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1.
Indian J Crit Care Med ; 23(2): 78-82, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31086451

RESUMO

BACKGROUND: Critically ill obstetric patients represent a small proportion of intensive care unit (ICU) admissions. Physiological changes of pregnancy along with pregnancy specific diseases may lead to rapid deterioration of the health status of the parturient warranting ICU care. The present study aims to study the clinical profile and outcomes of the obstetric patients requiring ICU care. STUDY DESIGN AND SETTINGS: Prospective observational study in the multidisciplinary ICU of a tertiary care teaching hospital conducted for a period of 2 years. MATERIALS AND METHODS: Demographic details, indication for ICU admission, severity of illness scores, interventions, complications and outcomes of the consecutive obstetric patients transferred to ICU were studied. RESULTS: Ninety-one patients were admitted (26 per 1000 deliveries) to the ICU. Majority of them were postpartum (84.6%) and unbooked or referred (63.8%). Hypertensive disorders (24.2%) and obstetric hemorrhage (23.1%) were the major cause for admission to ICU. Forty three patients (47.3%) underwent cesarean delivery. Mechanical ventilation (54.9%), blood transfusion (46%), vasopressor therapy (22%) and dialysis (9.9%) were the various interventions provided in the ICU. Patients with sepsis had high mortality accounting for one third of ICU mortality. The ICU mortality rate was 9.9%. CONCLUSION: The present study showed a clinical profile and outcomes similar to the current scenario of critically ill obstetric patients nationwide. Further studies with a larger sample size may provide a better insight in this population. HOW TO CITE THIS ARTICLE: Sailaja B, Renuka MK, et al. Critically Ill Obstetric Admissions to an Intensive Care Unit: A Prospective Analysis from a Tertiary Care University Hospital in South India. Indian J of Crit Care Med 2019;23(2):78-82.

2.
Asian Pac J Cancer Prev ; 14(4): 2221-4, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23725116

RESUMO

The glutathione S-transferases (GSTs) are a family of enzymes involved in the detoxification of a wide range of chemicals, including important environmental carcinogens, as well as chemotherapeutic agents. In the present study 294 acute leukemia cases, comprising 152 of acute lymphocytic leukemia (ALL) and 142 of acute myeloid leukemia, and 251 control samples were analyzed for GSTM1 and GSTT1 polymorphisms through multiplex PCR methods. Significantly increased frequencies of GSTM1 null genotype (M0), GSTT1 null genotype (T0) and GST double null genotype (T0M0) were observed in the both ALL and AML cases as compared to controls. When data were analyzed with respect to clinical variables, increased mean levels of WBC, Blast %, LDH and significant reduction in DFS were observed in both ALL and AML cases with T0 genotype. In conclusion, absence of both GST M and GST T might confer increased risk of developing ALL or AML. The absence of GST enzyme might lead to oxidative stress and subsequent DNA damage resulting in genomic instability, a hallmark of acute leukemia. The GST enzyme deficiency might also exert impact on clinical prognosis leading to poorer DFS. Hence GST genotyping can be made mandatory in management of acute leukemia so that more aggressive therapy such as allogenic stem cell transplantation may be planned in the case of patients with a null genotype.


Assuntos
Glutationa Transferase/genética , Leucemia Mieloide Aguda/etiologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/etiologia , Deleção de Sequência , Adolescente , Adulto , Estudos de Casos e Controles , Criança , DNA/análise , DNA/genética , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Leucemia Mieloide Aguda/patologia , Masculino , Reação em Cadeia da Polimerase , Polimorfismo Genético/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Prognóstico , Fatores de Risco , Adulto Jovem
3.
EXCLI J ; 12: 373-83, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-26417233

