Biomedical subjects

Z Sheng

Publications and source records attributed to Z Sheng.

At least 73 records · Page 4Linked to original sources

PubMed1998

[The significance of changes in serum soluble lipopolysaccharide receptor CD14 levels in burned patients with multiple organ dysfunction syndrome].

OBJECTIVE: To determine whether an increased soluble lipopolysaccharide receptor CD14 (sCD14) level is associated with the development of multiple organ dysfunction syndrome (MODS) in patients after major burns. METHOD: 22 patients with burns covering more than 70% of body surface area were studied. These patients were divided into two groups according to the occurrence of MODS (MODS group, n = 9; non-MODS group, n = 13). Blood samples were obtained from burned patients. Serum concentrations of sCD14 and tumor necrosis factor (TNF) were determined by sandwich ELISA. Plasma endotoxin was measured using a quantitative chromogenic LAL test. RESULT: Compared to the healthy volunteers, a significant increase in serum sCD14 levels was observed in 22 patients on day 7 postburn, which remained marked elevation up to 21 days after thermal insult (P < 0.01). The serum sCD14 levels of the MODS group were significantly higher than those of the non-MODS group on days 7, 14, and 21 postburn (P < 0.05). Additionally, the serum sCD14 and endotoxin levels were positively correlated in patients who developed MODs on days 7, 14 and 21 postburn (P < 0.05), whereas no correlation was found between sCD14 and TNF levels at any time point (P > 0.05). CONCLUSION: Our data suggest that sCD14 elevation is associated with the development of MODS after major burns, and endotoxin release may be involved in the activation of sCD14 under certain pathophysiological conditions.

Adolescent↗

PubMed1997

Evidence for interaction between transmembrane segments in assembly of Kv1.3.

Previously, we showed that the N-terminal recognition domain (T1) of Kv1.3 was not required for assembly of functional channels [Tu et al. (1996) J. Biol. Chem. 271, 18904-18911]. Moreover, specific Kv1.3 peptide fragments including regions of the central core are able to inhibit expression of current produced from a channel lacking the T1 domain, Kv1.3(T1-). To elucidate the mechanism whereby Kv1.3 peptide fragments suppress Kv1.3(T1-) current, we have studied the ability of peptide fragments containing the transmembrane segments S1, S1-S2, or S1-S2-S3 to physically associate with the Kv1.3(T1-) polypeptide subunit in vitro in microsomal membranes. Using c-myc (9E10) epitope-labeled peptide fragments and anti-myc antibody as well as antisera to the Kv1.3 C-terminus, we now demonstrate specific association of these peptide fragments with Kv1.3(T1-). Association of peptide fragments with Kv1.3(T1-) was correlated with integration of both proteins into the membrane. Furthermore, the relative strength and kinetics of this association directly correlated with the ability of fragments to suppress Kv1.3(T1-) current. The rate-limiting step in the sequential synthesis, integration, and formation of a complex was the association of integrated polypeptides within the plane of the lipid bilayer. These results strongly suggest that the physical association of transmembrane segments provides the basis for suppression of K+ channel function by K+ channel peptide fragments in vivo. Moreover, the S1-S2-S3 peptide fragment potently suppressed full-length Kv1.3, thus implicating a role for the S1-S2-S3 region of Kv1.3 in the assembly of the Kv1.3 channel. We refer to these putative association sites as IMA (intramembrane association) sites.

Amino Acid Sequence↗

PubMed1997

Cardiotrophin 1 (CT-1) inhibition of cardiac myocyte apoptosis via a mitogen-activated protein kinase-dependent pathway. Divergence from downstream CT-1 signals for myocardial cell hypertrophy.

