escherichia coli beta-galactosidase. 1-Benzoyl-1-cyano-2-(4,5-dimethoxy-2-nitrophenyl)-ethene and 1,1-dicyano-2-(4,5-dimethoxy-2-nitrophenyl)-ethene

Beta-galactosidase (EC 3.2.1.23) is known to be inhibited by some thiol reagents. 1-Benzoyl-1-cyano-2-(4,5-dimethoxy-2-nitrophenyl)-ethene (1) was shown to be an irreversible inhibitor, while 1, 1-dicyano-2-(4,5-dimethoxy-2-nitrophenyl)-ethene (2) was demonstrated as a positive irreversible modulator causing a rise of up to 186% in beta-galactosidase activity. Compound 2 is, however, an irreversible inhibitor of the cysteine proteinase papain (preceding paper). Kinetic values of beta-galactosidase at pH 8.3 with o-nitrophenyl beta-D-galactopyranoside (ONPG) as the substrate and for compounds 1 and 2 were determined and in view of model experiments, it was assumed that both compounds possibly reacted with the thiol side chain of Cys in the active site inducing allosteric changes in the enzyme. Since the enzyme, modified by compound 1 or 2, was a 2-nitrobenzyl derivative, near-UV irradiation resulted in a recovery of up to 91% and a reduction of the enzyme's activity to 90%, respectively.

Inhibition of Papaya latex papain by photosensitive inhibitors. 1-(4,5-dimethoxy-2-nitrophenyl)-2-nitroethene and 1,1-dicyano-2-(4,5-dimethoxy-2-nitrophenyl)-ethene

1-(4,5-Dimethoxy-2-nitrophenyl)-2-nitroethene (1) was shown to be an irreversible inhibitor of papain (EC 3.4.22.2), causing a complete inhibition (120 min preincubation, pH 8.0), assuming that it attached to Cys-25 at the active site of the enzyme (while a short preincubation time caused activation). Only partial inhibition of papain was achieved, however, with 1,1-dicyano-2-(4,5-dimethoxy-2-nitrophenyl)-ethene (2), a compound synthesized in this work, which is also an irreversible inhibitor of papain. Since both compounds 1 and 2, and in each case of the inhibited enzyme, were 2-nitrobenzyl derivatives, they and the modified enzyme were expected to be photosensitive. Indeed, irradiation of the inhibited enzyme in the presence of mercaptoethanol resulted in a full recovery of the enzyme activity following inactivation with compound 1 (similar to our previous finding with beta-galactosidase) and up to 67% recovery following inhibition with compound 2.

Rapid entry of bitter and sweet tastants into liposomes and taste cells: implications for signal transduction

Some amphipathic bitter tastants and non-sugar sweeteners are direct activators of G proteins and stimulate transduction pathways in cells not related to taste. We demonstrate that the amphipathic bitter tastants quinine and cyclo(Leu-Trp) and the non-sugar sweetener saccharin translocate rapidly through multilamellar liposomes. Furthermore, when rat circumvallate (CV) taste buds were incubated with the above tastants for 30 s, their intracellular concentrations increased by 3.5- to 7-fold relative to their extracellular concentrations. The time course of this dramatic accumulation was also monitored in situ in rat single CV taste buds under a confocal laser-scanning microscope. Tastants were clearly localized to the taste cell cytosol. It is proposed that, due to their rapid permeation into taste cells, these amphipathic tastants may be available for activation of signal transduction components (e. g., G proteins) directly within the time course of taste sensation. Such activation may occur in addition to the action of these tastants on putative G protein-coupled receptors. This phenomenon may be related to the slow taste onset and lingering aftertaste typically produced by many bitter tastants and non-sugar sweeteners.

Sexuality during pregnancy in Pakistani women

OBJECTIVE

We investigated the patterns of sexual activity during pregnancy and explored all beliefs related to coitus during pregnancy in women with the objective of promoting awareness and assisting health care providers in understanding and dispelling fears/misconceptions prevalent in our culture.