RESUMO

The objective of the present study was to evaluate the possible protective effects of Tribulus terrestris fruit aqueous extract (TTFAEt) on lipid profile and oxidative stress in isoproterenol (ISO) induced myocardial necrosis in albino Wistar rats. Albino Wistar rats were divided into normal control, TTFAEt alone treated, ISO control and pretreated (TTFAEt+ISO) groups. The extract was administered at a dose of 50 mg/kg body weight for 40 days orally by gavage and ISO was administered at a dose of 85 mg/kg body weight for two consecutive days intraperitoneally at an interval of 24 h. ISO induced myocardial infarction (MI) was confirmed by disturbances in serum lipid profile, heart tissue lipid peroxidation and antioxidant enzyme levels. There was a significant increase in the levels of serum total cholesterol (32.60 %), triglycerides (41.30 %), very low density lipoproteins (81.81 %), low density lipoproteins (84%) and phospholipids (38.88 %) and a significant decrease in the levels of high density lipoproteins (33.33 %) in the ISO control group when compared to normal controls. Additionally, there is a significant decrease in the levels of heart tissue antioxidant enzymes such as superoxide dismutase, catalase, glutathione reductase, glutathione peroxidase and depletion of reduced glutathione, which indicates enhanced lipid peroxidation(172 %). Pretreatment with extract significantly showed a protective effect against ISO altered lipid profile, lipid peroxidation and antioxidant enzyme levels. The present study showed therapeutic effect of TTFAEt on lipid profile and oxidative stress in isoproterenol (ISO) induced myocardial necrosis in experimental rats.

4.
J Nat Sci Biol Med ; 3(2): 182-5, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23225982

RESUMO

BACKGROUND: TP53, located on chromosome 17p13, is one of the most mutated genes affecting many types of human cancers. Thus, we aimed at investigating the association of SNPs in TP53 gene with chronic myeloid leukemia (CML). MATERIALS AND METHODS: A total of 236 CML and 157 control samples were analysed for mutations in TP53 gene using polymerase chain reaction followed by direct sequencing. RESULTS: Sequencing analysis for mutations in exons 7-9 of the TP53 gene revealed four SNPs, three in intron 7 (C14181T, T14201G, and C14310T) and one SNP in intron 6 (A13463G) of TP53 gene. The mutation C14181T is located at position 72 base pairs downstream of the 3'-end of exon 7 of the P53 gene. This mutation is in complete linkage disequilibrium with a T14201G mutation, 20 base pairs further downstream occurring at position 14201. This mutation occurred only in the presence of C14181T mutation and these mutations showed association with advanced phase and cytogenetic poor response. Another two novel mutations, C14310T in intron 7 and A13463G in intron 6 were also found to be associated with cytogenetic poor response. CONCLUSION: Our study suggests that TP53 intronic SNPs might have a strong influence on disease progression and poor response in CML patients.

5.
Asian Pac J Cancer Prev ; 13(1): 347-50, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22502699

RESUMO

TP53 is the mostly commonly mutated gene in many cancers and the P53 tumor suppressor protein is involved in multiple cellular processes, including transcription, DNA repair, genomic stability, senescence, cell cycle control and apoptosis. A common single nucleotide polymorphism located within the proline rich region of TP53 gene at codon 72 in exon 4 encodes either proline or arginine. TP53 Arg 72 is more active than TP53 Pro 72 in inducing apoptosis. The aim of this study was to understand the association of the 72 codon polymorphism with acute leukemia development and prognosis. A total of 288 acute leukemia cases comprising 147 acute lymphocytic leukemia (ALL) and 141 acute myeloid leukemia (AML), as well as 245 controls were recruited for analysis of the TP53 72 polymorphism using PCR-RFLP method. Significant association of homozygous arginine genotype with AML was observed (χ2- 133.53; df-2, p < 0.001. When data were analyzed with respect to clinical variables, elevation in mean WBC, blast %, LDH levels and slight reduction in DFS in ALL cases with the arginine genotype was observed. In contrast, AML patients with Pro/Pro had elevated WBC, Blast%, LDH levels with slightly reduced DFS. Our study indicates that Arg/Arg genotype might confer increased risk to development of acute myeloid leukemia.


