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1.
Zhonghua Yi Xue Za Zhi ; 103(14): 1035-1041, 2023 Apr 11.
Article in Chinese | MEDLINE | ID: mdl-37032153

ABSTRACT

Objective: To investigate the effects of calorie-restricted diet (CRD), high protein diet (HPD), high protein, and high dietary fiber diet (HPD+HDF) on metabolic parameters and androgen level in overweight/obese patients with polycystic ovary syndrome(PCOS). Methods: Ninety overweight/obese patients with PCOS from Peking University First Hospital from October 2018 to February 2020 were given medical nutrition weight loss therapy for 8 weeks and were randomly divided into CRD group, HPD group, and HPD+HDF group, with 30 patients in each group. Body composition, insulin resistance, and androgen level were detected before and after weight loss, and the efficacy of three weight loss therapies was compared through variance analysis and Kruskal-Wallis H test. Results: Eight patients in CRD group quit because they could not strictly complete the follow-up, therefore at the end of weight loss, 22, 30, and 30 patients in CRD group, HPD group and HPD+HDF group, respectively, were included in the final analysis. The baseline ages of the three groups were (31±2) years, (32±5) years and (31±5) years, respectively (P=0.952). After weight loss, the relevant indicators in HPD group and HPD+HDF group decreased more than those in CRD group. The body weight of CRD group, HPD group and HPD+HDF group decreased by 4.20 (11.92, 1.80), 5.00 (5.10, 3.32) and 6.10 (8.10, 3.07) kg, respectively (P=0.038); BMI of the three groups decreased by 0.80 (1.70, 0.40), 0.90 (1.23, 0.50) and 2.20 (3.30, 1.12) kg/m2, respectively (P=0.002); homeostatic model assessment-insulin resistance(HOMA-IR) index decreased by 0.48(1.93, 0.05), 1.21(2.91, 0.18) and 1.22(1.75, 0.89), respectively (P=0.196); and free androgen index(FAI) decreased by 0.23(0.67, -0.04), 0.41(0.64, 0.30) and 0.44(0.63, 0.24), respectively (P=0.357). Conclusions: The three medical nutrition therapies can effectively reduce the weight of overweight/obese patients with PCOS, and improve insulin resistance and hyperandrogenism. Compared with CRD group, HPD group, and HPD+HDF group have better fat-reducing effect, and can better preserve muscle and basal metabolic rate while losing weight.


Subject(s)
Insulin Resistance , Polycystic Ovary Syndrome , Female , Humans , Adult , Overweight/therapy , Polycystic Ovary Syndrome/therapy , Polycystic Ovary Syndrome/metabolism , Androgens , Insulin/metabolism , Body Mass Index , Obesity/therapy , Weight Loss
2.
J Neurosci ; 19(22): 10053-64, 1999 Nov 15.
Article in English | MEDLINE | ID: mdl-10559413

ABSTRACT

Mossy fiber reorganization has been hypothesized to restore inhibition months after kainate-induced status epilepticus. The time course of recovery of inhibition after kainate treatment, however, is not well established. We tested the hypothesis that if inhibition is decreased after kainate treatment, it is restored within the first week when little or no mossy fiber reorganization has occurred. Chronic in vivo recordings of the septal dentate gyrus were performed in rats before and 1, 4, and 7-8 d after kainate (multiple injections of 5 mg/kg, i.p.; n = 17) or saline (n = 11) treatment. Single and paired-pulse stimuli were used to assess synaptic inhibition. The first day after kainate treatment, only a fraction of rats showed multiple population spikes (35%), prolonged field postsynaptic potentials (76%), and loss of paired-pulse inhibition (29%) to perforant path stimulation. Thus, inhibition was reduced in only some of the kainate-treated rats. By 7-8 d after treatment, nearly all kainate-treated rats showed partial or full recovery in these response characteristics. Histological analysis indicated that kainate-treated rats had a significant decrease in the number of hilar neurons compared to controls, but Timm staining showed little to no mossy fiber reorganization. These results suggest that a decrease in synaptic inhibition in the septal dentate gyrus is not a prerequisite for epileptogenesis and that most of the recovery of inhibition occurs before robust Timm staining in the inner molecular layer.


