[IL-8 in experimental proliferative vitreoretiopathy induced by macrophages]

PURPOSE

To measure the concentration changes of IL-8 during the development of experimental proliferative vitreoretiopathy (PVR) induecd by macrophages and explore the effect on the inflammatory cells at the early stage of the model.

METHODS

Rabbit PVR model was induced by homogenous macrophages. The vitreous, agueous and vein blood were taken at different periods and IL-8 levels in them were measured with an ELISA kit.

RESULTS

The IL-8 level reached its peak of 1,325 pg/ml at 14th day in the model which was 14 times as the level of controls. The level then decreased to 48 pg/ml at 28th day after macrophage injection.

CONCLUSION

The changes of IL-8 in the model were parallel to the inflammatory reaction during the development of PVR, suggesting that IL-8 may play an important role the inflammatory cells' infiltrating and migrating to the vitreous.

[Antitumor effect on melanoma by in vivo direct injection of packaging cells transfected recombinant IL-2 gene]

Our previous studies showed that ex vivo transfer of human IL-2 gene into murine B16 melanoma cells resulted in the expression of IL-2 activity and had inhibitory effect on tumor growth in vivo. In this study, B16 melanoma bearing mice were injected directly with IL-2 recombinant PA317 cells. The in vivo gene transfer revealed significant reduction of tumor size and prolongation of survival of tumor bearing mice. Using slot blot analysis, the expression of IL-2 mRNA in tumor mass was detected and the IFN gamma activity was also enhanced in gene transferred mice. These results indicated that in vivo direct transfer of IL-2 recombinant retrovirual vector producing cells would induce transfer gene into tumor cells and exert its antitumor effect.

Vitrectomy for complicated Eales disease

PURPOSE

We determined the efficacy of pars plana vitrectomy in a series of patients with complicated Eales disease.

METHODS

Clinical records were reviewed on 47 consecutive patients (49 eyes) who underwent vitrectomy for persistent vitreous hemorrhage (PVH) and/or traction retinal detachment (TRD) with neovascular membranes (NVM). All cases were divided into 4 subgroups of eyes with PVH (without obvious NVM, n = 9), NVD (NVM from the optic disc, n = 10), NVP (peripheral NVM, n = 11), or ENV (extensive NVM and logn-standing TRD, n = 17).

RESULTS

The study included 8 women and 39 men with a mean age of 27.3 years (range, 16 to 50 years). The visual acuity was light perception in 15 eyes, hand motions in 18 eyes, counting fingers in 6 eyes and 0.02 to 0.1 in 10 eyes before vitrectomy. Visual acuity improved postoperatively in all eyes with PVH, NVD of NVP with a mean visual acuity of 0.32 (range, 0.05 to 1.0, n = 28) except 3 eyes unchanged. There was no significant difference (P > 0.05) in the patient age, preoperative visual acuity, or visual improvement after vitrectomy among these 3 subgroups. In the eyes with ENV, however, postoperative visual improvement was obtained but limited in 9 eyes (range, 0.02 to 0.15). Visual acuity was unchanged in 9 eyes. There was a significant difference (P < 0.01) in postoperative visual acuity between the eyes with ENV and the eyes with PVH, NVD or NVP.

CONCLUSIONS

Vitrectomy with removal of persistent vitreous hemorrhage and focal neovascular membranes and endolaser photocoagulation may lead to improved visual acuity in the majority of eyes with Eales disease. However, extensive fibrovascular membranes and long-standing retinal detachment result in poor visual outcome. Earlier surgery can be considered to prevent visual loss in the patients.

[ECG changes during [correction of dring] high G centrifuge training]

ECG of 47 healthy subjects, during G-training on the human centrifuge were recorded and analyzed. Training consisted of 4 G profiles and carried out in 6 d. Subjects were divided into 3 groups according to different anti-G equipment used. The results showed that: high incidence of arrhythmia (87%) was observed, and it increased with the increase of G level; subjects with R/S < 1 under +Gz environment, or HR sharply dropped immediately after the +Gz load have lower G-tolerance; incidence of arrhythmia is lower when advanced anti-G equipment was used.

[Exploratory vitrectomy for traumatized eyes with no light perception and dense vitreous hemorrhage]

OBJECTIVE

To evaluate the efficacy of exploratory vitrectomy for certain traumatized eyes with no light perception (NLP) and dense vitreous hemorrhage.

METHOD

We performed vitrectomy on 10 patients with NLP eyes after ocular trauma. Of them, eight had open globe injuries and two had closed blunt ocular trauma.