Assuntos
Códon/genética , Leucemia Mieloide Aguda/genética , Polimorfismo Genético/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Proteína Supressora de Tumor p53/genética , Adolescente , Adulto , Estudos de Casos e Controles , Criança , DNA/genética , Feminino , Humanos , Masculino , Reação em Cadeia da Polimerase , Prognóstico , Fatores de Risco
6.
Plant Cell Rep ; 30(3): 425-36, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21212957

RESUMO

A reproducible and efficient transformation method was developed for the banana cv. Rasthali (AAB) via Agrobacterium-mediated genetic transformation of suckers. Three-month-old banana suckers were used as explant and three Agrobacterium tumefaciens strains (EHA105, EHA101, and LBA4404) harboring the binary vector pCAMBIA1301 were used in the co-cultivation. The banana suckers were sonicated and vacuum infiltered with each of the three A. tumefaciens strains and co-cultivated in the medium containing different concentrations of acetosyringone for 3 days. The transformed shoots were selected in 30 mg/l hygromycin-containing selection medium and rooted in rooting medium containing 1 mg/l IBA and 30 mg/l hygromycin. The presence and integration of the hpt II and gus genes into the banana genome were confirmed by GUS histochemical assay, polymerase chain reaction, and southern hybridization. Among the different combinations tested, high transformation efficiency (39.4 ± 0.5% GUS positive shoots) was obtained when suckers were sonicated and vacuum infiltered for 6 min with A. tumefaciens EHA105 in presence of 50 µM acetosyringone followed by co-cultivation in 50 µM acetosyringone-containing medium for 3 days. These results suggest that an efficient Agrobacterium-mediated transformation protocol for stable integration of foreign genes into banana has been developed and that this transformation system could be useful for future studies on transferring economically important genes into banana.


Assuntos
Agrobacterium tumefaciens/genética , Técnicas de Transferência de Genes , Musa/genética , Sonicação , Acetofenonas/química , Cinamatos/farmacologia , DNA de Plantas/genética , Genes Reporter , Vetores Genéticos , Higromicina B/análogos & derivados , Higromicina B/farmacologia , Plantas Geneticamente Modificadas/genética , Técnicas de Cultura de Tecidos , Transformação Genética , Vácuo
7.
Indian J Hum Genet ; 17(3): 175-8, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22345989

RESUMO

BACKGROUND: CYP3A5 was observed to be an important genetic contributor to inter individual differences in CYP3A-dependent drug metabolism in acute leukemic patients. Loss of CYP3A5 expression was mainly conferred by a single nucleotide polymorphism at 6986A>G (CYP3A5*3). We investigated the association between CYP3A5*3 polymorphism and acute leukemia. MATERIALS AND METHODS: Two hundred and eighty nine acute leukemia cases comprising of 145 acute lymphocytic leukemia (ALL), 144 acute myeloid leukemia and 241 control samples were analyzed for CYP3A5*3 polymorphism using PCR-RFLP method. Statistical analysis was performed with SPSS version (15.0) to detect the association between CYP3A5*3 polymorphism and acute leukemia. RESULTS: The CYP3A5*3 polymorphism 3/3 genotype was significantly associated with acute leukemia development (χ(2)- 133.53; df-2, P 0.000). When the data was analyzed with respect to clinical variables, mean WBC, blast % and LDH levels were increased in both ALL and AML cases with 3/3 genotype. The epidemiological variables did not contribute to the genotype risk to develop either AML or ALL. CONCLUSION: The results suggest that the CYP3A5*3 polymorphism might confer the risk to develop ALL or AML emphasizing the significance of effective phase I detoxification in carcinogenesis. Association of the polymorphism with clinical variables indicate that the 3/3 genotype might also contribute to poorer survival of the patients.