Subject(s)
Dentate Gyrus/physiopathology , Epilepsy/physiopathology , Animals , Dentate Gyrus/pathology , Dentate Gyrus/physiology , Electroencephalography , Epilepsy/chemically induced , Epilepsy/pathology , Excitatory Postsynaptic Potentials/physiology , Functional Laterality , Kainic Acid , Male , Neurons/pathology , Neurons/physiology , Perforant Pathway/pathology , Perforant Pathway/physiology , Perforant Pathway/physiopathology , Rats , Rats, Sprague-Dawley , Time Factors
3.
J Physiol ; 512 ( Pt 1): 149-62, 1998 Oct 01.
Article in English | MEDLINE | ID: mdl-9729625

ABSTRACT

1. Whole-cell voltage-clamp recordings in an in vitro brainstem-cranial nerve explant preparation were used to assess the local circuitry activated by vagal input to nucleus tractus solitarii (NTS) neurones in immature rats. 2. All neurones that responded to vagal stimulation displayed EPSCs of relatively constant latency. Approximately 50 % of these also demonstrated variable-latency IPSCs, and approximately 31 % also displayed variable-latency EPSCs to vagal stimulation. All neurones also had spontaneous EPSCs and IPSCs. 3. Evoked and spontaneous EPSCs reversed near 0 mV and were blocked by the glutamate AMPA/kainate receptor antagonists 6,7-nitroquinoxaline-2,3-dione (DNQX) or 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX) at rest. Evoked EPSCs had rapid rise times (< 1 s) and decayed monoexponentially (tau = 2. 04 +/- 0.03 ms) at potentials near rest. 4. At holding potentials positive to approximately -50 mV, a slow EPSC could be evoked in the presence of DNQX or CNQX. This current peaked at holding potentials near -25 mV and was blocked by the NMDA receptor antagonist DL-2-amino-5-phosphonovaleric acid (AP5). It was therefore probably due to activation of NMDA receptors by vagal afferent fibres. 5. Fast IPSCs reversed near -70 mV and were blocked by the GABAA receptor antagonist bicuculline. In addition, bicuculline enhanced excitatory responses to vagal stimulation and increased spontaneous EPSC frequency. Antagonists to AMPA/kainate receptors reversibly blocked stimulus-associated IPSCs and also decreased the frequency of spontaneous IPSCs. 6. These findings suggest that glutamate mediates synaptic transmission from the vagus nerve to neurones in the immature NTS by acting at non-NMDA and NMDA receptors. NTS neurones may also receive glutamatergic and GABAergic synaptic input from local neurones that can be activated by vagal input and/or regulated by amino acid inputs from other brainstem neurones.1. Whole-cell voltage-clamp recordings in an in vitro brainstem-cranial nerve explant preparation were used to assess the local circuitry activated by vagal input to nucleus tractus solitarii (NTS) neurones in immature rats.


Subject(s)
Brain Stem/physiology , Cranial Nerves/physiology , Evoked Potentials/physiology , Neurons/physiology , Solitary Nucleus/physiology , Synaptic Transmission/physiology , 2-Amino-5-phosphonovalerate/pharmacology , 6-Cyano-7-nitroquinoxaline-2,3-dione/pharmacology , Animals , Electric Stimulation , Evoked Potentials/drug effects , Excitatory Amino Acid Antagonists/pharmacology , Neurons/drug effects , Organ Culture Techniques , Patch-Clamp Techniques , Quinoxalines/pharmacology , Rats , Rats, Sprague-Dawley , Reaction Time , Synaptic Transmission/drug effects , Vagus Nerve/physiology
4.
J Neurosci ; 18(1): 184-94, 1998 Jan 01.
Article in English | MEDLINE | ID: mdl-9412499