Cardiac myocyte survival is of central importance in the maintenance of the function of heart, as well as in the development of a variety of cardiac diseases. To understand the molecular mechanisms that govern this function, we characterized apoptosis in cardiac muscle cells following serum deprivation. Cardiotrophin 1 (CT-1), a potent cardiac survival factor (Sheng, Z., Pennica, D., Wood, W. I., and Chien, K. R. (1996) Development (Camb.) 122, 419-428), is capable of inhibiting apoptosis in cardiac myocytes. To explore the potential downstream pathways that might be responsible for this effect, we documented that CT-1 activated both signal transducer and activator of transcription 3 (STAT3)- and mitogen-activated protein (MAP) kinase-dependent pathways. The transfection of a MAP kinase kinase 1 (MEK1) dominant negative mutant cDNA into myocardial cells blocked the antiapoptotic effects of CT-1, indicating a requirement of the MAP kinase pathway for the survival effect of CT-1. A MEK-specific inhibitor (PD098059) (Dudley, D. T., Pang, L., Decker, S.-J., Bridges, A. J., and Saltiel, A. R. (1995) Proc. Natl. Acad. Sci. USA 92, 7686-7689) is capable of blocking the activation of MAP kinase, as well as the survival effect of CT-1. In contrast, this inhibitor did not block the activation of STAT3, nor did it have any effect on the hypertrophic response elicited following stimulation of CT-1. Therefore, CT-1 promotes cardiac myocyte survival via the activation of an antiapoptotic signaling pathway that requires MAP kinases, whereas the hypertrophy induced by CT-1 may be mediated by alternative pathways, e.g. Janus kinase/STAT or MEK kinase/c-Jun NH2-terminal protein kinase.

Animals↗

PubMed1997

Basic fibroblast growth factor reduces the gut and liver morphologic and functional injuries after ischemia and reperfusion.

OBJECTIVE: To explore the possible effects of basic fibroblast growth factor (bFGF) on ischemic gut and liver injuries after trauma. METHODS: Animal models of superior mesenteric artery occlusion (45 minutes) and reperfusion (3 days) were used in this study. Seventy-two Wistar rats were divided into three groups of 24 rats each. The animals in bFGF-treated group were injected with 4 microg bFGF/rat in 0.15 mL normal saline solution containing heparin 0.1% (w/v) through the jugular vein at the onset of reperfusion. In the normal saline control group, all rats received the same vehicle, but without bFGF. Group 3 (sham-operated) underwent the same laparotomy procedure, but without superior mesenteric artery occlusion. Liver function parameters, the levels of serum tumor necrosis factor alpha, nitric oxide, superoxide dismutase, malondialdehyde (MDA), tissue bacterial examination, and pathologic study were used to evaluate the results. RESULTS: In bFGF-treated rats, the amounts of serum alanine transaminase and aspartate aminotransferase and serum tumor necrosis factor-alpha were reduced significantly at 6, 24, and 48 hours when compared with normal saline-treated rats. However, the changes in nitric oxide, superoxide dismutase, and MDA varied from each other as a function of time after injury. The amounts of nitric oxide were increased significantly at 6 hours in intestine in normal saline-treated rats and in liver in bFGF-treated rats (p < 0.05). At 6 hours after reperfusion, the activity of superoxide dismutase in normal saline-treated rats were much lower in liver than those in bFGF-treated and sham-operated rats (p < 0.05), but the levels of MDA were increased in intestine in bFGF-treated rats and in liver in normal saline-treated rats when compared with sham-operated rats (p < 0.05). At 24 hours, the levels of MDA in normal saline-treated rats were much higher than those in both bFGF and sham-operated rats (p < 0.05). Bacterial examination revealed that the ratio and the amounts of bacterial translocation from gut to liver, spleen, and mesenteric lymph nodes in bFGF-treated rats were much lower than those in normal saline-treated rats. The results of pathologic study support the assumption that bFGF provided protective effects against reperfusion injury. CONCLUSIONS: Intravenous administration of bFGF may benefit in reducing gut and liver injuries after ischemia and reperfusion. The mechanisms of those effects may involve mitogenic and nonmitogenic effects of bFGF.

Animals↗

PubMed1997

[Measurement of urinary content of lactulose and mannitol by gas chromatography as an index of permeability of the gut].