8.
Asian Pac J Cancer Prev ; 12(8): 1893-8, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22292621

RESUMO

The p53 protein is at the center of cell regulatory pathways influencing transcription and activity of several replication and transcription factors. In exon 4 of the gene TP53, a codon 72 polymorphism causing an Arg/Pro substitution has been reported in breast and other cancers. This substitution is in the putative SH3 binding domain of p53 protein, influencing binding capacity and thereby functional properties. In the present investigation of a relatively large series of cases in India, the frequency of the homozygous arginine genotype (33.2%) was significantly higher in the breast cancer group as compared to controls (19.6%), χ2 =11.791 (P=0.003). Patients with premenopausal breast cancer had a more elevated frequency (41.1%) than postmenopausal cases (25.4%) although the genotype frequency distribution did not show significant variation with respect to hormonal receptor status. Elevation was greatest in patients in advanced stages of cancer. The hetrozygote frequency (Arg/Pro) was also found to be increased in overweight and obese women with breast cancer. TP53 codon 72 polymorphism might predispose individual for the development of breast cancer as well as to bad prognosis. Intronic variants may affect gene regulation through aberrant splicing or through disruption of critical DNA-protein interaction. While no significant association was observed with relation to CC genotype as well as C allele of G13964C intron polymorphism with breast cancer, the C allele frequency showed association with respect to other risk confounding factors which might play role in progression of breast cancer.


Assuntos
Neoplasias da Mama/genética , Códon , Íntrons , Proteína Supressora de Tumor p53/genética , Alelos , Arginina/genética , Estudos de Casos e Controles , Progressão da Doença , Feminino , Frequência do Gene , Predisposição Genética para Doença , Heterozigoto , Homozigoto , Humanos , Índia , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Obesidade/genética , Polimorfismo Genético
9.
Asian Pac J Cancer Prev ; 11(4): 1063-6, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21133625

RESUMO

The multidrug resistance (MDR1) gene product P-glycoprotein is a membrane bound protein that functions as an ATP-dependent efflux pump, transporting exogenous and endogenous substrates from the cells. Since it plays an important role in chemotherapy, there is an increasing interest in the possible significance of genetic variation in MDR1. Our main objective was to study the MDR1gene polymorphism at C3435T with reference to development and progression of acute leukemia. The present study included 290 acute leukemia cases, comprising of 147 acute lymphocytic leukemia (ALL), 143 acute myeloid leukemia and 249 age-sex matched control samples for the analysis of MDR1 C3435T polymorphism, by the PCR-RFLP method. The MDR1 genotype distribution revealed an elevated frequency of the TT genotype in ALL cases (51.7%) as compared to controls (28.9%), whereas AML group did not show any association. The mean white blood cell count, blast% and LDH levels were increased in ALL patients with the CC genotype. No deviation was observed with respect to hematoglobin, platelet count and disease free survival in ALL patients. The association of CC genotype with clinical variables in ALL indicated that the CC genotype with high expression might be eliminating antileukemic drugs (anthracyclines, Daunorubicin, Vincristeine, Mitoxanthrone) which are P-gp substrates, leading to lower intra cellular drug concentrations and a poor prognosis. Such an association with the CC genotype was not observed in AML. In conclusion, these results suggested that the MDR1 TT genotype might influence risk of development of acute lympoblastic leukemia and the CC genotype might be linked to a poor prognosis of ALL.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Genes MDR/genética , Leucemia Mieloide Aguda/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Subfamília B de Transportador de Cassetes de Ligação de ATP , Adolescente , Adulto , Estudos de Casos e Controles , Distribuição de Qui-Quadrado , Criança , Feminino , Frequência do Gene , Genótipo , Humanos , Índia/epidemiologia , Leucemia Mieloide Aguda/tratamento farmacológico , Masculino , Polimorfismo de Nucleotídeo Único , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Prognóstico , Resultado do Tratamento , Adulto Jovem
10.
Asian Pac J Cancer Prev ; 11(3): 781-4, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21039054