ABSTRACT

During development, growth cones navigate to their targets via numerous interactions with molecular guidance cues, yet the mechanisms of how growth cones translate guidance information into navigational decisions are poorly understood. We have examined the role of intracellular Ca2+ in laminin (LN)-mediated growth cone navigation in vitro, using chick dorsal root ganglion neurons. Subsequent to contacting LN-coated beads with filopodia, growth cones displayed a series of stereotypic changes in behavior, including turning toward LN-coated beads and a phase of increased rates of outgrowth after a pause at LN-coated beads. A pharmacological approach indicated that LN-mediated growth cone turning required an influx of extracellular Ca2+, likely in filopodia with LN contact, and activation of calmodulin (CaM). Surprisingly, fluorescent Ca2+ imaging revealed no LN-induced rise in intracellular Ca2+ in filopodia attached to their parent growth cone. However, isolation of filopodia by laser-assisted transection unmasked a rapid, LN-specific rise in intracellular Ca2+ (+73 +/- 11 nM). Additionally, a second, sustained rise in intracellular Ca2+ (+62 +/- 8 nM) occurred in growth cones, with a distinct delay 28 +/- 3 min after growth cone filopodia contacted LN-coated beads. This delayed, sustained Ca2+ signal paralleled the phase of increased rates of outgrowth, and both events were sensitive to the inhibition of Ca2+/CaM-dependent protein kinase II (CaM-kinase II) with 2 microM KN-62. We propose that LN-mediated growth cone guidance can be attributed, in part, to two temporally and functionally distinct Ca2+ signals linked by a signaling cascade composed of CaM and CaM-kinase II.


Subject(s)
Calcium/metabolism , Laminin/pharmacology , Neurites/physiology , Neurons/enzymology , Second Messenger Systems/physiology , Animals , Calcium-Calmodulin-Dependent Protein Kinase Type 2 , Calcium-Calmodulin-Dependent Protein Kinases/metabolism , Chelating Agents/pharmacology , Chick Embryo , Egtazic Acid/analogs & derivatives , Egtazic Acid/pharmacology , Fura-2 , Ganglia, Spinal/cytology , Microscopy, Video , Microspheres , Neurites/drug effects , Neurons/ultrastructure , Time Factors
5.
J Inorg Biochem ; 65(2): 145-9, 1997 Feb 01.
Article in English | MEDLINE | ID: mdl-9014345

ABSTRACT

In order to clarify the relation between the reactivity of the leaving groups in cisplatin-like complexes and their activity / toxicity, six new complexes of the formula Pt(NH3)2X and Pt(dach)X (where X is selenato, anion of squaric acid, or demethylcantharic acid) have been synthesized and compared. These complexes have been characterized by elemental analysis, infrared spectroscopy, and conductivity measurements. Six human neoplastic cell lines (HCT, KB, BGC, HL-60, K-563 and Bel-7402) were used to screen these compounds. The results demonstrated that four of them have comparable IC50 and even lower IC50 in a few kinds of tumor cell lines compared to cisplatin. Their LD50 values showed that the toxicity of these platinum complexes is related to the reactivity of the leaving groups. All of these complexes have lower acute toxicity than cisplatin, but the anticancer activity is not affected.


Subject(s)
Antineoplastic Agents/pharmacology , Antineoplastic Agents/toxicity , Cisplatin/analogs & derivatives , Organoplatinum Compounds/pharmacology , Organoplatinum Compounds/toxicity , Actins/chemistry , Actins/pharmacology , Animals , Antineoplastic Agents/chemical synthesis , Cisplatin/pharmacology , Cisplatin/toxicity , Drug Screening Assays, Antitumor , Electric Conductivity , Humans , In Vitro Techniques , Lethal Dose 50 , Mice , Organoplatinum Compounds/chemical synthesis , Rabbits , Spectrophotometry , Structure-Activity Relationship , Sulfhydryl Compounds/chemistry , Tumor Cells, Cultured
6.
J Neurobiol ; 31(1): 1-15, 1996 Sep.
Article in English | MEDLINE | ID: mdl-9120430