We established lactulose-mannitol(L-M) measurement method by gas chromatography and 9202 computer data processing system to test intestinal permeability. The urine output of L-M was in linear correlation to its sample concentration within working range. In an animal model of acute pancreatitis, lactulosesecretion increased in urine, together with increased L/M ratio. The measurement of lactulose-mannitol intestinal permeability by our method might serve as a predictor for early diagnosis of endogenous infection and sepsis.

Animals↗

PubMed1997

[The relationship between abnormalities of cell-mediated immunity and gut origin endotoxemia in a rat model of thermal injury].

This study was conducted to determine the relationship between abnormalities of cell-mediated immunity and gut-derived endotoxemia in rats following burns. Animals were subjected to a 40% full-thickness scald injury, and randomly divided into control and selective decontamination of the digestive tract (SDD) treated groups. It was found that thermal injury resulted in marked reductions in splenocyte proliferative response to concanavalin A or phytohemagglutinin, interleukin 2 (IL-2) production, and T helper/suppressor (Th/Ts) cells ratio. Prophylactic treatment with SDD significantly reduced the incidence of endotoxemia, prevented suppressive mitogenic response and inadequacy in IL-2 production (P < 0.05-0.01), but did not affect the abnormal ratio of Th/Ts in blood (P > 0.05). We conclude that bacteria/endotoxin translocation from the gastrointestinal tract appears to be involved in cellular immune dysfunction after thermal injury. Pretreatment with SDD might attenuate systemic immunosuppression by preventing translocation events.

Animals↗

PubMed1997

[Serum neopterin levels after extensive burns and their relationship to endotoxemia and sepsis].

The present study was performed to determine the kinetics of serum neopterin levels after major thermal injury and their relationship to endotoxemia and sepsis. This prospective study included 35 patients (32 males and three females) with total burn surface area (TBSA) greater than 30% (30%-98%), and 22 healthy volunteers who served as normal controls. The results showed that neopterin levels increased in most patients on day 3 postburn, but they were not significantly correlated with the extent of the burn surface (P > 0.05). Patients with endotoxemia had much higher neopterin values than those who showed no endotoxemia from the second week onward (P < 0.05-0.01), and circulating endotoxin and neopterin levels were positively correlated in patients who developed endotoxemia on day 14 (r = 0.368, P < 0.05) and day 21 (r = 0.439, P < 0.01) after major burns. Moreover, a high serum neopterin level was found in patients with sepsis (n = 15), and the marked elevation persisted throughout the observation period. The difference between septic and non-septic patients (n = 20) became significant on 14 and 28 days postburn. These data suggest that extensive burns can lead to an elevation of serum neopterin independent of TBSA. The endotoxin release in the circulation may be involved in the continuous formation of neopterin during the late postburn stage. In addition, the presence of a constant high neopterin level is associated with a critical event in the development of burn sepsis.

Adolescent↗

PubMed1997

[Effect of recombinant bactericidal/permeability-increasing protein on pulmonary cytokine mRNA expression in rats following hemorrhage and resuscitation].

To determine the possible mechanisms underlying beneficial effect of recombinant bactericidal/permeability-increasing protein (rBPI) on acute lung injury response to blood loss, we used reverse transcription polymerase chain reaction to measure pulmonary tumor necrosis factor (TNF), interleukin 6 (IL-6) mRNA expression in a rat model of prolonged hemorrhagic shock (4.00 kPa, 180 min) followed by adequate resuscitation. The results showed that systemic plasma endotoxin concentrations elevated rapidly after a 180-min hemorrhagic insult (P < 0.05), and TNF, IL-6 mRNA expression in the lung were significantly increased at 2, 8 hours after resuscitation respectively. However, treatment with rBPI resulted in almost neutralization of plasma endotoxin values, remarkable reduction of TNF, IL-6 mRNA levels following hemorrhage/resuscitation. Also, it was found that rBPI administration markedly blunted the increase in pulmonary Evans blue dye extravasation, concomitant with a significant decrease in lung myeloperoxidase activity compared with the control group (P < 0.05-0.01). These data suggest that local proinflammatory cytokine mRNA expression associated with gut origin endotoxemia may be an important mechanism contributing to the development of hemorrhage-induced lung injury. Treatment with rBPI is effective in inhibiting marked TNF, IL-6 mRNA expression and ameliorating acute lung injury secondary to severe hemorrhagic shock.