RESULTS

Postoperatively, six had visual acuities of light perception to 0.25 and four remained NLP. In most eyes, a potentially functional posterior retina and optic disc were observed during surgery.

CONCLUSION

Dense vitreous hemorrhage could be the most important factor for NLP after severe ocular trauma. Therefore, NLP does not always mean permanent loss of vision. Proper primary repair of the wound and timely vitrectomy may give a chance of visual recovery in selected traumatized eyes.

Comprehensive analysis of pharyngeal recurrence of laryngeal carcinoma after total laryngectomy

PURPOSE

This study analyzes the incidence, risk factors, treatment results, and prognosis of local recurrence at the pharynx after total laryngectomy for laryngeal carcinoma.

PATIENTS AND METHODS

The records of 292 patients who underwent total laryngectomy for the treatment of laryngeal carcinoma between January 1978 and December 1990 were reviewed.

RESULTS

Of these 292 patients, there were 24 patients who developed local recurrence at the pharynx. The 5-year actuarial cumulative local recurrence rate was 10%. There were 17 cases of pharyngeal recurrence alone, five cases of pharyngeal and nodal recurrence, one case of pharyngeal and tracheostomal recurrence, and one case of pharyngeal and distant metastasis. Ten (42%) patients were salvaged surgically; the 5-year actuarial survival rate after surgical salvage was 53%. The other 14 patients were treated with palliative treatment, and all died of tumor, with the longest period of survival being 28 months.

CONCLUSION

Surgical salvage of pharyngeal recurrence has acceptable results. Close monitoring of patients is important to have an early diagnosis of salvageable recurrence.

Relationship between some humoral factors and left ventricular hypertrophy in essential hypertension

OBJECTIVE

To evaluate the relationship between certain humoral factors and left ventricular hypertrophy (LVH) in essential hypertension.

PATIENTS AND METHODS

62 essential hypertension (EH) patients (32 men, 30 women; mean age, 55 years) and 20 normotensive healthy subjects (10 men, 10 women: mean age, 52 years) were studied. EH patients were divided into LVH group and non-LVH group by echocardiography. After an overnight fast, blood samples were taken for the determination of parathyroid hormone (PTH), angiotensin II (ATII) and aldosterone (ALD) by radioimmunoassay.

RESULTS

There was a significant difference in PTH. AT II and ALD between the EH group and control group. Furthermore, in LVH group PTH, ATII and ALD elevated significantly as compared with non-LVH group. In addition, we found that LVMI (left ventricular mass index) correlated with ATII (r = 0.342, P < 0.01) and ALD (r = 0.356, P < 0.01). There was a more significant correlation between LVMI and PTH (r = 0.422, P < 0.0025).

CONCLUSIONS

Some humoral factors are important determinants of LV mass. Besides the reninangiotensin-aldosterone system, PTH might play an important role in cardiac hypertrophy.

Improving American Indian Cancer Data in the Washington State Cancer Registry using linkages with the Indian Health Service and Tribal Records

BACKGROUND

Previous reports have suggested that American Indians are sometimes classified as other races on cancer registries. Also, cancer registries typically do not include data on tribal affiliation. This study determined the extent of racial misclassification of American Indians in the Washington State Cancer Registry (WSCR) and obtained tribal-specific cancer data for Washington State.

METHODS

A computer file including persons registered for services with the Portland Area Indian Health Service (IHS) or who were enrolled members of 19 tribes in Washington, Oregon, and Idaho (n = 127,375) was linked with WSCR records of incident cases for 1992 and 1993 (n = 49,420). Linkage was conducted with probabilistic methods using the AutoMatch software package.

RESULTS

Of 180 persons recorded as American Indian in the WSCR, 130 (72.2%) were identified in the IHS/tribal roll file. Of 259 American Indians included in the IHS/tribal file who were identified in the WSCR, 130 (50.2%) were classified as American Indian. The estimated age-adjusted cancer incidence among American Indians in Washington State increased from 153.5 per 100,000 population before record linkage to 267.5 per 100,000 after linkage. Of the 259 persons who were linked to the WSCR, 17 were not registered with IHS and appeared solely in the tribal rolls. Only two tribes had more than five identified cancer cases during the 2-year study period.

CONCLUSIONS

The number of IHS-enrolled American Indians or tribal members included in the WSCR would be underestimated by one third in the absence of record linkages, and the estimated cancer incidence of 43.6% would be lower before linkage. It is feasible to obtain tribal-specific cancer rates by linking tribal rolls to cancer registries, although the small number of cases in most tribes is a significant limitation. Further efforts to improve racial classification of American Indians in cancer registries should be undertaken.