RESUMO

CYP3A5 is a member of the CYP3A gene family which metabolizes 50% of therapeutic drugs and steroid hormones. CYP3A5*3 and CYP3A5*6 polymorphisms exhibit inter-individual differences in CYP3A5 expression. The CYP3A5*3 allele (A6986G transition in intron 3) results in loss of CYP3A5 expression and the CYP3A5*6 allele (G14690A transition in exon 2, leading to the skipping of exon 7) is associated with lower CYP3A5 catalytic activity. The aim of the present study was to investigate their influence on susceptibility to chronic myeloid leukemia (CML). 265 CML cases and 241 age and sex matched healthy controls were analyzed by the PCR-RFLP technique. The frequencies of homozygous 3/3 genotype and CYP3A5*3 allele were elevated significantly in the CML group compared to controls (χ²=93.15, df=2, p=0.0001). With respect to clinical parameters, CYP3A5*3 allele frequency was increased in patients with advanced phase of the disease (0.71) as compared to those in chronic phase (0.65). Patients without hematological response (minor/poor) had higher frequency of 3/3 genotype (54.54%) as compared to those with major hematological response (41.2%). CYP3A5*6 allele was not observed in cases as well as in controls. Our study suggests that the CYP3A5*3 gene polymorphism is significantly associated with the risk of CML development and disease progression.


Assuntos
Citocromo P-450 CYP3A/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Polimorfismo Genético/genética , Adolescente , Adulto , Idoso , Estudos de Casos e Controles , Criança , Feminino , Frequência do Gene , Genótipo , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Prognóstico , Fatores de Risco , Taxa de Sobrevida , Adulto Jovem
11.
Asian Pac J Cancer Prev ; 11(6): 1653-7, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21338212

RESUMO

The human CYP17 gene, located on chromosome 10q24.3, plays a key role in sex steroid synthesis, mainly related to estrogen. A 5' UTR polymorphism involving a single base pair change in the promoter region results in increased transcriptional activity. In the present study of 250 breast cancer cases and 250 ma tched controls, the A1 genotype frequency was elevated in the disease group, while the A2 genotype frequency demonstrated no association. When data were stratified by risk conferring group, however, the A2 genotype frequency was increased in postmenopausal breast cancer cases (4.2%), patients positive for a family history of breast cancer (5.5%), high BMI, estrogen receptor (6.2%) and progesterone receptor negative (5.0%) status, HER2/neu positive (7.7%) status, positive node status (5.0%) as well as advanced stage of the disease. The A1A1 genotype linked with increased production of androgens might impact on onset of breast cancer while the A2 allele showed associations with respect to important risk conferring parameters.


Assuntos
Neoplasias da Mama/genética , Mama/patologia , Polimorfismo Genético/genética , Esteroide 17-alfa-Hidroxilase/genética , Estudos de Casos e Controles , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Índia , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Prognóstico , Fatores de Risco
13.
Indian J Med Sci ; 63(1): 13-20, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19346634

RESUMO

BACKGROUND: The Cytochrome P-4501A1 (CYP1A1) gene, located on chromosome 15q, is involved in the metabolism of carcinogens mainly polycyclic aromatic hydrocarbons as well as estrogen. It is considered as candidate gene for low-penetrance breast cancer susceptibility. Hence the present study aims to discuss the role of CYP1A1 polymorphisms in breast cancer. MATERIALS AND METHODS: A total of 250 breast cancer patients and the same number of healthy age-matched controls were analyzed for the polymorphism of CYP1A1*2 by polymerase chain reaction-restriction fragment length polymorphism. RESULTS: In the present study, association of CYP1A1*2 (Ile 462Val) polymorphism with breast cancer was studied. Only one breast cancer patient was observed to be homozygous for Val allele but none among controls. The frequency of heterozygous Ile/Val genotype was found to be increased significantly in breast cancer patients (68.1%) as compared to controls (51.0%). Higher frequency of heterozygotes for Val allele was observed among premenopausal breast cancer patients and patients with high BMI, positive for HER2/neu status and advanced stage of the disease in comparison to the corresponding groups. No significant association of CYP1A1*2 polymorphism was observed with occupation, estrogen receptor and progesterone receptor status of breast cancer patients. CONCLUSIONS: In conclusion, our results suggest a significant correlation between CYP1A1*2 expression and the occurrence of breast cancer.


