Ratio Of Hb Research Articles

Surveillance of mosquitoes harnessing their buzzing sound

Mosquito surveillance for vector-borne disease management relies on traditional morphological and molecular techniques, which are tedious, time-consuming, and costly. The present study describes a simple and efficient recording device that analyzes mosquito sound to estimate species composition, male-female ratio, fed-unfed status, and harmonic convergence interaction using fundamental frequency (F0) bandwidth, harmonics, amplitude, and combinations of these parameters. The study examined a total of 19 mosquito species, including 3 species of Aedes, 7 species of Anopheles, 1 species of Armigeres, 5 species of Culex, 1 species of Hulecoetomyia, and 2 species of Mansonia. Among them, the F0 ranges between 269.09 ± 2.96 Hz (Anopheles culiciformis) to 567.51 ± 3.82 Hz (Aedes vittatus) and the harmonic band (hb) number ranges from 5 (An. culiciformis) to 12 (Ae. albopictus). In terms of species identification, the success rate was 95.32 % with F0, 84.79 % with F0-bandwidth, 84.79 % with harmonic band (hb) diversity, and 49.7 % with amplitude (dB). The species identification rate has gone up to 96.50 % and 97.66 % with the ratio and multiplication of F0 and hb, respectively. This is because of the matrices that combine multiple sound attributes. Comparatively, combinations of the amplitude of the F0 and the higher harmonic frequency band were non-significant for species identification (60.82 %). The fed females have shown a considerable increase in F0 in comparison to the unfed. The males of all the species possessed significantly higher frequencies with respect to the females. Interestingly, the presence of male-female of Ae. vittatus together showed harmonic convergence between the 2nd and 3rd harmonic bands. In conclusion, the sound-based technology is simple, precise, and cost-effective and provides better resolution for species, sex, and fed-unfed status detection in comparison to conventional methods. Real-time surveillance of mosquitoes could potentially utilize this technology.

Individual and combined associations of alanine aminotransferase and hemoglobin with metabolic syndrome in the elderly in Qingdao, China.

Combined associations of alanine aminotransferase (ALT) and hemoglobin (Hb) with metabolic syndrome (MetS) have not been assessed yet. The current study investigated the independent and combined relationships between ALT, Hb, and MetS in the elderly. The 37,966 elderly participants aged 65 years and older were recruited from community centers in Qingdao, China. The sampled elderly population visited the health centers once a year where they were offered a free health checkup. Based on a combination of ALT and Hb levels categorized by tertile, participants were grouped into nine groups (Group 1-9). Logistic regression models were used to analyze the individual and combined associations of ALT and Hb with MetS. ALT and Hb were both independently related to MetS in both genders. With the elevation of ALT or Hb levels, risks for MetS and its components increased. Compared to the reference group (the 1st tertiles of both ALT and Hb levels), respective odds ratio of combined ALT and Hb for MetS in Group 2-9 ranged from 1.32-3.38 and 1.14-2.31 in men and women after adjusting for age, sex, education, married status, current smoking, current drinking, physical activity, and diet habit. ALT and Hb were both independently related to MetS and its components. Combined ALT and Hb levels could increase risks of MetS and its components than an elevation in ALT or Hb alone.

Hematological Change in Type II Diabetic Mellitus (TIIDM) patient Infected with intestinal parasites in Kirkuk/Iraq

Abstract: Type II Diabetic Mellitus (TIIDM) is a group of metabolic syndrome described by decline sensitivity of target organs to insulin and confirm or relative insufficiency of insulin excretion followed by electrolytes, water, protein, fat and other metabolic disorders, these defect result in diabetic patient to be susceptible to infect with intestinal parasites. The current study is conducted on 106 Iraqi participants,(67 with TIIDM patients and infected with parasite and 39 TIIDM without parasitic infection as control),aged (25 – 75) years, whom diagnosed by Consultant physician, according to the clinical signs and laboratory diagnosis HbA1c and hematological test (WBC, NEU, LYM, Hb ), during the period between November 2021 to March 2022. The practical part conducted at Kirkuk city in laboratories of Azadi Teaching Hospital (ATH). Two ml of blood sample were taken by intravenous injection and put in sterile tubes that contain anticoagulant EDTA and performed the following tests: HbA1c, Complete Blood Count (CBC). One hundred and six (106) participates (67 diabetic patients infected with parasite and 39 diabetic patients without parasitic infection (control) after the laboratory6 diagnosis, the result was: the ratio of white blood cell (WBC) and lymphocyte (LYM) increased, but depletion occurred in the ratio of Hb in TIIDM patient infected with parasite. This study proved that Blastocystis hominis is the most common type of parasite that has an effect on type II diabetic patients that affect hematological parameters, and Schistosoma mansoni has the least effect.

