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Bronchoalveolar lavage (BAL) studies in 20 patients at Bhopal, 1.3 +/- 0.4 yr and 2.7 +/- 0.6 yr after toxic gas exposure had revealed that the lower respiratory tract inflammation had progressed from initial macrophage alveolitis to macrophage-neutrophilic alveolitis. The interval between the two lavages was 1.4 +/- 0.6 yr. BAL studies in a new group of 24 patients 5.1 +/- 1.0 yr after exposure had confirmed chronic inflammation of the lower respiratory tract as evidenced by macrophage-neutrophilic alveolitis in these subjects as well. Clinical, radiographic and pulmonary function abnormalities were persistent in a proportion of subjects in both groups. Fibronectin (FN) levels were estimated in BAL fluid in 41 patients. Elevated FN levels were seen in 12 (29.3%) subjects and nine of these 12 had radiographic abnormalities. Severely exposed subjects (n = 30) had significantly higher BAL fibronectin levels compared to normal subjects and mild/moderately exposed subjects. Repeat FN estimations in BAL samples from 10 patients had revealed that five had abnormally high FN including three who had high FN on both occasions. The number of patients showing abnormal decline in pulmonary function was higher in patients with elevated FN than in patients with normal FN. Thus, persisting clinical, roentgenographic and ventilatory abnormalities, as well as macrophage-neutrophilic alveolitis along with abnormally elevated FN levels in a proportion of subjects, suggest the possibility that lung fibrosis can occur in subjects exposed to toxic gas at Bhopal.

We wanted to determine the procoagulant activity (PCA) of bronchoalveolar lavage fluids, in order to understand the macrophage-mediated lung injury at the site of tuberculous lesion. Alveolar lavage fluids taken from the site of a lesion (radiologically abnormal site (RAS)) and an unaffected site (radiologically normal site (RNS)) of active pulmonary tuberculosis (TB) patients (n = 7) and inactive (cured) patients (n = 9) were studied for their PCA producing potential. The observed results were not significant using Mann-Whitney test, and thus all increases/decreases reported below are trends/tendencies only. An increased PCA was seen in 4 out of 7 cell-free lavage supernatants of active-TB taken from the site of lesion (RAS), compared to only 1 out of 9 in inactive-TB. The PCA producing potential of the alveolar macrophages of RAS and RNS of active-TB patients was enhanced when the alveolar macrophages were co-cultured with autologous peripheral blood lymphocytes under in vitro condition. Stimulation with purified protein derivative (PPD) of M. tuberculosis showed a variable (increased or decreased) PCA production. Peripheral blood monocytes and total mononuclear cells (monocytes+lymphocytes) of active-TB patients stimulated with or without PPD showed increased PCA production, compared with normal individuals and inactive-TB patients. The present study suggests that increased production of PCA by the alveolar macrophages, in collaboration with lymphocytes and other cells at the site of tuberculous lesions will result in fibrin formation. The deposition of fibrin in the alveoli may lead to further lung injury.

We wished to evaluate the pulmonary defence capacity against common bacterial infections in patients with pulmonary tuberculosis. Bactericidal activity against Staphylococcus aureus of bronchoalveolar lavage fluids (cell-free supernatants) of patients with active (n = 13) and inactive pulmonary tuberculosis (n = 8), and normal individuals (n = 6), were studied. The 2 and 4 h bactericidal activities were higher than the 0 h activity in lavage fluids of healthy subjects and patients with inactive pulmonary tuberculosis. Active tuberculous lavage fluids were equally competent in their bactericidal activity against S. aureus at 0 and 2 h, but a reduced S. aureus killing was seen at 4 h of incubation. Estimation of total phospholipid levels revealed no significant difference between the various lavage fluids. This reduced killing of S. aureus showed a relationship with the cellular components (lymphocytes and macrophages) of active tuberculous lavage fluids. A reduced killing was associated with no lymphocytic alveolitis, and an increased killing with lymphocytic alveolitis. This study suggests that alveolar lining material of patients with active pulmonary tuberculosis has less bactericidal activity against bacterial infections, such as S. aureus.

Maximal Expiratory Flow Rates such as Peak Expiratory Flow Rate (PEFR), rates at 25%, 50% and 75% of forced vital capacity (V max 25%, V max 50% and V max 75%) and forced expiratory flow during the middle half of forced vital capacity (FEF 25-75%) were measured in 273 healthy non-smoking adults (144 males, 129 females) aged 15-63 years living in Madras. Regression equations were derived for men and women for predicting maximal expiratory flow rates for adults in South India. Expiratory Flow Rates at lower lung volumes in men were similar to those reported for caucasians, but higher than those reported for western Indian Subjects. However, in women the flow rates were similar to those of western Indians and lower than those of caucasians, probably due to indoor air pollution since childhood. These data may suggest that expiratory flow rates at lower lung volumes may not show ethnic variability.