METHODS

A cross-sectional, KAP (Knowledge, Attitude, Practice) study was conducted using questionnaires to interview 150 healthy pregnant women attending antenatal clinics at Aga Khan University Hospital (AKUH) and Lady Dufferin Hospital, both located in Karachi, Pakistani. Data was analysed using Epi Info 6 statistical package.

RESULTS

The mean frequency of intercourse during pregnancy (1.6 times/week) was less than before pregnancy (3.5 times/week). Husbands were the main initiators of sexual activity (44%) while the wives only rarely did so (0.7%). Some (13.3%) women felt it served to keep husbands around. Coitus during pregnancy was gratifying in 64.7% and painful in 37.3% of respondents. Most (45.4%) believed coitus was harmful for the foetus. Others (28.7%) thought it did not make any difference whereas 4.7% believed that it made a difference if the foetus was female by gender. 22.7% women believed that coitus during pregnancy caused abortions early in pregnancy and 6.7% that it induced pre-term labour. 26% did not know the means by which the harmful effects were produced but still maintained their beliefs. Some (10.7%) thought it could actually help widen the birth canal and facilitate labour. Majority (85.3%) believed that frequency should be lowered during pregnancy, 10% thought that it should be continued as before and 4% that it should be stopped completely.

CONCLUSION

This study suggests a mixed attitude towards sexuality in pregnancy with a tilt towards the belief that it is harmful and should therefore be decreased during pregnancy, specially during the last trimester. It is the responsibility of health care providers to dispel fears and clarify any misconceptions regarding such matters.

The delta-selective opioid peptide dermenkephalin and the mu-selective hybrid peptide dermenkephalin-[1-4]-dermophin-[5-7] display strikingly different conformations despite identical tetrapeptide N-termini. A quantitative 2-D NMR and molecular modeling analysis

The selective recognition of the aminoterminal binding pharmacophore Tyr-D-Xaa-Phe of the opioid heptapeptide dermorphin, Tyr-D-Ala-Phe-Gly-Tyr-Pro-Ser-NH2 (DRM)1, and of dermenkephalin, Tyr-D-Met-Phe-His-Leu-Met-Asp-NH2 (DREK), by the mu-opioid receptor and delta-opioid receptor, respectively, depends upon the constitution / conformation of the C-terminal tripeptide. The hybrid peptide DREK-[1-4]-DRM-[5-7] is very potent at, and exquisitely selective for the mu-opioid receptor, and differs only from dermenkephalin by its C-terminal tripeptide. Comparison of the structural features of DREK-[1-4]-DRM-[5-7] and dermenkephalin by nmr analysis and molecular modeling revealed striking differences, as well in the trans (Tyr5 - Pro6) isomer (population 75%) than in the cis isomer.. Whereas the folded C-terminal tail of dermenkephalin influenced the tertiary structure of the N-terminal tetrapeptide and placed the Tyr1 and Phe3 aromatic rings in definite orientations that are best suited for the delta-receptor, there were only weak contacts, as shown by NOE data, between the aminoterminal and carboxyterminal parts of the hybrid peptide. This promoted increased flexibility of the whole backbone and relaxed orientations for the side-chains of Tyr1 and Phe3 that are compatible with the mu-receptor but unsuitable for the delta-receptor. The steric hindrance introduced by Pro6 in DREK-[1-4]-DRM-[5-7], plus the absence of large hydrophobic side-chains in positions 5 and 6 may prevent close contacts between the N-terminal and C-terminal domains and reorientation of the main pharmacophoric elements Tyr1 and Phe3.

Prognostic indicators of childhood acute viral encephalitis

OBJECTIVE

To devise a set of clinical signs and laboratory parameters that would help clinicians assess prognosis in patients and plan appropriate management.

METHODS

Medical records of 147 paediatric cases (with a discharge diagnosis of acute viral encephalitis) admitted over a ten year period from 1987 to 1997 were reviewed and relevant information collected on a data extraction form.