Hematological changes in IBS patients with intestinal parasites

Irritable bowel syndrome (IBS) was a chronic functional gastrointestinal disorder with an estimated prevalence of 10% around the globe. (IBS) is a common characterized by recurrent abdominal pain or discomfort associated with altered bowel habit. Humans and animals gut contain intestinal parasites live in, and the intestinal wall is preferred for most of these parasites. Human intestine contaminated by many parasites, the most common of them are intestinal worms, Giardia, blastocyst and others. Method: The current study was conducted on 76 Iraqi participants suffering from Irritable Bowel Syndrome, and the diagnosis is made by the consultant physician, according to clinical signs and laboratory diagnosis (blood test (WBC, NEU, LYM, Hb), during the period from November 2021 to March 2022. Blood The sample (2 ml) was drawn intravenously with a sterile injection and then emptied in a plastic tubes containing EDTA anticoagulant and a complete blood count(CBC) test was performed. A stool sample was taken and examined under a microscope to see if the sample contained parasites or not. Result: We have noticed the presence of different types of parasites in 54 samples with irritable bowel syndrome, the most prominent of them Blastocyst hominis and Entamoeba histolytica and 22 samples that do not contain parasites, after the laboratory diagnosis , the result was that: the ratio of white blood cell (WBC) and lymphocyte (LYM) increased, but decrease occurred in the ratio of Hb for the IBS patient infected with parasite. Conclusion: This study proved that the highest rate of parasite infection was for Blastocystis hominis and the lowest percentage for Teania saginata which also affects the hematological parameters in patients with irritable bowel syndrome.

Nutrition Effect on Iron, TIBC and Albumin Level in Underweight Pregnant Women for Preventing Underweight Baby

According to data from the Indonesian Ministry of Health (2018) stunting is the nutritional problems for children under age of five, where in 2017 about 22.2% children under five experienced stunting. Indonesia is the third country with the highest prevalence stunting in Southeast Asia, where the average in 2005-2017 was 36.4% (WHO). This study focused on providing micronutrient supplements to pregnant women with CED for the prevention of stunting in newborns. Aims to analyze differences in maternal weight, anemia states, albumin levels and albumin levels before and after micronutrient administration. This study used an experimental pre and post test with randomization in the group of pregnant women with CED in Made Surabaya sub-district. Results: Weight comparison (P < 0.001) was significant; Comparison of LILA (P < 0.001) was significant; The ratio of Hb (P < 0.001) was significant; Albumin ratio (P < 0.001) was significant; The ratio of serum iron (P = 0.015) was significant; TIBC comparison (P = 0.004) was significant. In this study, the results of comparative analysis of CED pregnant women were given micronutrient supplementation and without administration, where in the analysis of body weight, LILA, Hb, Albumin, Serum iron and TIBC showed significant differences.

Scalable manufacturing platform for the production of methemoglobin as a non-oxygen carrying control material in studies of cell-free hemoglobin solutions.

Methemoglobin (metHb) arises from the oxidation of ferrous hemoglobin (HbFe2+, Hb) to ferric hemoglobin (HbFe3+, metHb), which is unable to bind gaseous ligands such as oxygen (O2) and carbon monoxide (CO), and binds to nitric oxide (NO) significantly slower compared to Hb. Therefore, metHb does not elicit vasoconstriction and systemic hypertension in vivo due to its extremely slow NO scavenging rate in comparison to cell-free Hb, but will induce oxidative tissue injury, demonstrating the potential of using metHb as a control material when studying the toxicity of cell-free Hb. Hence, the goal of this work was to develop a novel manufacturing strategy for production of metHb that is amenable to scale-up. In this study, small scale (e.g. 1 mL reaction volume) screening experiments were initially conducted to determine the optimal molar ratio of Hb to the oxidization agents hydrogen peroxide (H2O2) or sodium nitrite (NaNO2) to achieve the highest conversion of Hb into metHb. A spectral deconvolution program was employed to determine the molar fraction of various species (hemichrome, metHb, oxyHb, metHb-, and NaNO2) in solution during the oxidation reaction. From this analysis, either a 1:1 or 1:5 molar ratio was identified as optimal molar ratios of Hb:NaNO2 (heme basis) that yielded the highest conversion of Hb into metHb with negligible amounts of side products. Hence in order to reduce the reaction time, a 1:5 molar ratio was chosen for large scale (i.e. 1.5 L reaction volume) synthesis of bovine metHb (metbHb) and human metHb (methHb). The biophysical properties of metHb were then characterized to elucidate the potential of using the synthesized metHb as a non-O2 carrying control material. The haptoglobin binding kinetics of metHb were found to be similar to Hb. Additionally, the synthesized metHb was stable in phosphate buffered saline (PBS, 50 mM, pH 7.4) at 4°C for approximately one week, indicating the high stability of the material.