Maximal expiratory flow rates such as peak expiratory flow rate (PEFR), rates at 25%, 50% and 75% of vital capacity (VE max 25%, VE max 50%, VE max 75%) and forced expiratory flow during the middle half of forced vital capacity (FEF 25-75%) were recorded in 23 patients with tropical eosinophilia (TE) before and after treatment. The mean values of all flow rates were significantly lower (P < 0.001) in untreated TE patients compared to predicted values. After three weeks' treatment with diethylcarbamazine, although there was a significant rise in the mean values of all expiratory flow rates (P < 0.05) except VE max 75% (P > 0.2), all flow rates continued to be significantly lower (P < 0.01) at one month than predicted values.

Maximal voluntary ventilation (MVV) was measured in 256 healthy non-smoking adults (132 males, 124 females) aged 15-63 years living in Madras. The mean MVV (+/- SD) in males was 126.7 +/- 31.9 and in females 77.7 +/- 16.4. Regression equations were derived for men and women for predicting maximal voluntary ventilation for adults in South India. MVV in South Indians were similar to those reported for other Indian subjects, but lower than those reported for caucasians.

A previously unreported example of perineuronal satellitosis in the medial CA1 and adjacent subiculum in the human hippocampal formation is described. This phenomenon is characterized by a clustering of glial cells in relation to the perikarya of a subpopulation of neurons in the deep pyramidal layer and around most neurons scattered in the stratum oriens and subcortical white matter. Most of the perineuronal satellite glia were identified as oligodendrocytes based on their nuclear chromatin patterns and antigenic properties. Satellite oligodendrocytes were mostly of the medium dense variety. A type of satellite glia with nuclear features of the dark oligodendrocyte could not be identified unequivocally using the antigenic criteria employed in this study.

Red cell membranes were isolated from blood samples obtained from athletes during exhaustive exercise on a bicycle ergometer and during the subsequent recovery period of 60 min. Plasma lactate levels were also determined. During exercise, cell membranes were progressively depleted of cholesterol and, at exhaustion, membrane cholesterol was less than 80% of the initial level. A parallel decline in Na+,K(+)-ATPase was also noted, while phospholipid reduction was around 5%. During recovery, the erythrocyte membrane cholesterol and Na+,K(+)-ATPase increased, but at a slow rate and were inversely proportional to plasma lactate content.

Three radiologically and bacteriologically confirmed pulmonary tuberculosis patients had eosinophilic pneumonia, as demonstrated by BAL. In two patients, pulmonary eosinophilia was present only at the site of the lesion and the third had eosinophilia in both peripheral blood and lung. There was complete elimination of the eosinophilic inflammatory process in two patients who had successfully completed antituberculosis treatment.

The presence of extracellular matrix protein fibronectin (FN) at the site of neural trauma was examined using immunohistochemical methods. At 2, 4 and 7 days following a penetrating wound through the rat cerebral cortex, FN staining was detected in the neuropil and in non-neuronal cells adjacent to the wound. FN-stained cells were GFAP-negative and were identified as brain macrophages based on cell surface staining for CR3 complement receptor. Our findings suggest a role for FN in the repair of neural trauma.

Forty-one patients with untreated tropical pulmonary eosinophilia (TPE) were studied to determine whether there was any relationship between lower respiratory tract inflammation and either changes in lung function or abnormalities in chest roentgenograms. Total number of inflammatory cells in bronchoalveolar lavage (BAL) fluid, consisting of alveolar macrophages, lymphocytes, eosinophils and neutrophils had significant negative correlations with transfer factor (TLCO) (r = 0.519, p less than 0.001), transfer coefficient (KCO) (r = 0.312, p less than 0.05) and total lung capacity (TLC) (r = 0.352, p less than 0.05). The absolute count of eosinophils in BAL fluid had a significant negative correlation with TLCO (r = 0.430, p less than 0.01) and KCO (r = 0.300, p = 0.05), but not with forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1) or TLC. However, the absolute count of alveolar macrophages had a significant negative correlation with FVC (r = 0.343, p less than 0.05), FEV1 (r = 0.341, p less than 0.05) and TLC (r = 0.305, p less than 0.05), but not with TLCO or KCO. The total number of lymphocytes had a negative correlation with TLC (r = 0.315, p less than 0.05). There was no correlation between the types of cells recovered in BAL fluid and changes in chest radiographs as assessed by the ILO classification for occupational lung diseases. These data suggest that there may be a dissociation of pulmonary pathophysiological changes produced by different inflammatory cells in the lower respiratory tract. Macrophages and lymphocytes may produce more harm to the lung, as evidenced by significant negative correlations of these cells with lung volumes.