Risk factors of tracheostomal recurrence after laryngectomy for laryngeal carcinoma

BACKGROUND

Tracheostomal recurrence after total laryngectomy for laryngeal carcinoma has a poor prognosis. The independent risk factors of tracheostomal recurrence are, however, not well documented.

METHODS

This is a multivariate analysis of the risk factors of tracheostomal recurrence after total laryngectomy for 322 laryngeal squamous cell carcinomas. The factors included in the analysis were sex, age, tumor stage, sites of tumor involvement, preoperative airway obstruction, preoperative tracheostomy, extent of surgical resection, radiotherapy, and pathological resection margin.

RESULTS

Seventeen (5%) patients developed tracheostomal recurrence. Univariate analysis showed that preoperative airway obstruction, subglottic involvement, and postcricoid extension were significant factors associated with tracheostomal recurrence. Multivariate analysis using logistic regression method showed that both subglottic and postcricoid involvement were independent predisposing factors for tracheostomal recurrence. The tracheostomal recurrence rates were 2% in patients without the risk factor and 10% in patients with the presence of one or both risk factors.

CONCLUSIONS

Subglottic and postcricoid involvement were independent risk factors for tracheostomal recurrence.

Synthesis and structure-activity relationships of 2-pyridones: a novel series of potent DNA gyrase inhibitors as antibacterial agents

Two novel series of 2-pyridones were synthesized by transposition of the nitrogen of 4-quinolones to the bridgehead position. This subtle interchange of the nitrogen atom with a carbon atom yielded two novel heterocyclic nuclei, pyrido[1,2-alpha]pyrimidine and quinolizine, which had not previously been evaluated as antibacterial agents and were found to be potent inhibitors of DNA gyrase. Quinolizines with a methyl group at the 9-position such as (S)-45a (ABT-719) demonstrate exceptional broad spectrum antibacterial activity. Most notably, they are active against resistant bacteria such as methicillin-resistant Staphylococcus aureus, vancomycin-resistant strains of enterococci, and ciprofloxacin-resistant organisms. In addition, 2-pyridones also possess favorable physiochemical and pharmacokinetic properties. These 2-pyridones were synthesized from the commercially available starting materials by 10-17 linear transformations. The structure of an adduct yielded by this sequence, (S)-45a (ABT-719), was determined by X-ray crystallographic analysis.

Primary closure of pharyngeal remnant after total laryngectomy and partial pharyngectomy: how much residual mucosa is sufficient?

After total laryngectomy with or without partial pharyngectomy, the remaining pharyngeal defect can be repaired either by primary closure or with additional tissue, depending on the amount of pharyngeal tissue remnant available. The aim of this study was to determine the minimum width of the pharyngeal remnant that could be safely closed primarily without causing difficulty in swallowing. A total of 52 consecutive patients who underwent total laryngectomy were entered into the study. The relaxed and stretched widths of the pharyngeal remnant were measured after removal of the specimen. The widths of the pharyngeal mucosa ranged from 1.5 to 5.0 cm relaxed (mean, 3.24 cm) and from 2.5 to 8.0 cm stretched (mean, 4.83 cm). All neopharynx was reconstructed by closing the pharynx primarily. Seven of the 52 patients developed recurrent tumor with concomitant dysphagia. Two of the 45 patients without recurrence presented with acute dysphagia from food bolus obstruction, and 1 patient developed benign inflammatory stricture following an episode of fish-bone impaction. The narrowest widths of the pharyngeal remnant in this group of 45 were 1.5 cm relaxed and 2.5 cm stretched. As these patients do not have swallowing difficulty, we conclude that in the absence of tumor recurrence, this amount of residual pharyngeal tissue is sufficient both for primary closure of the pharynx and in restoring swallowing function.

An immunohistochemical study of IgG, complement C3, collagen type III and macrophage-marker Ki-M7 in epiretinal membranes

PURPOSE

To observe the immunological changes in epiretinal membranes from the patients with proliferative vitreoretinopathy (PVR).

METHODS

Twelve samples of epiretinal membranes obtained during vitreous surgeries for PVR were examined by direct and indirect immunofluorescein histochemistry.

RESULTS

The cellular membranes in 8 cases were composed of retinal pigment epithelial cells, fibroblast-like cells, macrophages and collagen. Positive stainings of IgG, C3+ collagen type III and macrophage-marker Ki-M7 (CD68) was seen in the membranes.

CONCLUSION

The results indicate that humoral immune components and macrophages may play an important role in the development of epiretinal membrane formation.