Expression of MiR-429 in Patients with Acute Lymphoblastic Leukemia and Its Prognostic Value

To analyze the expression level of miR-429 in patients with acute lymphoblastic leukemia(ALL) and its clinical prognostic value. One hundred and Twenty-six patients with ALL treated in our hospital from April 2016 to February 2018 were selected, and 100 healthy persons in the same period were selected as control group. Bone marrow mononuclear cells were collected. The expression level of miR-429 in bone marrow mononuclear cells was detected by RT-PCR, and the correlation of miR-429 expression with clinical characteristics and therapeutic efficacy was analyzed. Kaplan-Meier method and multi-factorial Cox regression model were used to analyze the correlation between the level of microRNA-429 and the prognosis of ALL patients. The relative level of miR-429 in ALL patients was 2.47±0.07, which was signifi-cantly higher than that in control group (P<0.05). The level of miR-429 significantly correlated with the leucocyte level（r=0.994）, LDH（r=0.992）, the ratio of bone marrow primordial cells（r=0.995） and risk grade of ALL patients（r=0.991). The level of miR-429 not correlate with the age, sex, Hb level, Plt level and immunophenotype of ALL patients (P>0.05). The level of miR-429 was not significantly different between CR patients and control group (P>0.05); the level of miR-429 in PR patients was higher than that in control group and CR patients (P<0.05). The level of miR-429 in NR patients was higher than that in other groups (P<0.05). Kaplan-Meier survival analysis showed that the overall survival rate of ALL patients with low expression of miR-429 was better than that of ALL patients with high expression of miR-429 (P<0.05). Univariate Cox regression analysis showed that leukocyte level, ratio of bone marrow primordial cells, Hb and LDH level, risk grading and miR-429 were the factors influencing overall survival rate in ALL patients (P<0.05). Multivariate Cox regression analysis showed that leukocyte level, ratio of bone marrow primordial cells, risk grading, and miR-429 were the factors influencing overall survival rate (P<0.05). The expression of miR-429 is high in ALL patients, which closely relates to the curative effect and pro-gnosis of ALL patients, and can be used as a reference index for evaluation of clinical prognosis of ALL patients.

Clinical role of low hemoglobin ratio in poor neurologic outcomes in infants with traumatic intracranial hemorrhage

Traumatic brain injury (TBI) is the leading cause of pediatric morbidity and mortality worldwide, and half of all fatalities occur in infants aged less than 1 year. We analyzed 129 infants diagnosed with TBI complicated with intracranial hemorrhage confirmed by brain computed tomography. We defined delta hemoglobin (ΔHB) as nadir HB - age specific mean HB, and the ratio of HB (%) as ΔHB/age specific mean HB x 100. Infants with poor neurologic outcomes had a lower admission HB and ΔHB (p < 0.05). The in-hospital mortality rate was 10.1% (13 infants), and the infants who died had a significantly lower ΔHB ratio compared to the survivors. The area under the receiving operating characteristic curve (AUC) of initial Glasgow Coma Score (GCS) in predicting neurologic outcomes was higher than that of ratio of ΔHB (0.881 v.s 0.859). In multivariate logistic regression analysis with the optimal cutoff ratio of ΔHB, it remained an independent predictor for in-hospital mortality and poor neurologic outcomes at discharge and at 6 months. AUC analysis for the ratio of ΔHB for poor neurologic outcomes in infants aged from 0–6 months was 0.85 and the optimal cutoff was −30.7% (sensitivity, 69%; specificity, 92%; positive likelihood ratio (LR+), 8.24; negative likelihood ratio (LR−), 0.34); the AUC was 0.88 in infants aged from 6–12 months and the optimal cutoff was −20.6% (sensitivity, 89%; specificity, 79%; LR+, 4.13; LR−, 0.15).