In Alzheimer's disease (AD), neuritic plaques are often found in the hippocampal dentate gyrus along the boundary between inner and outer molecular layers. The dentate outer molecular layer in AD also exhibits axon sprouting in response to an early loss of entorhinal neurons. The relationship between the laminar arrangement of plaques and the sprouting remains unclear. In experimental entorhinal lesions in the rat, the denervated dentate outer molecular layer demonstrates hypertrophic astrocytes which may provide trophic support for the sprouting response. It is not known whether an equivalent astrocyte response occurs in AD or whether this response is related to the distribution of plaques. We used immunohistochemical staining for glial fibrillary acidic protein (GFAP) to demonstrate reactive astrocytes in the hippocampus in AD patients and age-matched controls. These results were compared to the astrocyte response to an experimental entorhinal lesion in the rat. Quantitative and qualitative analyses demonstrated a significant increase in GFAP-positive hypertrophic astrocytes in the dentate outer molecular layer in AD compared to controls. These astrocytes were randomly distributed within the outer layer and did not parallel the distribution of neuritic plaques. In the entorhinal-lesioned rat, reactive hypertrophied astrocytes also showed a selective distribution within the denervated outer molecular layer. Our results further support the similarity of the hippocampal response in AD and experimental entorhinal lesion but do not explain the laminar distribution of neuritic plaques along the denervated zone.

Sequential immunocytochemical double labeling of glial fibrillary acidic protein (GFAP) and transferrin (Tf) was used for the simultaneous identification of astrocytes and oligodendrocytes in paraffin-embedded sections of the rat brain. Paraformaldehyde or formalin-alcohol-acetic acid fixation followed by protease treatment of paraffin-embedded sections provided the most satisfactory double-labeling. The results demonstrated GFAP-positive astrocytes and Tf-positive oligodendrocytes as two subpopulations of glia with no overlap. Our results suggest that, with some exceptions, immunocytochemical double labeling of GFAP and Tf has a potential application for the simultaneous identification of astrocytes and oligodendrocytes in the rat brain.

Bronchoalveolar lavage studies in 33 patients with acute untreated tropical eosinophilia have demonstrated intense eosinophilic alveolitis. Following treatment with a standard 3-week course of diethylcarbamazine, there was a significant fall in lung eosinophils (p less than 0.001). However, a mild alveolitis characterised by hypercellular lavage fluid due to a significant increase in absolute alveolar macrophages (p less than 0.001) and due to an increase in both the absolute number (p less than 0.01) and percentage of eosinophils (p = 0.02) was persisting at 1 month despite treatment. Long-term follow-up is essential to know the fate of alveolitis.

Fifty patients with tropical eosinophilia were studied clinically and physiologically, before and after a standard 3-week course of diethylcarbamazine. Before treatment the main physiological abnormality was a reduction in the carbon monoxide transfer factor. One month after the start of treatment most patients had shown a marked symptomatic improvement, but peripheral blood eosinophilia persisted in 52%, radiographic abnormalities in 44%, cough in 22% and chest signs in 8%. Significant improvement was noted in almost all aspects of lung function including blood gases, but the mean values for forced expiratory volume in one second, forced vital capacity, transfer factor and transfer coefficient continued to be significantly lower than predicted values. This study demonstrates the incomplete reversal of clinical, haematological, radiological and physiological changes in tropical eosinophilia one month after starting a 3-week course of diethylcarbamazine.

A controlled study of three short-course regimens was undertaken in South Indian patients with newly diagnosed, sputum-positive pulmonary tuberculosis. The patients were allocated at random to one of three regimens: a) Rifampicin, streptomycin, isoniazid and pyrazinamide daily for 3 months (R3); b) the same regimen as above but followed by streptomycin, isoniazid and pyrazinamide twice-weekly for a further period of 2 months (R5); c) the same as R5 but without rifampicin (Z5). A bacteriological relapse requiring treatment occurred by 5 years in 16.8% of 113 R3, 5.2% of 97 R5, and 20.0% of 115 Z5 patients with organisms sensitive to streptomycin and isoniazid initially. The differences in the relapse rates between the R3 and R5 regimens and the R5 and Z5 regimens were statistically significant (p less than 0.01 for both). Considering patients with organisms initially resistant to streptomycin or isoniazid or both, 7 of 52 patients (4 R3, 2 R5, 1 Z5) had a bacteriological relapse requiring retreatment.