[Promotion of c-fos oncogene expression in cultured rabbit lens epithelial cells by macrophages]

OBJECTIVE

This study was designed to test the hypothesis that inflammatory cells deposited on the surface of implanted intraocular lens stimulate the proliferation of residual lens epithelial cells.

METHODS

Immunocytochemical ABC methods with purified anti-human Fos protein serum antibody was used to stain the cultured rabbit lens epithelial cells incubated with rabbit macrophages and macrophage-conditioned medium (MCM).

RESULTS

The lens epithelial cell growth was faster in the cultures with macrophages and MCM than in the controls. Fos protein positive staining was found in the nuclei of epithelial cells cultured with macrophages for 4 hours, and of the cells with MCM for one hour; whereas the staining was negative in the cells of control cultures.

CONCLUSION

Macrophages promote c-fos oncogene expression in the lens epithelial cells, that might be mediated by bioactive factors secreted by macrophages.

Sensitive detection of selected cholinergic channel activators derivatized with 7-fluoro-4-nitrobenzo-2-oxa-1,3-diazole

A high-performance liquid chromatographic method with fluorescence detection was developed for a series of cholinergic channel activators using 7-fluoro-4-nitrobenzo-2-oxa-1,3-diazole (NBD-F) as a fluorescent labeling reagent. This method includes three separate steps: extraction of parent compound and internal standard with organic solvent from plasma, reaction of parent and internal standard in NBD-F precolumn to yield a fluorescent product and extraction of the resultant fluorophores with organic solvents. The extraction and reaction procedures were optimized for this series of structurally new compounds. The method showed high sensitivity, selectivity and reproducibility and proved useful for the determination of ng ml-1 plasma levels of selected cholinergic channel activators.

[Lens epithelial proliferation induced by macrophages after intraocular lens implantation in rabbits]

To approach the effect of intraocular lens implantation on the mechanism of posterior capsular opacification, the pathological changes of posterior lens capsule after intraocular lens implantation in rabbits were observed by transmission electron microscopy. The results were as follows: In the control group, 1 week after the operation and the injection of the medium of the macrophage suspension, the lens posterior capsule was covered by a layer of lens epithelium and until post-operative 6 months, the lens epithelium remained normal. In the experimental group, 1 week after the operation and the injection of the macrophage suspension into the anterior chamber, microfilaments appeared in the cytoplasm of lens epithelial cells, after 2 weeks, the lens epithelial cells produced collagen fibrils in the extracellular matrix and until postoperative 3 months, 2-3 layers of the lens epithelium proliferated in front of the posterior capsule and a large amount of collagenous fibers were formed around the cells. It is suggested that the macrophage promote the lens epithelial proliferation and the posterior capsular opacification.

Effect of perindopril and metoprolol on left ventricular hypertrophy and performance in essential hypertension

The effects of perindopril and metoprolol on left ventricular hypertrophy (LVH) and function were studied in 47 essential hypertensive patients with LVH. Previous antihypertensive drugs were discontinued for at least 2 weeks, after which patients were randomly divided into 2 groups. 25 subjects were treated with perindopril 4 to 8 mg once daily in the morning (Group A) and 22 subjects with metoprolol 25 to 62.5 mg twice daily (Group B). The subjects were evaluated before and after 4 and 8 weeks of treatment by use of echocardiography. Before treatment LV mass indexes (LVMI) of two groups were respectively 143.2 +/- 21.3 g/m2 and 140.6 +/- 23.7 g/m2 (P > 0.05). In Group A, reduction of LVMI occurred after 4 weeks of treatment, and more pronounced after 8 weeks (from 143.2 +/- 21.3 g/m2 to 126.6 +/- 15.3 g/m2, P < 0.001), whereas reduction of LVMI occurred only after 8 weeks in Group B (from 140.6 +/- 23.7 g/m2 to 133.4 +/- 13.2 g/m2, P < 0.001). In addition, there was a significant (P < 0.05) difference in LVMI between the two groups after 8 weeks. LV systolic function remained unchanged, whereas E/A increased significantly (P < 0.001) in two groups after 8 weeks. In conclusion, antihypertensive treatment with perindopril and metoprolol induced a significant regression of LVH associated with improvement in LV diastolic performance. Perindopril, compared with metoprolol, was more effective in reversing LVH.

mRNA expression of vimentin gene in lens of transgenic mouse and DNA amplification in human cataracts

PURPOSE

To investigate the role of vimentin gene in cataractogenesis.