Metal-Organic Framework Encapsulating Hemoglobin as a High-Stable and Long-Circulating Oxygen Carriers to Treat Hemorrhagic Shock.

As an oxygen-transporting protein, free hemoglobin (Hb) often suffers from the disadvantage of undesirable stability and short blood circulation, which severely impairs the potential clinical applications as the blood substitute. In this work, Hb was facilely encapsulated into a kind of metal-organic frameworks (MOFs) (ZIF-8) inspired by the natural biomineralization process. The obtained ZIF-8 encapsulating Hb (ZIF-8@Hb) showed the small hydrodynamic size of 180.8 nm and neutral zeta potential of -2.1 mV by adjusting the ratio of Hb in ZIF-8 frameworks. Intriguingly, Hb encapsulated by ZIF-8 exhibited significantly enhanced stability in alkaline, oxidation, high temperature, or enzymatic environment compared with free Hb because of the excellent protective MOF coatings. More importantly, the negative charge of Hb neutralized the original positive charge of ZIF-8, which led to the better biocompatibility, lower protein adsorption, and macrophage uptake of ZIF-8@Hb than bare ZIF-8 nanoparticles. Furthermore, ZIF-8@Hb displayed extended blood circulation with the elimination half-life of 13.9 h as well as reduced nonspecific distribution in normal organs compared with free Hb or ZIF-8 nanoparticles. With the above advantages, ZIF-8@Hb showed significantly extended survival time of mice in a disease model of hemorrhagic shock compared with free Hb or bare ZIF-8 nanoparticles. Overall, this work offers a high-stable and long-circulating oxygen carrier platform, which may find wide applications as a blood substitute to treat various oxygen-relevant diseases.

Solid dispersion of berberine hydrochloride and Eudragit® S100: Formulation, physicochemical characterization and cytotoxicity evaluation

The purpose of this study was to develop and evaluate the berberine hydrochloride (HB) - Eudragit S100 solid dispersion to prolong the drug release by exploiting its pH-sensitivity dissolution. Solid dispersion of berberine hydrochloride (HB) with Eudragit® S100 (S100) was prepared by a solvent evaporation method. Based on the evaluating dissolution in vitro, the ratio of HB and S100 was optimized to 1:4. The solid dispersion formation of HB-S100 was characterized by XRD, DSC, and results showed that berberine hydrochloride and Eudragit® S 100 was interacted to form a new complex in amorphous form. In-vitro cytotoxicity studies were evaluated in human colon cancer cells by MTT assay. The 50% inhibitory concentrations of HB for SW480, HCT116 and Caco-2 at 48 h were 43.10, 34.13 and 32.82 μM respectively. When formed dispersion with S100 the 50% inhibitory concentrations for SW480, HCT116 and Caco-2 decreased to 28.16, 22.06 and 15.39 μM. The results indicated that, compared with free HB, HB-S100 demonstrated lower IC50 values. Both HB and HB-S100 induced cells death in a dose- and time-dependent manner.

Change ratio of hemoglobin has predictive value for upper gastrointestinal bleeding.

The present study aimed to identify novel predictors of upper gastrointestinal (GI) bleeding by assessing change ratios of blood test variables. Records of 1,023 patients (431 men and 592 women) who underwent endoscopy between October 2014 and September 2015 at the National Hospital Organization Shimoshizu Hospital (Yotsukaido, Japan) were retrospectively analyzed. Patients whose blood test variables for the time-point of endoscopy and three months previously were available were enrolled and subsequently categorized into a group with and another one without upper GI bleeding (n=32 and 84, respectively), and the respective change ratios were calculated for each group. One-way analysis of variance revealed that in patients with upper GI bleeding, change ratios of white blood cell count and alkaline phosphatase were significantly higher than those in patients without, while change ratios of hemoglobin (Hb), total protein and albumin were significantly reduced. Logistic regression analysis demonstrated that the change ratio of Hb was significantly correlated with upper GI bleeding. Receiver-operator characteristic analysis revealed that an 18.7% reduction of Hb was the threshold value for the prediction of upper GI bleeding. In conclusion, the present study revealed that a ≥18.7% reduction in Hb over three months has predictive value for upper GI bleeding.