An antibody specific for the predicted carboxyterminal sequence of the human brain isozyme of glycogen phosphorylase (alpha-1,4-D-glucan:orthophosphate D-glucosyltransferase, EC 2.4.1.1) was generated to verify the carboxyterminal amino acid sequence of this protein. The isozyme-specific antibody was used to examine the localization of this protein in primate and non-primate brain. The highest levels of the brain isozyme in cerebrum and cerebellum were found in fibrous astrocytes, many with glial processes that appear to terminate upon blood vessels.

Objective: To assess the efficacy of a short course chemotherapy regimen for treating tuberculosis of the lymph nodes in children., Design: Open, collaborative, outpatient clinical trial., Setting: Outpatient department of the Tuberculosis Research Centre, paediatric surgery departments of the Institute of Child Health and Hospital for Children and the Government Stanley Hospital, Madras, South India., Patients: Children aged 1-12 years with extensive, multiple site, superficial tuberculous lymphadenitis confirmed by biopsy (histopathology or culture)., Interventions: Patients were treated with a fully supervised intermittent chemotherapy regimen consisting of streptomycin, rifampicin, isoniazid, and pyrazinamide three times a week for two months followed by streptomycin and isoniazid twice a week for four months on an outpatient basis. Surgery was limited to biopsy of nodes for diagnosis and assessment., Main Outcome Measures: Response to chemotherapy was assessed by regression of lymph nodes and healing of sinuses and abscesses during treatment and follow up. Compliance with treatment and frequency of adverse reactions were also estimated., Results: 197 Patients were admitted to the study and 168 into the analysis. The regimen was well tolerated and compliance was good with 101 (60%) patients receiving the prescribed chemotherapy within 15 days of the stipulated period of six months. Those whose chemotherapy extended beyond that period received the same total number of doses. Clinical response was favourable in most patients at the end of treatment. Sinuses and abscesses healed rapidly. Residual lymphadenopathy (exceeding 10 mm diameter) was present in 50 (30%) patients at the end of treatment; these nodes were biopsied. Fresh nodes, increase in size of nodes, and sinuses and abscesses occurred both during treatment and follow up. After 36 months of follow up after treatment only 5 (3%) patients required retreatment for tuberculosis., Conclusion: Tuberculous lymphadenitis in children can be successfully treated with a short course chemotherapy regimen of six months.

A critical issue for clinical and research applications of transplant techniques is the long-term survival of transplanted tissue and its effect on the host brain. In this study, entorhinal cortices from donor embryos were transplanted into the lesioned angular bundle of juvenile male Sprague-Dawley rats. Animals were maintained for 2 years and then sacrificed for histological and histochemical examinations. The results indicate that entorhinal transplants survive to old age and that both the host and transplant tissues maintain morphological features consistent with those of short-term neural grafts. An unexpected finding of this experiment was the persistence in the transplanted tissue and adjacent host cortex of a pattern of AChE staining which is typical of early postnatal development.

Bronchoalveolar lavages in two patients with miliary tuberculosis have shown lymphocytic alveolitis. A 6-month regimen with an initial intensive 2-month phase resulted in remarkable clinical and radiographic improvement in both. However, bronchoalveolar lavage following treatment has shown that there was a persistence of lymphocytic alveolitis, though with reduced intensity. The significance of the persisting alveolitis, despite treatment, is not known at present. There is also a suggestion that compartment-alisation of lymphocytes may occur in miliary tuberculosis of the lung.

A controlled clinical trial of three short-course chemotherapy regimens was undertaken in patients with newly diagnosed bacteriologically positive pulmonary tuberculosis. The patients were randomly allocated to receive one of three regimens: rifampicin, streptomycin, isoniazid and pyrazinamide daily for 2 months, followed by streptomycin, isoniazid and pyrazinamide twice weekly for 3 months (R/5) or for 5 months (R/7), or the same regimen as R/7 but without rifampicin (Z/7). A bacteriological relapse requiring retreatment occurred by 5 years in 7.1% of 126 R/5, 4.0% of 124 R/7 and 6.7% of 253 Z/7 patients with organisms initially sensitive to streptomycin and isoniazid; none of these differences is statistically significant. Of the 31 relapses, 16 occurred within 2 years of the completion of chemotherapy and the remaining 15 between 2 and 5 years. Among 65 patients with initial drug resistance to streptomycin or isoniazid or both, there were six bacteriological relapses requiring retreatment.