METHODS

The 12.7kb chicken vimentin genes were microinjected into the male pronuclei of 918 fertilized mice eggs. 841 injected embryos were transferred into oviducts of pseudopregnant recipient females, of which 12 pregnant mice gave birth to 49 offspring mice. The integration and expression of exogenous gene in the offspring were analysed by Southern and Northern blot hybridizations. In the human senile cataract, the lens vimentin gene was analyzed with the chicken vimentin gene probe.

RESULTS

It showed that four of F1 offspring were transgenic mice in which the chicken vimentin gene was integrated in their genomes. The transgenic band was 12kb, similar to the 12.7kb chicken vimentin fragment injected. One 2kb vimentin mRNA was visualized on E2 mouse lens blot, which revealed that the chicken vimentin gene was efficiently expressed in this transgenic mouse. In the human senile cataract lens, 12kb BamHI-restricted vimentin fragments displayed a stronger hybridization signal than that of the control lens in Southern blot analysis. It implies that the formation of human senile cataract may be associated with the amplification of vimentin gene.

CONCLUSIONS

We have successfully developed four transgenic mice bearing chicken vimentin gene and having mRNA expression which can be used for further study. It is to be observed if the normal lens cell function is affected by the expressed product and cataract occurs in our transgenic mice. The cause of the gene amplification in human cataract remains for further investigation.

[The influence of macrophage on the rates of cultured rabbit lens epithelial cell proliferation and DNA synthesis]

Cell and H3-TDR liquid scintillation countings were adopted to investigate the influence of macrophage on the proliferative rate of cultured rabbit lens epithelial cells, in vitro. After 24 hours of the action of macrophage opsonic fluid on the cell culture, the rates of cell proliferation and DNA synthesis in the experimental group were higher than those of the control group (P < 0.05) and maintained so to the fifth day. It is demonstrated that the macrophage and its active factors can promote the proliferation of the lens epithelial cells, that is possibly related to the posterior capsular opacification after extracapsular cataract extraction.

Sinusitis in patients with cystic fibrosis

The management of sinus disease in children with cystic fibrosis is reviewed, based on a literature review and clinical experience in The Hospital for Sick Children, Toronto. Diagnostic and treatment approaches are discussed, with emphasis given to indications for surgical therapies. Great importance is given to the preservation of normal nasal anatomy whenever possible to minimize the possibility of iatrogenic injuries occurring, especially when revision surgery is required.

Laser aryepiglottoplasty for the treatment of neurasthenic laryngomalacia in cerebral palsy

Patients with cerebral palsy usually suffer from lack of coordination in the neuromuscular mechanism in their upper airway and digestive tract. Difficulty in swallowing and aspiration are common problems in these patients, and stridorous breathing sometimes develops as a secondary symptom. Laryngoscopic examination revealed that redundant tissue in the aryepiglottic fold area was the cause of stridor and upper airway obstruction in four patients with cerebral palsy. We report on these four patients in whom laser reduction of the redundant mucosa led to dramatic improvements in stridor. Secondary benefits to family members and others were equally impressive.

[Influence of radioimmunoimaging on the survival rate of ovarian carcinoma patients]

Two groups of patients suffered from ovarian carcinoma were studied retrospectively after similar treatments; in one group of 22 patients radioimmunoimaging (RII) had been used, which was not used in the other group of 15 patients. Other factors were similar in the two group such as hospitalization period, courses of surgical treatment and regimes of chemotherapy after surgery. The staging according to FIGO was also similar in the two groups except that the number of patients in stage III was 14 in the RII group but 8 in the non-RII group. Neither the age distribution nor the histopathological diagnosis was of much difference. 131I labeled monoclonal antibody against ovarian serous adenocarcinoma, generated in our laboratory, was given to all patients intraperitoneally either before or after the surgery; 7 cases before the initial operation, 9 cases before the second look operation and 6 cases for follow up after surgery and chemotherapy. The death rates of stage III were 42.9% and 75.0% in the RII group and non-RII group respectively. By means of Kaplain Meir's life table calculation the 3 year survival rates for the two groups were 63.5% and 25.0% respectively. The RII group was obviously higher than the non-RII group even though not statistically significant. These results were similar to those reported in the literature. Three very late cases of ovarian carcinoma were reported, in whom RII had been used, are still living after follow-up for more than 5 years. The beneficial role of induction of the idiotypic network was discussed, and the possibility of innoculation is under investigation.