Assuntos
Neoplasias da Mama/genética , Citocromo P-450 CYP1A2/genética , Predisposição Genética para Doença , Polimorfismo Genético , Estudos de Casos e Controles , Feminino , Genótipo , Humanos , Receptores de Estrogênio/genética , Receptores de Progesterona/genética , Medição de Risco
14.
Indian J Hum Genet ; 13(3): 97-101, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21957356

RESUMO

BACKGROUND: Estrogen receptor (ER) is a ligand-inducible transcription factor that mediates estrogen action in target tissue. Several common polymorphisms of the ERα gene have been reported to be associated with alterations in receptor expression in breast cancer. MATERIALS AND METHODS: A case-control study was designed to compare 250 breast cancer patients with 250 age-matched healthy controls. The frequency distribution of PvuII polymorphism in the ERα gene was assessed by PCR-RFLP method. RESULTS: The frequency of the PP genotype (35.3%) was increased significantly in breast cancer patients when compared to controls (19.8%), with a corresponding increase in P allele frequency (χ(2)= 16.4; P = 0.0003). The OR for genotypes PP vs. Pp was 1.989 (95% CI: 1.2708 to 3.113). Premenopausal women with breast cancer had an elevated frequency of the PP genotype (22.8%) as compared to postmenopausal women (16.8%). The frequency of the PP genotype was increased in patients positive for ER and HER-2/neu as compared to those with receptor-negative status. The pp and p allele frequencies were increased in progesterone-receptor-negative status. When stage of the disease was considered, both Pp and pp genotype frequencies were elevated in patients with advanced stage breast cancer. The frequency of the P allele and PP genotype frequencies tended to increase with increase in body mass index, whereas the Pp genotype frequency was elevated only in obese patients. The reverse was observed in the case of pp genotype frequency. CONCLUSION: The study thus highlighted the influence of ERα PvuII polymorphism on the development and progression of breast cancer.

15.
J Environ Sci Eng ; 48(3): 189-90, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17915782

RESUMO

Glyphosate application resulted in a decline in soil pH with consequent increase in soil mycoflora suggesting an indirect relationship. Though the composition of mycoflora unchanged, species of aspergilli, fusaria, penicillia and Trichoderma were predominant. HPLC, IR analysis revealed the presence of sarcosine derivative as an intermediary of glyphosate degradation in soil.


Assuntos
Fungos/efeitos dos fármacos , Glicina/análogos & derivados , Herbicidas/farmacologia , Poluentes do Solo/farmacologia , Biodegradação Ambiental , Contagem de Colônia Microbiana , Fungos/fisiologia , Glicina/metabolismo , Glicina/farmacologia , Herbicidas/metabolismo , Concentração de Íons de Hidrogênio , Sarcosina/metabolismo , Microbiologia do Solo , Poluentes do Solo/metabolismo , Glifosato
16.
J Neural Transplant Plast ; 6(2): 73-81, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9306239