Flow volume loops using computerised pulmonary function testing equipment were analysed in twenty sportsmen of Loyola College, Madras. There was no significant difference in mean P.E.F.R. (P greater than 0.2) and VE 25% (P greater than 0.2) in sportsmen, compared to Indian or American normals. On the other hand, the mean VE 50% (P less than 0.05) and VE 75% (P less than 0.001) were significantly higher in sportsmen compared to Indian values, but was similar to those reported in American normals (P greater than 0.1). Inspiratory flow rates were similar to those reported in Indians. Our results show that there is an increase in maximal expiratory flow rates at lower lung volumes in Southern Indian College Sportsmen compared to Indian normals.

Our previous morphologic studies in the rat demonstrated that exposure to lead during the preweaning period induced delays in the maturation of late-developing regions of the hippocampal formation at 15 days of age, followed by normal development or hypertrophy of the same areas in young adulthood. The present study was carried out to determine whether or not subtle or latent effects of such exposure to lead may be unmasked with the additional challenge of aging. To do this, mid-dorsal sections of the hippocampal formation from middle-aged (578-631 days old) Long-Evans control rats and from rats exposed to lead from birth until weaning via dams drinking 0.2% lead acetate were analyzed by light and electron microscopy. Exposure to lead did not alter areas of either neuropil or neuronal layers of the hippocampus or the dentate gyrus or the numbers per section or numerical densities (numbers per unit area) of neurons in hippocampal CA3 stratum pyramidale or dentate stratum granulosum. It did reduce mean size of complex invaginated mossy fiber synapses without altering their numbers in the proximal (close to dentate gyrus) mossy fiber zone, which was the zone also affected at 15 and 90 days of age in our previous studies.

Phorbol myristate acetate (PMA) triggered hydrogen peroxide (H2O2) release from alveolar macrophages and corresponding blood monocytes were studied as a whole, in active tuberculosis, inactive tuberculosis (treated), non-tuberculous lung disease patients and normal individuals. Irrespective of the study subjects, the alveolar macrophages produced less H2O2 than the corresponding blood monocytes. The alveolar macrophages that were resistant to OKIa1 (Anti-DR monoclonal antibody and complement treatment) produced an increased level of H2O2 than the control ascites and complement treated alveolar macrophages. Moreover, such increase in H2O2 release was not seen with peripheral blood monocytes; more than 90% monocytes were OKIa1 resistant population. These OKIa1 resistant alveolar macrophages are probably important in their metabolic, microbicidal and the immunological functions.

Morphogenesis, distribution of cholinergic enzyme acetylcholinesterase and synaptogenesis in the dentate gyrus of the rhesus monkey during the pre- and postnatal periods of development were examined using histological, histochemical and ultrastructural methods. The pattern of neuronal differentiation in the dentate gyrus demonstrated distinct superficial-to-deep and lateral-to-medial gradients. The histochemical reaction for acetylcholinesterase was present on gestation day 120 as minimal staining in the supragranular band and in the inner one-third of the dentate molecular layer. At term, the laminar distribution of the enzyme assumed mature pattern although considerable enhancement in staining intensity was achieved postnatally. At term and at 9 months of postnatal age, the most pronounced enzyme activity was found in the supragranular band and in the inner one-third of the molecular layer. Synaptogenesis in the dentate molecular layer was characterized by the early formation of axo-dendritic contacts on dendritic trunks and branches followed by the appearance of synapses on simple and complex spines. Spines were detected infrequently on gestation day 132. On day 148, they ranged in morphology from short stubby protrusions to pedunculated, triangular processes. The majority of the spines exhibited flat postsynaptic surfaces. Complex, synapse-bearing U- and W-shaped spines were observed rarely at this age but appeared more frequently at term and at 15 months of postnatal age. However, at all ages, including 15 months postnatally, synapses on flat-surfaced simple spines predominated. Most synapses were of the asymmetric variety. With certain exceptions, these features of development of the rhesus dentate gyrus resemble the reported patterns of postnatal ontogenesis of this structure in the rat. However, the ingrowth of cholinergic afferents and the major modifications in synapse structure occur prenatally in the rhesus monkey during the second half of the gestation period. This temporal difference between the two species should receive consideration in the planning of neuroplasticity experiments designed to explore lesion-induced adaptations in afferent growth and synaptogenesis in the rhesus dentate gyrus., (Copyright © 1983. Published by Elsevier Ltd.)