ABSTRACT

Previous findings indicate that spatial restriction of intracellular calcium levels within growth cones can regulate growth cone behavior at many levels, ranging from filopodial disposition to neurite extension. By combining techniques for focal stimulation of growth cones with those for measurement of filopodia and for capturing low intensity calcium signals, we demonstrate that filopodia on individual growth cones can respond to imposed stimuli independently from one another. Moreover, filopodia and their parent growth cones appear to represent functionally and morphologically distinct domains of calcium regulation, possessing distinct calcium sources and sinks. Both are sensitive to calcium influx; however, application of the calcium ionophore A23187 to cells in calcium-free medium demonstrated the presence of potential intracellular calcium pools in the growth cone proper, but not in isolated filopodia. Thapsigargin significantly reduced the rise in growth cone calcium levels associated with excitatory neurotransmitters, further implicating release from calcium pools as one component of growth cone calcium regulation. The relative contributions of these pools were examined in response to excitatory neurotransmitters by quantitative calcium measurements made in both growth cones and isolated filopodia. Striking differences were observed; filopodia were sensitive to a low concentration of dopamine and serotonin, while growth cones displayed an amplified rise at a higher concentration. The spatial distribution of organelles that could serve as morphological correlates to such calcium amplification was examined using confocal microscopy. While the majority of organelles were located in the central core of the growth cone proper, peripheral organelles were detected at the base of a subset of filopodia. The distinctive distribution of calcium regulation within motile growth cones suggests one mechanism by which growth cones may regulate their complex behavior.


Subject(s)
Calcium/metabolism , Neurites/physiology , Neurons/physiology , Sense Organs/physiology , Signal Transduction/physiology , Animals , Calcimycin/pharmacology , Cells, Cultured , Dopamine/pharmacology , Ionophores/pharmacology , Neurites/drug effects , Neurons/drug effects , Neurons/ultrastructure , Sense Organs/drug effects , Serotonin/pharmacology , Signal Transduction/drug effects , Snails , Thapsigargin/pharmacology
7.
J Neurobiol ; 27(2): 127-40, 1995 Jun.
Article in English | MEDLINE | ID: mdl-7658196

ABSTRACT

Although it is becoming increasingly clear that structural dynamics on neurite shafts play important roles in establishing neuronal architecture, the underlying mechanisms are unknown. The present study investigates local induction of filopodia along the shafts of neurites, a process that, by analogy to the growth cone, can represent the first stage in the generation of a new neuronal process. We show that filopodia can be induced reliably along the neurite shaft in response to a localized electric field stimulus that evokes large local intracellular calcium increases. Neither induction of filopodia nor a local rise in intracellular calcium occurred in calcium-free medium. Although calcium induction of neurite filopodia is highly reliable, forming in response to more than 90% of attempts, it is developmental state-dependent, since neurite filopodia could not be induced in neurons previously defined as "stable state." We have found two distinct changes in stable state neurons that can decrease the ability to induce new neurites. The first is a reduced calcium response: Field stimulation produced large local rises (280 nM) in intracellular calcium in growing neurons, whereas the identical stimulus produced smaller changes (148 nM) in stable state neurons. Second, stable state neurons change so that even when the stimulus intensity was increased to elicit a calcium response that would have been sufficient to induce filopodia in growing neurites, neurite filopodia were still not induced. Thus, intracellular calcium plays a key role in structural changes along the shafts of neurites. Furthermore, developmental changes in both calcium homeostatic components and in calcium responsiveness (i.e., the sensitivity of cellular components that modulate neurite morphology) underlie shifts from plasticity to stability of neuronal architecture in this system.


Subject(s)
Ganglia, Invertebrate/growth & development , Ganglia, Invertebrate/physiology , Neurites/physiology , Neuronal Plasticity/physiology , Snails/physiology , Animals , Calcium/metabolism , Cells, Cultured , Electric Stimulation , Fura-2 , Homeostasis/physiology , Microscopy, Electron , Microscopy, Phase-Contrast , Neurites/ultrastructure
8.
Nature ; 361(6414): 721-4, 1993 Feb 25.
Article in English | MEDLINE | ID: mdl-8441465