RESUMO

Fetal ventral mesencephalon from the 15th gestational day was grafted into the striatum of neonatal and adult rats. In one group of adult rats, fetal nigra was transplanted into normal striatum. In a second group, the tissue was transplanted at sites where dopaminergic fibers were denervated with 6-hydroxydopamine. The behavior of the dopaminergic neurons and glial reactions were studied by staining with cresyl violet to localize the transplants and by immunolabeling tyrosine hydroxylase (TH) and glial fibrillary acidic protein. In normal adults, the transplants were small. At the edge of the transplants, TH-positive neurons were packed into clusters, and an interface without any significant crossover of TH-positive fibers was present. Glial reaction was minimal in and around the transplant. In the denervated striatum, transplants were generally larger than those in normal striatum and surrounded by a glial scar. TH-positive neurons were both closely packed and loosely arranged at the periphery of the transplants. Processes could be clearly defined and could be traced to the adjacent host striatum through the TH-free denervated area. In neonates, the transplants were large and at times extended beyond the striatum. Most TH-positive neurons were arranged linearly along the periphery of the transplant. Cell bodies were widely separated and a well-developed neuropil was present. Fibers from the transplant mingled freely with the host striatum without any interface. In all three transplant groups, tracing the TH-positive neurites was easy because they were thicker and coarser than other elements. No apparent glial reaction occurred in the neonates. Thus, the growth and maturation of dopaminergic neurons seemed to vary in different environments. The most conducive environment appears to be neonatal brain in which growth factors are readily available.


Assuntos
Animais Recém-Nascidos/fisiologia , Transplante de Tecido Encefálico/fisiologia , Transplante de Células/fisiologia , Dopamina/fisiologia , Transplante de Tecido Fetal/fisiologia , Neostriado/fisiologia , Neurônios/transplante , Animais , Denervação , Neostriado/citologia , Neostriado/transplante , Neuroglia/efeitos dos fármacos , Neuroglia/fisiologia , Neurônios/fisiologia , Oxidopamina , Ratos , Ratos Wistar , Substância Negra/citologia , Simpatectomia Química , Transplantes , Tirosina 3-Mono-Oxigenase/metabolismo
18.
Int J Dev Neurosci ; 14(6): 761-70, 1996 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8960983

RESUMO

Electron microscopy of the maturing neurons and developing and maturing synapses in the substantia nigra of 14 human embryos/foetuses of 8-24 weeks of gestation are reported. At 8 weeks, cells were immature with very little cytoplasm and cellular organelles. Contact sites of processes appeared more electron dense than the other areas. At 12 weeks, many of the cells had acquired more cytoplasm and cellular organelles and could be identified as neurons. Asymmetric synapses with clear, round synaptic vesicles also were identifiable at this age. Such synapses, first to appear in the developing substantia nigra, are reported to be formed by recurrent collateral nigro-striatal fibres. Substance P fibres from the striatum also are contributing to this type of synapse. At 15-16 weeks, not only was the number of such synapses increased, but many appeared morphologically mature. Symmetric synapses having clear round vesicles along with a few dense core vesicles also appeared at this stage, suggesting striatal input. By 24 weeks of gestation, most of the neurons had cytological features comparable to that of the mature neurons. There was an increase in the total number of synapses and the individual variety from 15 to 24 weeks of gestation. The present study indicates that synaptogenesis starts at 8 weeks and continues beyond 24 weeks of gestation.


Assuntos
Feto/embriologia , Neurônios/ultraestrutura , Substância Negra/embriologia , Citoplasma/ultraestrutura , Retículo Endoplasmático Liso/metabolismo , Retículo Endoplasmático Liso/ultraestrutura , Idade Gestacional , Humanos , Neostriado/citologia , Neostriado/embriologia , Vias Neurais , Neurônios/metabolismo , Ribossomos/metabolismo , Ribossomos/ultraestrutura , Substância Negra/citologia , Sinapses/ultraestrutura
19.
Int J Dev Neurosci ; 14(4): 453-60, 1996 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8884378