Neurotoxic sequelae of developmental lead exposure suggest that the hippocampus may be affected. Therefore, rats received low-level exposure via the milk of dams drinking 0.2% lead acetate beginning at parturition, and mid-dorsal sections of the hippocampus and dentate gyrus (DG) from 15-day-old pups were examined by light and electron microscopy. Lead exposure did not reduce body weight nor produce obviously abnormal vascularity or signs of cytotoxicity in the hippocampal formation, and total numbers per section of dentate granule cells or CA3 pyramidal cells were not reduced. On the other hand, lead exposure reduced neuropil development as evidenced both by reduced areas of the dentate hilus and dentate infrapyramidal stratum moleculare and by increased number of hilar CA3 pyramidal cells per unit area. Also, lead exposure reduced numbers of several types of synaptic profiles per unit area in the suprapyramidal mossy fiber zone. Complex invaginated (CI) profiles, assumed to be mature mossy fiber boutons, were characterized by multiple membrane densities and deep invaginations around dendritic spines of pyramidal cells. Complex noninvaginated (CN) boutons exhibited bag-like profiles with multiple membrane densities. Smaller, less numerous, simple (S) profiles contacted either dendritic trunks (ST) or spines (SS). Lead exposure reduced the numerical density of any of the profiles in the deep (close to stratum pyramidale) part of the proximal (close to DG) region of the suprapyramidal mossy fiber zone, but did not alter the numerical density of any of the profiles in the superficial (distal to stratum pyramidale) parts of either proximal or distal (close to CA1) regions. Average size of CN profiles in the distal region was increased by lead exposure. The pattern of effects suggests that low-level lead exposure during development preferentially affects later developing structures within the hippocampal formation, rather than affecting mature structures.

In the hippocampus of young and aged rats, lysosomal acid phosphatase and beta-glucuronidase were localized by enzyme histochemistry to the pyramidal and granule cells and to the mossy fiber zone (acid phosphatase only). Following a unilateral entorhinal lesion, enhancement in enzyme staining was observed within GFA (glial fibrillary acidic) protein-positive astrocytes and in cells resembling microglia and oligodendroglia in the ipsilateral dentate outer molecular layer and the hippocampal stratum lacunosum-moleculare. In young animals, these changes, first detected on day 2 post-lesion, were maximum on days 4 and 10 post-lesion and declined subsequently. The aged animals exhibited a delayed time-course of enzyme changes with minimal increases on days 2 and 4 post-lesion and greater increases on days 10 and 30 and gradual diminution thereafter. The delayed lysosomal response in the aged animal paralleled a reduction in the induction of glial cells following the lesion. Our findings suggest that the previously reported impairment in the clearing of degeneration debris in the aged animal is mediated by reduced glial induction and delayed glial lysosomal activation.

Young adult male rats received subcutaneous implants of Alzet osmotic minipumps which delivered 400 micrograms hydrocortisone per day. Untreated rats received no pumps or pumps containing the vehicle. Five days after receiving the implantation, both groups of rats were subjected to unilateral entorhinal lesion. Seven days after surgery, brains were analyzed quantitatively for glial changes in the denervated dentate outer molecular layer. Numerical densities of astrocytes and nonastrocytic glia were calculated by cell counting using 1.0-micron toluidine blue-stained sections. Glial acid phosphatase staining was quantitated using computer-assisted cytophotometric measurement of individual glial cells. Hydrocortisone-treated animals demonstrated 31% more astrocytes and 22.4% less nonastrocytes in the dentate outer molecular layer compared with untreated animals. Glia in the treated animals also showed a 33% decrease in average optical density of cytoplasmic acid phosphatase staining. These findings suggest that hydrocortisone treatment prior to and following an entorhinal lesion accelerates lesion-induced migration of astrocytes to the outer molecular layer, and reduces the increase in microglial number resulting from the lesion. The observed effect on microglia may result from a direct hormonal inhibition of local proliferation of microglia or from the well known systemic anti-inflammatory action of glucocorticoids on monocytes, the putative precursors of brain microglia. Our findings suggest that glucocorticoid hormones significantly alter the response of non-neuronal cells to neural tissue damage.