[mRNA expression of vimentin gene in lens of transgenic mouse and DNA amplification in human cataract]

To investigate the role of vimentin gene in cataractogenesis, 12.7 Kb chicken vimentin genes were microinjected into the male pronuclei of 530 fertilized mouse eggs. 453 injected embryos were transferred into the oviducts of 18 pseudopregnant recipient females, of which 9 pregnant mice gave births to 37 offspring mice. The integration and expression of exogenous gene in the offsprings were analyzed by Southern and Northern blot hybridizations. It is shown that the E2 offspring was a transgenic mouse in which the chicken vimentin gene was integrated in its genome and efficiently expressed in mRNA level in its lens. In the human senile cataract lens, Bam-HI-restricted vimentin fragments displayed a stronger hybridization signal than that of the control lens in Southern blot analysis.

Congenital nasal pyriform aperture stenosis as a presenting feature of holoprosencephaly

Congenital nasal pyriform apertures stenosis (CNPAS), a recently recognized uncommon cause of nasal airway obstruction, can be a life-threatening circumstance in the neonate. This study's experience with six cases confirmed the suggestion that CNPAS represents a manifestation of holoprosencephaly. Management of this condition depends firstly on the overall prognosis of the patient and secondly the severity of obstruction. Patients with poor overall prognosis should be managed conservatively with an oropharyngeal airway. In patients with a good outlook, the choice of treatment is conservative for those with less severe obstruction and surgical correction for those with complete obstruction. The ability to pass a No. 5Fr catheter (O.D. 1.67 mm) may be a guide to the choice of treatment. An increase in awareness among otolaryngologists on the nature of CNPAS is necessary to improve overall management of such patients.

Comments on "Data truncation artifact reduction in MR imaging using a multilayer neural network"

A recent paper by Yan and Mao (see ibid., vol.12, no.1, p.73-7, 1993) provided the results of using a neural network based nonlinear prediction algorithm to extrapolate truncated magnetic resonance data. The extrapolation is intended to reduce the truncation artifacts that result when reconstructing an image from a limited k-space magnetic resonance data set using the discrete Fourier transform. When attempting to quantitatively compare Yan and Mao's method with the authors' own existing constrained modeling algorithm, the authors discovered a systematic error in Yan and Mao's analysis. With the error corrected, it was found that Yan and Mao's approach worked significantly better than they have reported and was more stable in the presence of noise.

Ofloxacin eardrop treatment for active chronic suppurative otitis media: prospective randomized study

This report presents a prospective randomized study of 0.3 percent ofloxacin eardrops for the treatment of active chronic suppurative otitis media. Twenty-nine patients were treated with ofloxacin eardrops for 1 week, and another 27 patients were treated with Augmentin for 1 week. One week after completion of treatment, 22 (76%) patients of the group treated with ofloxacin had dry ears, and only seven (26%) patients treated with Augmentin had dry ears. Ofloxacin eardrops were effective in the initial treatment of active chronic suppurative otitis media.

[Amniotic fluid C-peptide in pregnancy with diabetes]

A prospective study on amniotic fluid C-peptide (AFCP) was made in 29 women with diabetic pregnancy and 23 non-diabetic control subjects. The mean concentrations of AFCP were found to be significantly higher in diabetic pregnancy than in non-diabetic pregnancy (P < 0.01) (diabetic group AFCP 1.89 +/- 1.53ng/ml; control group 0.88 +/- 0.51ng/ml). AFCP levels were related to the degree of blood glucose control during pregnancy and not to diabetic classification. The results show that fetal hyperinsulinemia reduced in these women that the achieved metabolic control of maternal blood glucose levels approached normal values. A higher neonatal complications occurred while AFCP was over 1.68ng/ml.

Photoperiod regulates the LH response to central glutamatergic stimulation in the male Syrian hamster