Animals↗

PubMed1997

[Water vapor permeability measurement of the materials used as a wound covering].

This paper introduces a new apparatus and method that suits to measuring the water vapor transmission rate (WVTR) of wound covering materials. WVTR of synthetic materials, amniotic membrane, porcine and cadaveric skin was measured under different conditions of four temperatures, three mediums, and "water cup" or "inverted water cup". The temperature was in close relationship with the WVTR except Omiderm, amniotic membrane, and cadaveric skin between 30 degrees C and 37 degrees C groups. The medium did not affect the WVTR (P > 0.05). There was significant difference between the "water cup" and "inverted water cup" groups(P < 0.01). This study suggests that the apparatus is easy-to-operate, reliable and suitable for the measurement of WVTR of burn wound coverings and other membranous materials.

Bandages↗

PubMed1997

[Study on transposition behavior of IS5376 in Bacillus stearothermophilus].

IS5376 and IS5377 are two transposable elements discovered in Bacillus stearothermophilus. Analysis of random samples revealed that the frequency of transposition of IS5376 from CU21 chromosome to plasmids pFDC5 and pFDC12 was much higher at 65 degrees C than that at 48 degrees C while that of IS5377 was very low at both 48 degrees C and 65 degrees C. The exact nature of the temperature effect is obscure at present from evidences obtained so far it is concluded that this is a consequence of the innate property of IS5376. Furthermore, it was found that a certain degree of site specificity in transposition was evident and that a direct repeat of 4 or 5 bp of the target DNA appeared at the site of transposition.

Base Sequence↗

PubMed1997

Oxygen free radical injury and its relation to bacterial and endotoxin translocation after delayed fluid resuscitation: clinical and experimental study.

OBJECTIVE: To examine whether there is generation of oxygen free radicals (OFR) and lipid peroxidation of cell membrane after volume replacement for burn shock, and to study the relationship between OFR injury and enterogenous endotoxemia. METHODS: Forty-seven burn patients were involved in this study. Among them, 18 had delayed fluid resuscitation (DR) and the others had early fluid resuscitation (ER) within 6 hours postburn. Sixty-six gnotobiotic rats were used in a collaborating experiment as burn models. They were divided into 4 groups: sham injury (n = 6), early resuscitation (n = 24), late resuscitation (n = 24) and vitamins E and C treatment group (n = 12). All the rats, except those in the sham injury group, were inflicted with 40% total body surface area (TBSA) third-degree burns. OFR was determined in the blood of patients with electron spin resonance (ESR). S/W ratio and tau c values of patients' erythrocytes were measured with ESR spectrometer. Blood superoxide dismutase (SOD) and glutathione peroxidase (GSHPx) activities, malondialdehyde contents and plasma endotoxin levels were assayed. Rats were sacrificed at the 12th, 24th, 48th and 72nd hour after injury. Plasma endotoxin levels, mucosal SOD, GSHPx and malondialdehyde (MDA), as well as diamine oxidase activity of ileum were determined. Cultures of mesenteric lymph nodes (MLN), liver, spleen, heart, lung, kidney and blood were done. RESULTS: A significant increase in blood OFR contents and plasma MDA, and a significant decline in blood SOD and GSHPx were found after resuscitation in DR group as compared with those in ER group. Both strong to weak spectra component (S/W) ratio and tau c value were higher in DR group in contrast with those in ER group. Higher elevation in plasma endotoxin level in DR group was seen. In DR group, plasma MDA content was correlated with S/W ratio, tau c value and plasma endotoxin level. In rats, the level of mucosal MDA, plasma endotoxin and incidence of bacterial translocation (BT) were significantly higher. Mucosal SOD, GSHPx and diamine oxidase (DAO) activity were significantly lower in DR group as compared with those in ER group. In DR group, mucosal MDA content was negatively correlated with mucosal DAO activity, while the latter was negatively correlated with BT. After treatment with vitamins E and C, mucosal MDA content decreased, plasma endotoxin and BT significantly declined and mucosal DAO heightened. CONCLUSIONS: Tissue reperfusion might induce the production of OFR, resulting in lipid peroxidation injury, especially to intestinal mucosa, and resulting in disruption of mucosal barrier function followed by endotoxemia and BT.