The activity and distribution of the cholinergic neurotransmitter enzymes acetylcholinesterase (AChE) and choline acetyltransferase (ChAc) in the developing cerebellum of the mouse were investigated using biochemical assays and light microscopic histochemistry for AChE and ChAc, and electron microscopic histochemistry for AChE. Postnatal alterations in the levels of AChE and ChAc in the cerebellum of the mouse are characterized by a divergent pattern. During the first two postnatal weeks, AChE activity increases progressively, whereas ChAc activity remains low. Beyond day 14, when AChE activity is steady or gradually decreasing, ChAc increases sharply to reach a peak on day 32. Histochemically, AChE activity is associated with the glomeruli and the Golgi cells of the internal granular layer, the medullary layer, and the deep cerebellar nuclei. Purkinje cells exhibit transient staining between days 2 and 9. At the structural level, AChE staining is first demonstrated on day 6 within the Golgi cell soma, on day 9 at the mossy fiber-granule cell synapse, and on day 11 at the Golgi terminal-granule cell synapse. The staining intensity of these structures reaches that of the adult on day 19. The histochemical reaction for ChAc is localized to moderate number of presumed Bergmann glial cells, a few large cells of the deep cerebellar nuclei, small numbers of Golgi cells, and all immature Purkinje cells. The molecular distribution of ChAc sharply contrasts with the localization established by other methods previously and is interpreted in the light of the drawbacks of the histochemical procedure. The biochemical fluctuations in AChE activity, correlated with the histochemical and cytochemical data, suggest that the postnatal increases in the enzyme are related to the ingrowth of the mossy fibers and to the maturation of the AChE-positive Golgi cells. Histochemical evidence for the correlation between the ontogenetic increases in cerebellar ChAc activity and progressive mossy fiber innervation must await the application of the immunohistochemical method to the developing cerebellum.

Immunohistochemical staining for glial fibrillary acidic protein (GFAP) was employed as a tool for quantification of astrocytes in the rat brain. One-micron-methacrylate sections were prepared from 70-micron slices stained for GFAP by using a preembedding staining procedure. Numbers/unit area of astrocytes and nonastrocytes were determined for cortex, corpus callosum, and hippocampal neuropil. In each, counts from GFAP-stained, toluidine-blue-counterstained sections were compared with counts obtained from sections stained with toluidine blue alone. Numbers of nonastrocytes and total glia in all three regions were comparable in both groups of sections. Astrocyte counts in the cortex and hippocampus also showed no significant differences between the two groups. In contrast, the number of astrocytes in the corpus callosum was significantly lower in GFAP-stained, toluidine-blue-counterstained sections than in sections stained with toluidine blue alone. GFAP immunohistochemistry is a useful tool for the quantification of astrocytes in semi-thin plastic sections of rat brain.

The activity and distribution of the enzyme acetylcholinesterase in the cerebellum of adult lurcher (Lc) mutant mice and of their normal littermates was investigated using biochemical assay and light microscopic histochemistry. The biochemical assay demonstrated an approximate two-fold increase of enzyme activity in the lurcher cerebellum compared to the values obtained for the normal controls. Acetylcholinesterase activity in the cerebellum of the normal adult mouse was predominantly evident in the granular layer, corresponding to the location of the glomeruli. In contrast, the lurcher cerebellum exhibited enzyme activity in both molecular and granular layers. In the molecular layer the staining appeared to be associated with ectopic granule cells. In both normal and lurcher mice, the Golgi cells, subcortical white matter and deep nuclei also showed varying degrees of staining for acetylcholinesterase.

We previously observed that lead exposure beginning at parturition reduced or retarded neuropil development and synaptogenesis in specific regions of the hippocampal formation in 15-day-old rats. To determine if morphologic effects of perinatal lead exposure persist into adulthood, the hippocampus of rats exposed to lead from parturition to weaning via the milk of dams drinking 0.2% lead acetate was analyzed by light and electron microscopy at 90-97 days of age. Preweaning lead exposure did not cause obvious hippocampal cytotoxicity, edema, damaged vasculature or altered numerical density (number per unit area) of dentate granule or hippocampal pyramidal neurons. However, lead exposure increased the area of the hilar portion of stratum pyramidale, increased the number of blood vessels per section in the dentate stratum granulosum and tended to increase the number of glial cells per section in the non-hilar CA3 stratum pyramidale. Effects of early postnatal lead exposure on synaptic profiles in the suprapyramidal mossy fiber zone (MFZ) were limited to the proximal (close to the dentate gyrus) region of the extrahilar zone. Both numerical density and areal density (proportion of neuropil covered) of complex invaginated (Ci) profiles, typical of mature mossy fiber boutons, were increased by lead exposure in the deep (close to stratum pyramidale) subfield of the proximal portion of the suprapyramidal MFZ. Lead exposure tended to increase the mean cross-sectional area of Cl profiles in the superficial (distant from stratum pyramidale) subfield of the proximal portion, and reduced the cross-sectional area of complex noninvaginated (CN) synaptic profiles in some subfields. Although lead exposure reduced or delayed neuropil development in selected late developing hippocampal regions examined at 15 days of age, it appeared to allow normal growth or to induce compensatory hypertrophy in these same regions in the adult.