This study investigated central glutamatergic function in relation to photoperiodically-induced changes in the secretion of luteinizing hormone (LH). The experimental approach was to compare the central effects of glutamate agonists on LH secretion in reproductively active hamsters kept in long days (LD) with those in photoinhibited hamsters kept in short days (SD) for 6 weeks and having regressed testes. Agonists were delivered via a cannula into the III ventricle of freely moving hamsters, and blood samples collected 10 to 15 min after the start of the infusion. A high dose (3.0 nmole) of N-methyl-D-L-aspartate (NMDA) induced significant (P<0.01) increases in serum concentrations of LH in hamsters in both photoperiods, though the NMDA-induced increase relative to endogenous LH concentrations was greater in SD than in LD. However, a lower dose of NMDA (0.3 nmole revealed a difference in sensitivity. This dose significantly increased serum LH (P<0.05) in hamsters in SD but had no effect in those in LD. The seasonal difference in response to NMDA was compared with the response to an equimolar dose of alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA), a non-NMDA agonist. This dose of AMPA (0.3 nmole) induced a two-fold increase (P<0.05) in serum concentrations of LH in hamsters in both photoperiods, relative to vehicle-treated controls. In a third experiment the dose-response effects of central AMPA on LH secretion were examined more closely. The sensitivity of LH secretion to stimulation with AMPA did not differ between SD- and LD-housed hamsters. Thus the photoperiod-related difference in sensitivity to stimulation with glutamate agonists is specific for NMDA receptor-mediated activation, rather than a passive reflection of differences in the capacity to secrete GnRH/LH in SD and LD photoperiods. To investigate the site of action of NMDA, the expression of the c-fos immediate-early gene, as assessed by immunocytochemistry for its protein product Fos, was used as a marker of neuronal activation, because previous studies in rodents indicate that a high proportion of GnRH neurons express c-fos at the time of the mid-cycle LH surge. NMDA induced widespread expression of c-fos in many periventricular regions including the medial preoptic area (POA) and ventromedial hypothalamic nucleus. However, dual ICC revealed that in neither photoperiod was Fos present in GnRH-positive neurons 1 h after infusion of 3 nmole of NMDA, despite the increases in LH secretion induced by the infusion. AMPA injected icv at doses which released LH did not enhance expression of c-fos in the hypothalamus. Thus, in the male, enhanced expression of c-fos cannot be detected in GnRH neurons at the time of increased secretion of this hormone induced by glutamate agonists. In conclusion, these results show that both NMDA and non-NMDA glutamatergic pathways potentially regulated LH secretion in the Syrian hamster. The increased sensitivity to NMDA but unaltered sensitivity to AMPA in photoinhibited hamsters in SD is consistent with the view that changes in photoperiod might induce specific alterations in NMDA-mediated pathways that ultimately regulate GnRH neurosecretory activity.

Crystallization and preliminary crystallographic data for formyltetrahydrofolate synthetase from Clostridium thermoaceticum

Formyltetrahydrofolate synthetase from Clostridium thermoaceticum has been crystallized using the hanging-drop method from ammonium sulphate and PEG solutions. Crystals are trigonal, the space group is R32, a = 163 A, c = 259 A. A 4.2 A resolution data set has been collected. Analysis of the data using the self-rotation function shows that tetramers have approximate 222 symmetry and are positioned on a crystallographic 2-fold axis.

Early changes of auditory brain stem evoked response after radiotherapy for nasopharyngeal carcinoma--a prospective study

A prospective study of the effect of radiotherapy for nasopharyngeal carcinoma on hearing was carried out on 49 patients who had pure tone, impedance audiometry and auditory brain stem evoked response (ABR) recordings before, immediately, three, six and 12 months after radiotherapy. Fourteen patients complained of intermittent tinnitus after radiotherapy. We found that 11 initially normal ears of nine patients developed a middle ear effusion, three to six months after radiotherapy. There was mixed sensorineural and conductive hearing impairment after radiotherapy. Persistent impairment of ABR was detected immediately after completion of radiotherapy. The waves I-III and I-V interpeak latency intervals were significantly prolonged one year after radiotherapy. The study shows that radiotherapy for nasopharyngeal carcinoma impairs hearing by acting on the middle ear, the cochlea and the brain stem auditory pathway.

Photoperiodic regulation of glutamatergic stimulation of secretion of luteinizing hormone in male Syrian hamsters

It has been suggested that changes in endogenous glutamatergic stimulation of secretion of luteinizing hormone (LH) induced by photoperiod play a role in regulating seasonal cycles of reproductive activity. The aim of this study was to test the hypothesis that the glutamatergic control of the secretion of LH in the male Syrian hamster is sensitive to photoperiod, by determining whether the glutamate agonist N-methyl-D-aspartate (NMDA) could stimulate LH secretion in this species and, if so, to determine whether the response varied among animals exposed to different daylengths. In the first experiment, adult male hamsters were housed in either short day (8 h light: 16 h dark) for 6 weeks to induce testicular regression, or long days (16 h light: 8 h dark) to maintain testicular function, and the effects of systemic administration of NMDA on serum LH concentrations were determined. In the short-day hamsters, all s.c. doses of NMDA (25-75 mg kg-1 body weight) produced a robust rise in serum LH concentrations within 15 min. In the long-day hamsters, basal LH concentrations were higher than in short-day hamsters, but only the highest dose of NMDA produced a significant increase in LH concentrations, and the magnitude of this increment was less than those observed in short days. In hamsters in long days, the low doses of NMDA that did not significantly alter LH concentrations nevertheless significantly suppressed serum prolactin concentrations, demonstrating the efficacy of the drug. In hamsters in short days, serum prolactin concentrations were at the limit of detection of the assay, so no inhibitory effect of NMDA on prolactin secretion could be determined on this photoperiod. In the second experiment, the effects of a fixed dose of NMDA (50 mg kg-1 body weight) was tested at intervals in hamsters exposed to short days for a prolonged period such that their testes initially regressed, but then became scotorefractory and testicular recrudescence occurred. After 6 and 12 weeks in short days, NMDA stimulated LH secretion. However, after 24 weeks in short days when testicular recrudescence was complete, the response to NMDA was lost. A third experiment determined whether the reduced response to NMDA in hamsters on long days relative to those in short days might result from higher concentrations of circulating testosterone. Hamsters in long days were castrated to remove the influence of gonadal feedback, and the response to NMDA tested 3 weeks later when endogenous LH concentrations had risen to levels characteristic of the chronically castrated condition.(ABSTRACT TRUNCATED AT 400 WORDS)