Adolescent↗

PubMed1997

The relationship between gut-derived endotoxemia and tumor necrosis factor, neopterin: experimental and clinical studies.

OBJECTIVE: To determine the relationship between gut-derived endotoxemia and tumor necrosis factor (TNF), neopterin/biopterin formation following hemorrhage, trauma and burns. METHODS: Rats were subjected to hemorrhagic shock (30 mmHg, 90-180 min) and 40% III degrees thermal injury. Circulating endotoxin, TNF, biopterin levels and liver TNF mRNA expression were measured in animals following acute insults. Also, the subjects of this study included 35 patients with burn size greater than 30%, and 25 patients with multiple injuries (n = 18) and major surgery (n = 7). RESULTS: It was found that significant portal and systemic endotoxemia took place in the control animal after hemorrhagic shock and thermal injury, but almost not in the animals that treated by measures aiming at controlling endotoxin/bacteria translocation, including polymyxin B, monoclonal antibody against core lipopolysaccharide, and selective decontamination of the digestive tract (SDD). Concomitantly, hemorrhage and thermal injury resulted in significant increases in systemic plasma TNF level together with tissue TNF mRNA expression, which were associated with the initial appearance of endotoxin in portal vein. However, anti-endotoxin treatment markedly decreased circulating TNF level as well as peak TNF mRNA expression caused by acute insults. There were also lower serum biopterin values in the SDD-treated group as compared with the control group on day 5 postburn. On the other hand, the results showed that the amounts of plasma endotoxin in patients increased during the early stages following major burns, which was significantly correlated with plasma TNF levels, particularly in patients who developed sepsis and multiple organ failure. Although the presence of early endotoxemia did not influence the alterations in serum neopterin, patients with endotoxemia had much higher neopterin values than those who showed no endotoxemia from the second week onward. CONCLUSION: These results suggest that gut-derived endotoxemia could account, at least in part, for the inflammatory mediators formation and release, which might be involved in the pathogenesis of sepsis and multiple organ dysfunction following severe hemorrhage, trauma and burns.

Adult↗

PubMed1997

[Study on the cytotoxic and DNA damaging effects in oral mucosal fibroblasts by areca nut extract].

An aqueous areca nut extract (ANE) was tested for its cytotoxic effects on cultured human embryo oral mucosal fibroblasts (HE-OMF) in vitro by using the trypan blue and thiazolyl blue (MTT) assay. The ANE decreases the cell survival rate in a dose-dependent manner (P < 0.05). So was the extract in inducing damage on the cellular DNA of HE-OMF in vitro examined by the nick translation assay. The increase in counts per minute (CPM) values was significant (P < 0.05) for comparing all four concentration groups tested, The results suggests that aqueous ANE is highly cytotoxic and capable to induce DNA damage on cultured HE-OMF. It may have potential carcinogenic effect on the oral mucosal membrane of whom habitually chewing the areca nut frequently for quite a long time. Futher study is required to illustrate the detail process and study the mechanism of these effects.

Areca↗

PubMed1997

[The preventing function of garlic on experimental oral precancer and its effect on natural killer cells, T-lymphocytes and interleukin-2].