Bronchoalveolar lavage using flexible fibreoptic bronchoscope was carried out in 50 patients 1-2 1/2 yr after exposure to the 'toxic gas' at Bhopal. Thirty six patients in the analysis were categorised into 3 groups (viz., mild, moderate and severe), depending upon the severity of exposure. There was an increase in cellularity in the lower respiratory tract (alveolitis) of the severely exposed patients (in both smokers and non-smokers), compared to normals (P less than 0.05). The increase in cellularity in severely exposed non-smokers was due to abnormal accumulation of macrophages (P less than 0.01), and in severely exposed smokers, to macrophages (P less than 0.01) and neutrophils (P less than 0.05). Mild and moderately exposed patients did not show significant change in cellularity in lower respiratory tract, compared to normal individuals (P greater than 0.2). There was a trend towards increasing cellularity, as the severity increased (P less than 0.0001) and higher numbers of total cells were seen in severely exposed smokers, suggesting that smoking is a risk factor. It appears, therefore, that subjects severely exposed to the toxic gas at Bhopal may have a subclinical alveolitis characterised by accumulation and possibly activation of macrophages in the lower respiratory tract. Smokers, who were exposed to the gas had in addition, accumulation of neutrophils.

The time-course and magnitude of astrocyte proliferation following neural trauma was evaluated in young adult (3 months) and mid-aged (16-19 months) male Fischer 344 rats. One to 4 days after a needle wound was made through the cortex and the hippocampus, rats received three intraperitoneal injections of 3H-thymidine at 8 hour intervals and were sacrificed 1 hour after the last injection. For astrocyte quantification, 3H-thymidine autoradiography was combined with immunohistochemical staining for glial fibrillary acidic protein followed by semithin sectioning. In areas of the cortex and hippocampus adjacent to the wound, astrocytes were categorized as unlabeled or labeled with silver grains over the nuclei. Labeling index and numerical density of astrocytes were determined using stereological methods. The results showed that in both young and older rats, astrocyte proliferation is an early glial response to neural trauma, occurring during the first 4 postlesion days and contributing to an increase in astrocyte population. Regional differences in labeling index and numerical density suggest heterogeneity in the proliferative capacity of astrocyte subpopulations in the rat brain. Compared with young animals, older rats demonstrated greater labeling in the cortex but not in the hippocampus. Thus, aging is associated with region-specific increase in astrocyte reactivity to trauma possibly due to increased availability of mitogens or enhanced sensitivity of astrocytes to mitogenic signals.

Swiss-Webster outbred mice were fed marginally or severely zinc deficient diets (9 or 2 ppm zinc) from day 16 gestation to day 15 postnatal. Control mice were fed a 100 ppm diet either ad lib or in amounts equal to the diet intake of deprived mice (pair fed controls). Male and female offspring were tested at 70 days of age in a one-trial passive avoidance task with a 30 min train-test interval. Both marginally and severely zinc deprived offspring (but not pair fed controls) had shorter avoidance latencies than offspring of ad lib fed zinc replete controls. Zinc deprived offspring did not differ from control mice when either baseline or "stressed" (exposure to novel environment) plasma corticosterone levels were quantitated. Further, zinc staining patterns of the hippocampus (Timm-sulfide stain) were not altered in the nutritionally deprived offspring. Thus marginal dietary zinc deficiency during development can lead to impaired passive avoidance performance in adult mice. This behavioral effect is not associated with altered pituitary-adrenocortical activity or with a permanent reduction in hippocampal zinc staining. This result has significant implications for the influence of zinc deprivation in utero and in the neonatal animal on adult behavior characteristics.

Morphogenesis of the hippocampal mossy fiber synapses (MFSs) in fetal and postnatal rhesus monkeys was examined by electron microscopy. Typical invaginated MFSs were absent on gestation days 90 and 109 and were detected infrequently on day 132. In older fetuses and postnatal animals of 16 days and 9 months of age, the percentage of invaginated MFSs increased and the synapses exhibited increases in the number of invaginated spines and density of synaptic vesicles and greater maturity of the spines. At all ages, MFSs exhibited a wide range of maturity which may be correlated with the reported protracted generation of dentate granule cells in the rhesus monkey. The pattern of morphogenesis of MFSs in the monkey suggests that as in the rat, it is very likely that the mossy fibers contact pyramidal cells prior to the emergence of the 'thorny excrescences' and that this is followed by progressive maturation of the MFSs. The time-course of major morphogenetic modifications in MFSs in the rhesus monkey corresponds to the period of elaboration of complex spines and synapses in the dentate molecular layer. On this basis, it is suggested that these two processes are interrelated developmental events.