ABSTRACT

The dynamic nature of neuronal growth cone filopodia led to the suggestion that the primary function of filopodia is to sample their immediate environment, responding to and transducing environmental signals that affect growth cone behaviour and shape. Filopodia seem well suited to serve as antenna-like sensors, their broad span allows sampling of information over a greatly enhanced radius, and forward-projecting filopodia encounter potential cues in the molecular terrain long before the advancing growth cone itself. Filopodia in culture can serve structural roles, exert mechanical tension and selectively adhere to their surrounding. Whether or not filopodia have a general sensory role has not been tested directly, largely because of their small size, which limits an electrophysiological approach, and their integral relationship with the parent growth cone, which prevents resolution of their different functions. Here we use surgical procedures to isolate individual filopodia from their parent growth cone and, by monitoring their morphology and calcium second messenger systems, we show that neuronal growth cone filopodia contain signal transduction mechanisms that allow autonomous responses and the transmission of distant environmental information to their parent growth cone.


Subject(s)
Neurons/physiology , Acetylcholine/pharmacology , Animals , Calcimycin/analogs & derivatives , Calcimycin/pharmacology , Calcium/metabolism , Electric Stimulation , Fura-2 , In Vitro Techniques , Kinetics , Models, Neurological , Neurons/drug effects , Neurons/ultrastructure , Serotonin/pharmacology , Snails
9.
J Neurosci ; 12(12): 4867-77, 1992 Dec.
Article in English | MEDLINE | ID: mdl-1464771

ABSTRACT

This study investigates the capacity of neuronal growth cones to synthesize protein locally and independently of their cell body. Isolated growth cones were prepared from cultures of neurons from the snail Helisoma by transecting neurites proximal to the growth cone. The capacity for protein synthesis was tested by radiolabeling cultures with 3H-leucine and analyzing the resultant autoradiograms. Isolated growth cones displayed incorporation of 3H-leucine that was inhibited by treatment with the protein synthesis inhibitors anisomycin and pactamycin, indicating that ribosomal-dependent translation occurs in growth cones. Ultrastructural analyses of growth cones demonstrated the presence of polyribosomes, the machinery for protein synthesis. The density of polyribosomes varied between growth cones, even between different growth cones on the same neuron, suggesting that growth cones express a range of protein synthetic capabilities. That different types of growth cones possess differing capabilities for protein synthesis is suggested in autoradiograms of 3H-leucine incorporation by the growth cones of axonal and nonaxonal neurites; incorporation was radically reduced in axonal growth cones in comparison with non-axonal growth cones. Finally, growth cones that were isolated for 2 d prior to radiolabeling incorporate 3H-leucine in a eukaryotic ribosomal-dependent manner, suggesting that the capacity for translation is long-lived in growth cones. Taken together, these studies reveal a capacity for protein synthesis confined totally to the neuronal growth cone proper. The synthesis of proteins in growth cones could afford a mechanism for the alteration of growth cone structure or function. This is in accord with the view that growth cones participate autonomously, to at least some extent, in the processes of synaptogenesis and the construction of neuronal architecture.


Subject(s)
Nerve Tissue Proteins/biosynthesis , Neurites/metabolism , Neurons/metabolism , Protein Synthesis Inhibitors/pharmacology , Animals , Anisomycin/pharmacology , Autoradiography , Cells, Cultured , Ganglia/metabolism , Helix, Snails , Kinetics , Leucine/metabolism , Microscopy, Electron , Neurites/drug effects , Neurites/ultrastructure , Neurons/drug effects , Neurons/ultrastructure , Pactamycin/pharmacology , Ribosomes/metabolism , Tritium
10.
J Neurobiol ; 22(5): 499-511, 1991 Jul.
Article in English | MEDLINE | ID: mdl-1890426

ABSTRACT

This study examines the capability of growth cones from identified neurons of the snail Helisoma trivolvis to perform calcium homeostasis. Calcium influx into the cytoplasm was eliminated or increased experimentally to alter [Ca]i, and the compensatory response of the growth cone was measured with the fluorescent calcium indicator Fura-2. Growth cones compensated for both increases and decreases in calcium influx by restoring [Ca]i towards basal levels under both types of challenges. The intrinsic ability of growth cones to control [Ca]i was examined in physically isolated growth cones. Isolated growth cones demonstrated essentially identical calcium homeostatic properties to their intact counterparts, indicating that mechanisms governing calcium homeostasis exist intrinsically in the growth cone. Such independence may add significantly to the growth cone's potential to locally interpret and respond to stimuli encountered en route to its appropriate target.