RESULTS

Of 147 patients, 24 (16.3%) died and 48 (32.7%) were left with severe neurological deficits. A GCS (Glasgow Coma Scale) score between 6-10 had an association with poor outcome (OR = 2.62, Chi-square = 5.57, p-value = 0.018) and that a GCS score of > or = 5 was even more strongly suggestive of poor outcome (OR = 5.49, Chi-square = 12.08, p-value = 0.0005). A history of having seizures, for more than 3 days, also showed a strong association with poor outcome (OR = 3.66, Chi-square = 5.46, p-value = 0.019).

CONCLUSION

Patients with an increased risk of death and severe disability can be identified using a few guidelines. Of these, a history of seizures of > 3 days and/or impaired consciousness (GCS < or = 10), at the time of presentation to the hospital, constitute high risk. These cases must be identified promptly and aggressive therapy initiated in order to improve long term outcome.

Effects of L-cysteine and N-acetyl-L-cysteine on 4-hydroxy-2, 5-dimethyl-3(2H)-furanone (furaneol), 5-(hydroxymethyl)furfural, and 5-methylfurfural formation and browning in buffer solutions containing either rhamnose or glucose and arginine

Solutions of L-cysteine (Cys) and N-acetyl-L-cysteine (AcCys), containing glucose or rhamnose, with or without arginine, were buffered to pH 3, 5, and 7 and incubated at 70 degrees C for 48 h. Cys and AcCys inhibited the formation of (hydroxymethyl)furfural (HMF) from glucose and methylfurfural (MF) from rhamnose under acidic conditions. AcCys inhibited the accumulation of 4-hydroxy-2, 5-dimethyl- 3(2H)-furanone (DMHF, Furaneol) from rhamnose, but Cys, under our experimental conditions, enhanced Furaneol accumulation from rhamnose. Cys and AcCys reacted directly with Furaneol but not with HMF or MF. Both Cys and AcCys inhibited nonenzymatic browning at pH 7. At pH 3, however, Cys reacted with both glucose and rhamnose to produce unidentified compounds that increased the visible absorbency.

Solution conformations of deltorphin-I obtained from combined use of quantitative 2D-NMR and energy calculations: a comparison with dermenkephalin

Deltorphin-I, Tyr-D-Ala-Phe-Asp-Val-Val-Gly-NH2 and dermenkephalin, Tyr-D-Met-Phe-His-Leu-Met-Asp-NH2, two highly related opioid peptides from frog skin, display very similar N-termini but strikingly different C-terminal tails. Nevertheless, both peptides are highly potent at, and exquisitely selective for the delta-opioid receptor. To identify common determinants concuring to the remarkably efficient targeting of deltorphin-I and dermenkephalin, combined use of quantitative two-dimensional nuclear magnetic resonance (53 dipolar interactions studied at four temperatures) and energy calculations using simulated annealing generated five groups of deltorphin-I conformers. These groups were pooled into two families whose overall conformation could be described either by a left-handed helix (Family I) or by a big loop (Family II), both stabilized by H-bonds. Proximity of D-Ala2-Phe3-Asp4 and Val5-Val6-Gly7 triads is an obvious structural similarity between almost all groups in both families of structures. Whereas differences between the two families originated mostly from a transition at psi Asp4 backbone dihedral angle, the backbone structures at segment 1-4 are similar and spatial arrangements of Tyr1 (t) and Phe3 (g-) are identical in one group of each family. Moreover, these two groups have a N-terminal tetrapeptide whose conformation most closely resembles that of a well-defined group of structures for dermenkephalin. Altogether, these results suggest that conformational attributes that are common to dermenkephalin and deltorphin-I, i.e., the backbone conformation of the N-terminal tetrapeptide and preferential orientations in the side-chain of Tyr1 (t) and Phe3 (g-) underlie their ability to bind with high selectivity to the delta-opioid receptor.

Impaired responses to sweet taste in vitamin A-deficient rats

In brief-exposure, two-choice preference tests (sucrose solution v water), vitamin A-deficient (VAD) rats exhibited a decreased preference for sucrose relative to control rats. There was no difference in total fluid intake from both choices between the two groups, nor was any significant difference found in circumvallate taste papilla keratin size. It is concluded that the impaired preference for sucrose in VAD rats is due to a specific impairment in taste sensation rather than general malaise.