In order to study the effect and mechanism of garlic on preventing oral precancer, we divided randomly 32 Wistar rats into two groups. The garlic group was painted with garlic solution on the hard palatal mucosae. The control group was applied with distilled water that is equal in quantity. Then, chemical carinogen 4-nitroquinoline 1-oxide (4NQO) was painted on the same sites for both groups, three times weekly. Eight rats were randomly killed in the 10th, 13th week. The hard palatal mucosae were examined with light microscope. Meanwhile, lymphocytes were isolated from the rat spleens. The activation of natural killer (NK) cells and T-lymphocytes, and level of interleukin-2 were determined by radioimmunoassay. The results revealed that garlic effectively prevented oral precancer induced by 4NQO. This effect may be related to the following factors that garlic can improve the activation of NK cells, the function of T-lymphocytes, and the level of IL-2.

Animals↗

PubMed1996

Voltage-gated K+ channels contain multiple intersubunit association sites.

A domain in the cytoplasmic NH2 terminus of voltage-gated K+ channels supervises the proper assembly of specific tetrameric channels (Li, M., Jan, J. M., and Jan, L. Y.(1992) Science 257, 1225-1230; Shen, N. V., Chen X., Boyer, M. M., and Pfaffinger, P. (1993) Neuron 11, 67-76). It is referred to as a first tetramerization domain, or T1 (Shen, N. V., Chen X., Boyer, M. M., and Pfaffinger, P.(1993) Neuron 11, 67-76). However, a deletion mutant of Kv1.3 that lacks the first 141 amino acids, Kv1.3 (T1(-)) forms functional channels, suggesting that additional association sites in the central core of Kv1.3 mediate oligomerization. To characterize these sites, we have tested the abilities of cRNA Kv1.3 (T1(-)) fragments co-injected with Kv1.3 (T1(-)) to suppress current in Xenopus oocytes. The fragments include portions of the six putative transmembrane segments, S1 through S6, specifically: S1, S1-S2, S1-S2-S3, S2-S3, S2-S3-S4, S3-S4, S3-S4-S5, S2 through COOH, S3 through COOH, S4 through COOH, and S5-S6-COOH. Electrophysiologic experiments show that the fragments S1-S2-S3, S3-S4-S5, S2 through COOH, and S3 through COOH strongly suppress Kv1.3 (T1(-)) current, while others do not. Suppression of expressed current is due to specific effects of the translated peptide Kv1.3 fragments, as validated by in vivo immunoprecipitation studies of a strong suppressor and a nonsuppressor. Pulse-chase experiments indicate that translation of truncated peptide fragments neither prevents translation of Kv1.3 (T1(-)) nor increases its rate of degradation. Co-immunoprecipitation experiments suggest that suppression involves direct association of a peptide fragment with Kv1.3 (T1(-)). Fragments that strongly suppress Kv1.3 (T1(-)) also suppress an analogous NH2-terminal deletion mutant of Kv2.1 (Kv2.1 (DeltaN139)), an isoform belonging to a different subfamily. Our results indicate that sites in the central core of Kv1.3 facilitate intersubunit association and that there are suppression sites in the central core, which are promiscuous across voltage-gated K+ channel subfamilies.

Animals↗

PubMed1996

Human T-cell lymphotropic virus types I and II infections in patients with leukaemia/lymphoma and in subjects with sexually transmitted diseases in Nigeria.