Subject(s)
Calcium/physiology , Homeostasis/physiology , Neurons/physiology , Snails/physiology , Animals , Calcimycin/pharmacology , Cells, Cultured , Fura-2 , Homeostasis/drug effects , Neurons/drug effects
11.
Chin Med J (Engl) ; 102(11): 844-50, 1989 Nov.
Article in English | MEDLINE | ID: mdl-2517725

ABSTRACT

Phagaquosonographies (PASG) of 100 normal subjects and 223 patients with cardiac cancer (CC) were analyzed. The apparatus was self-designed and self-manufactured. The wave patterns and the pre-ejection period and other 8 quantitative indices in PASG were compared and patients with CC were found to have abnormal levels (P less than 0.01). The phagaquosonograms in 82 patients with esophageal, gastric or cardias (non-cancer) diseases served as controls. The PASG showed positive results in 97.3%, suspicious in 2.3% and negative in 0.4% of CC cases and 100% negative in the normal subjects. It was 1.2% positive, 8.5% suspicious and 90.3% negative in the esophageal, cardiac or gastric non-cancer diseases. PASG has high sensitivity (97.3%), and typical characteristics (98.8%). It is shown that this method can be used in screening, diagnosis, differential diagnosis and prediction of prognosis of cardiac cancer.


Subject(s)
Electrodiagnosis/methods , Stomach Neoplasms/diagnosis , Aged , Cardia , Deglutition , Humans , Middle Aged , Sound Spectrography/methods , Water
12.
J Neurosci ; 8(6): 2087-100, 1988 Jun.
Article in English | MEDLINE | ID: mdl-2898515

ABSTRACT

The present study examined the effects of glutamate on the outgrowth of dendrites and axons in isolated hippocampal pyramidal-like neurons in cell culture. During the first day of culture the survival and outgrowth of these neurons was unaffected by high concentrations (up to 1 nM) of glutamate, quisqualic acid (QA), kainic acid (KA), and N-methyl-D-aspartic acid. Beginning on day 2 of culture high levels of glutamate, KA and QA were toxic to the majority of pyramidal neurons, while subtoxic levels of these agents caused a well-defined, dose-dependent, sequence of effects on dendritic outgrowth. At increasing concentrations of glutamate, QA, and KA, the following events were observed: (1) dendritic outgrowth rates were reduced, while axonal elongation rates were unaffected; (2) dendritic length was reduced, while axons continued to grow; (3) dendrites regressed dramatically, and axonal outgrowth rate was reduced. These dendrite-specific effects of glutamate were apparently mediated at the growth cones since focal application of glutamate to individual dendritic growth cones resulted in suppression of growth cone activity and a regression of the dendrite; axons were unaffected by focal glutamate application. Pharmacological tests using glutamate receptor agonists and antagonists demonstrated that receptors of the KA/QA type mediated the glutamate effects on outgrowth and survival. The calcium channel blocker Co2+ prevented both glutamate neurotoxicity and glutamate-induced dendritic regression. Ionophore A23187 and elevations in extracellular K+ levels each caused a dose-dependent series of outgrowth and survival responses similar to those caused by glutamate. Taken together, these results indicate that activation of glutamate receptors leads to the opening of voltage-dependent calcium channels; the resulting increases in calcium influx lead to the observed alterations in dendritic outgrowth and neuronal survival.


Subject(s)
Glutamates/pharmacology , Hippocampus/cytology , Neurons/drug effects , Animals , Axons/physiology , Axons/ultrastructure , Calcium/metabolism , Calcium/physiology , Cell Separation , Cell Survival/drug effects , Dendrites/physiology , Dendrites/ultrastructure , Glutamic Acid , Hippocampus/physiology , Hippocampus/ultrastructure , Neurons/physiology , Neurons/ultrastructure , Receptors, Glutamate , Receptors, Neurotransmitter/metabolism
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