RESUMO

The substantia nigra of gestation day 14 was transplanted into the striatum of 3-4-month-old rats to investigate the transplants ultrastructurally at the end of 2 years, as a follow-up to our previous studies. Transplants were of small size in all 10 specimens taken for this study. The changes observed in the transplant and in the interface region with the host striatum were: thickening of the blood vessel walls, perivascular cuffing with lymphocytes and macrophages loaded with tissue debris, degenerating neurons and hypertrophied astroglia containing dense granules indicating ageing or reaction to degeneration and glial processes. The number of surviving neurons in the transplants was small. These were smaller in size and had very few intracytoplasmic membraneous organelles. A higher content of intracytoplasmic ageing lipofuscin pigment was present than in host neurons and age-matched nigral neurons. Synapses were few, and their number varied among transplants. Generally, the synapses were at the interface with the host tissue. The changes observed in all the 2-year-old transplants suggest premature ageing or a slow rejection process. Slow rejection is a possibility, because these rats are only stock-bred, not inbred, and hence they are not completely immunologically compatible.


Assuntos
Neostriado/cirurgia , Substância Negra/transplante , Animais , Astrócitos/patologia , Contagem de Células , Senescência Celular/fisiologia , Artérias Cerebrais/patologia , Rejeição de Enxerto/fisiopatologia , Lipofuscina/análise , Lisossomos/química , Lisossomos/ultraestrutura , Macrófagos/fisiologia , Macrófagos/ultraestrutura , Microscopia Eletrônica , Neostriado/irrigação sanguínea , Neostriado/ultraestrutura , Degeneração Neural/fisiologia , Neurônios/citologia , Neurônios/transplante , Neurônios/ultraestrutura , Organelas/química , Ratos , Ratos Wistar , Substância Negra/citologia , Fatores de Tempo
20.
Neuroscience ; 73(1): 161-9, 1996 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8783239

RESUMO

Cell surface molecules, NCAM and L1, reported to have a role in synaptogenesis, growth and fasciculation of the neurites in the brain, were traced in the embryonic nigral transplants in the host striatum of adult rats. Substantia nigra of five, 15 and 25 postnatal days were also examined for the same molecules. Tyrosine hydroxylase label was used as a marker to localize the nigral neurons and glial fibrillary acidic protein to detect if glial scar present. In the control as well as transplants large neurons had expressed tyrosine hydroxylase. By 15th postnatal day tyrosine hydroxylase neurons appeared mature and were scattered, suggesting a well-formed neuropil. NCAM and L1 reaction was seen as a peripheral rim in most of the cells on the fifth postnatal day. The reaction was mainly in relation to the large cells and more extensive on the 15th day. Thereafter on the 25th day, activity was negligible. Large neurons demonstrated strong reactivity for NCAM and L1 during early post-transplantation days. After 30 days only smaller cells were reactive, many of which could be identified as neurons. Strong reaction for these molecules was present only until 60 days, though faint reaction could be detected even on the 90th day. These observations indicate that the growth promoting molecules, the type seen in the neonatal period, can be detected normally only until the neurons mature. Prolonged expression of these molecules by the grafted neurons indicate delay in the maturation of these cells due to absence of adequate target sites for synaptic connections. Some of the smaller cells expressing these molecules after 30 days of transplantation could be astroglia, either proliferating or reactive.


Assuntos
Antígenos de Superfície/metabolismo , Transplante de Tecido Encefálico/fisiologia , Transplante de Tecido Fetal/fisiologia , Mesencéfalo/metabolismo , Mesencéfalo/transplante , Neostriado/metabolismo , Moléculas de Adesão de Célula Nervosa/metabolismo , Animais , Proteína Glial Fibrilar Ácida/biossíntese , Imuno-Histoquímica , Complexo Antígeno L1 Leucocitário , Neostriado/citologia , Vias Neurais/crescimento & desenvolvimento , Vias Neurais/metabolismo , Vias Neurais/fisiologia , Ratos , Ratos Wistar , Substância Negra/citologia , Substância Negra/metabolismo , Tirosina 3-Mono-Oxigenase/metabolismo
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