Serological assays that distinguish antibodies to human T-cell lymphotropic virus types I (HTLV-I) and type II (HTLV-II), and polymerase chain reaction (PCR) tests were used to investigate association of these two human retroviruses with several well-defined clinical conditions in Nigeria. We compared the frequency of HTLV-I and HTLV-II infections among patients with lymphopholiferative disorders (n=65), individuals with various sexually transmitted diseases (n=40), patients with genitals candidiasis (n=25) and apparently healthy individuals (n=60). Serological analysis of blood samples from all four groups showed that 10 of the 190 (5.3%) individuals tested were confirmed positive for the presence of antibodies to HTLV-I(6) or HTLV-II(4). Using the PCR technique, specific HTLV-I or HTLV-II sequences were amplified from the genomic DNA of 4 of 6 HTLV-I seropositive and 3 of the 4 HTLV-II seropositive individuals respectively. However, sequences of both viruses were amplified from the genomic DNAs of the remaining 3 seropositive individuals. Since one of the 5 sets of primer pairs [SK110(II)/SK111(II)], which is used for specific identification of HTLV-II did not amplify the target sequence from the genomic DNAs of any of the 4 HTLV-II confirmed seropositive individuals in this study, it suggested sequence diversity of these viruses in Nigeria. The virus-infected individuals identified in this study were one (1.5%) of the 65 patients with leukaemia/lymphoma (HTLV-I), 6 of 40 (15.0%) individuals (HTLV-I = 1 , HTLV-II = 3, HTLV-I/II = 2) with sexually transmitted diseases (STD), one of 25(4.0%) subjects with genital candidiasis for HTLV-I and 2 of 60 (33.3%) healthy individuals (one for HTLV-I and one for HTLV-I/II). There was a significant difference (P < 0.025) between the prevalence of HTLV-I/II infections among patients with lymphoma/leukaemia and those who attended STD clinic in Ibadan, Nigeria. This study also suggests that while HTLV-I and HTLV-II may be important sexually transmitted viruses, they may not be specific aetiological agents of the common lymphoproliferative disorders in Nigeria.

Adult↗

PubMed1996

Isolation and characterization of a new subtype A variant of human immunodeficiency virus type I from Nigeria.

We have isolated a new variant of HIV-1 from Nigeria, Africa. The virus was recovered from the peripheral blood mononuclear cells (PBMCs) of an apparently healthy 23-year-old male from Ibadan, Nigeria. The in vitro studies indicated that the virus was highly cytopathic and replicated well in normal PBMCs, established T-cell lines and the monocytic cell line U937. The highest replicative titre of the virus was obtained in freshly isolated primary macrophage/monocyte cells which also showed the least cytopathology. Most other cultures showed single-cell cytolysis and giant cells, and syncytia were not induced in the HTLV-1 infected MT-2 cells. Since no HIV strain has been isolated from Nigeria, we obtained cDNA clones containing the env gene, to further characterize the Nigerian virus. Based on the DNA sequence analysis of 14 clones containing the coding region for its gp 120 protein, the Nigerian HIV isolate has been classified as HIV-1 subtype A. Only one subtype A virus from Rwanda has been characterized and this virus has not been shown to exhibit extreme cytopathicity in various cell types as was observed with the Nigerian strain. Further, the ability of this virus to grow well in lymphocytes, monocytes and macrophages and to exhibit cytopathicity without causing syncytia are uncommon properties distinguishing the Nigerian virus from other HIV-1 strains. Since most macrophage-tropic viruses have been associated with 'neurotropism', the isolation of an HIV-1 strain from the blood of an individual with no known neurological disorder indicates that this rapidly replicating cytopathic virus, with a broad host range, may play an important role in the pathogenesis of HIV disease. This represents the first report of an HIV-1 isolate from Nigeria.

Adult↗

PubMed1996

Multiple organ injuries and failures caused by shock and reperfusion after gunshot wounds.

Experiments were performed to observe the changes of multiple system organ failure (MSOF) and gut barrier function caused by shock and reperfusion after gunshot wounds. Eighteen dogs were divided randomly into two groups. In the experimental group, the dogs were subjected to 60 minutes of shock (40mm Hg), followed by reinfusion of shed blood after hindlimb gunshot wounds. In the control group, the dogs experienced pure gunshot wounds without shock and reperfusion. The results showed that dogs in the experimental group developed multiple system organ injuries or failures compared with the control group. The levels of malondialdehyde (MDA) values in plasma were significantly elevated in the experimental group when compared with preinjury and the control group. Gut flora disorder, bacillus intestinalis overgrowth, and bacterial translocation occurred in the experimental group. The pathological results support the gut barrier function injury. The results indicated that pure gunshot wounds do not easily injure gut barrier function and produce MSOF. Gunshot wounds with shock and reperfusion are capable of causing gut flora disorder, bacillus intestinalis overgrowth, and lead to bacterial translocation, furthermore causing MSOF. Although fluid resuscitation is a potential treatment modality, pathogenically, it can lead to MSOF.

Animals↗