Effect of irradiation on middle ear effusion due to nasopharyngeal carcinoma

The management of middle ear effusion by myringotomy and insertion of ventilation tubes in 75 adult patients was evaluated. In Group 1 the middle ear effusion was not related to nasopharyngeal carcinoma. The patients with nasopharyngeal carcinoma were subdivided into pre and post-radiotherapy groups (Group 2 and Group 3) according to the time of insertion of the ventilation tubes. Myringotomy and insertion of ventilation tubes achieved significant hearing gain in all three groups. The pre and post-radiotherapy groups had a higher post-operative infection rate than Group 1 (P greater than 0.01). The duration of a persistent tympanic membrane defect in the post-radiotherapy group was significantly longer than Group 1 (P = 0.03). The post-radiotherapy group had more perforations than Group 1 (P = 0.02). A total of 28% of ears in the post-radiotherapy group were discharging at the last visit. In view of the higher complication rate in the post-radiotherapy group, the role of myringotomy and insertion of ventilation tube is reassessed.

Design and testing of a functional group-specific DNA probe for the study of natural populations of acetogenic bacteria

The acetogens, although phylogenetically diverse, can be characterized by their possession of the acetyl coenzyme A (acetyl-CoA) pathway for autotrophic CO2 fixation. The gene encoding formyltetrahydrofolate synthetase, a key enzyme of the acetyl-CoA pathway, was previously cloned from the thermophilic acetogen Clostridium thermoaceticum and has now been tested as a group-specific probe for acetogens. Stable hybrids were formed between the probe and single DNA fragments from eight known acetogens representing six genera. A hybrid was also formed between the probe and a DNA fragment from one sulfate reducer known to be capable of both autotrophic CO2 fixation and acetate catabolism. No such hybrid was formed between the probe and DNA from a homoacetate fermenter not known to use the acetyl-CoA pathway, with two known formyltetrahydrofolate synthetase-producing purine fermenters, or with DNA from 27 other species representing 16 genera of organisms that do not use the acetyl-CoA pathway. DNA purified from cells extracted from horse manure was also screened with the acetogen probe. Six hybrids, indicating at least six detectable acetogen "strains," were observed.

The role of the fibreoptic bronchoscope in otorhinolaryngological practice

Flexible fibreoptic bronchoscope has been employed in the examination of the nasopharynx, pharynx, larynx, trachea, bronchus and intrathoracic oesophagus under local anaesthesia. It is used either for diagnostic or therapeutic purposes. A total of 1690 procedures have been performed with no complication. The indications and findings in these procedures are listed. The advantages and limitations of the use of flexible fibreoptic bronchoscope as a 'panendoscopic examination' instrument are discussed.

Photochemical reactions in organized assemblies. 40. Amylose and carboxymethylamylose inclusion complexes with photoreactive molecules

This paper focuses on a study of unimolecular and bimolecular photoreactions occurring with reactants which can be incorporated into the linear polysugars amylose and carboxymethylamylose. Hydrophobic and surfactant trans (E) stilbene derivatives form complexes in which the stilbene chromophore shows enhanced fluorescence and reduced trans → cis isomerization efficiencies. The reactivity of the excited surfactant–stilbene singlet towards the quencher iodide ion has been compared in water/dimethylsulfoxide in the presence and absence of amylose under conditions where complex formation is nearly complete. Some relatively hydrophobic viologen dications have also been found to form complexes with the water soluble carboxymethylamylose. Although the dications complex relatively weakly, the partially reduced monocations complex more strongly. This results in selective retardation of back electron transfer rates when the viologens are used as electron transfer quencher-oxidants for certain luminescent ruthenium polypyridine complexes.