Methanotrophic production of polyhydroxybutyrate-co-hydroxyvalerate with high hydroxyvalerate content

Type II methanotrophic bacteria are a promising production platform for PHA biopolymers. These bacteria are known to produce pure poly-3-hydroxybutyrate homopolymer (PHB). We isolated a strain, Methylocystis sp. WRRC1, that was capable of producing a wide range of polyhydroxybutyrate-co-hydroxyvalerate copolymers (PHB-co-HV) when co-fed methane and valerate or n-pentanol. The ratio of HB to HV monomer was directly related to the concentration of valeric acid in the PHA accumulation media. We observed increased incorporation of HV and total polymer under copper-free growth conditions. The PHB-co-HV copolymers produced had decreased melting temperatures and crystallinity compared with methanotroph-produced PHB.

An optimal polymerization process for low mean molecular weight HBOC with lower dimer

The new research tried to improve the distribution of molecular weight of Hb-based oxygen carriers (HBOC), a bottleneck of glutaraldehyde (GDA)-polymerization process. The orthogonal experiments were done on the basis of the early study of human placenta Hemoglobin (Hb)-crosslinked-GDA and three factors were selected including the molar ratio of GDA and Hb, Hb concentration, and the rate of the feeding GDA. The optimal match condition of polymerization process prepared for the purpose of lower mean molecular weight, content of super-weight molecule, and the content of dimer. The results showed that the molar ratio of GDA and Hb was the greatest influencing factor on the molecular weight distribution of polymerized-Hb, followed by the Hb concentration, and the last is the rate of feeding GDA. The optimum matching conditions had reached the objective that the mean molecular weight with 155.54 ± 5.79, the content of dimer with 17.23 ± 3.71, and content of super-weight molecule with 0.17 ± 0.09, and the results can be repeated in the 30 times expansion experiments.

Solid state synthesis, crystal growth, atomic packing and physicochemical studies of (E)-2-cyano-3-(3-hydroxyphenyl)acrylamide

The organic crystalline species (E)-2-cyano-3-(3-hydroxyphenyl)acrylamide has been synthesized by solid state reaction between 3-hydroxy benzaldehyde (HB) and 2-cyanoacetamide (CA). The molar ratio of HB and CA forming this new organic entity was found to be 1:1, established with the help of phase diagram study and single crystal XRD analysis. The phase diagram established between HB and CA shows the formation of a new compound surrounded by two eutectics on either side of the compound. Thermal properties such as heat of fusion, entropy of fusion, interfacial energy, and excess thermodynamic functions of the title compound and both eutectics are studied and reported, in addition to a DSC study to analyze the thermal behavior. A large and transparent single crystal with dimensions of 19×7×2mm3 of this newly synthesized compound was grown from the saturated solution of a mixed solvent, employing the slow cooling technique. The single crystal X-ray diffraction analysis showed that the compound crystallizes in the monoclinic system (space group P21/n) with a=9.031(2)Å, b=5.178(2)Å, c=18.330(4)Å, and β=90.86(3)° and comprises dimers of symmetry-related molecules, connected to each other via strong OH···O bonds.

Synthesis of the hemoglobin‐conjugated polymer micelles by click chemistry as the oxygen carriers

Amphiphilic triblock copolymers were synthesized using MPEG, cyclic carbonic ester monomer including propargyl group (MPC) and L‐lactide (LA). These copolymers could self‐assemble into core–shell spherical micelles with propargyl groups on the surface. Azided hemoglobin (Hb) was conjugated with the micelles through click reaction to form Hb‐bearing nano‐micelles. The click reaction conditions, such as the molar ratio of sodium azide to Hb, the binding ratio of Hb to copolymers, the components of catalytic solution, the reaction temperature and time, were thoroughly investigated and optimized. The resulted nano‐micelles had 100 nm diameter with 50–60 wt% of Hb content. The Hb‐based nano‐micelles showed appropriate stability and oxygen carrying capacity, and would have the potential to be used as the new type of artificial oxygen carrier. Copyright © 2011 John Wiley &amp; Sons, Ltd.

Quantitative analysis of hemoglobin content in polymeric nanoparticles as blood substitutes using Fourier transform infrared spectroscopy

Based on the penetrability of IR within the polymeric nanoparticles, a novel Fourier transform infrared spectroscopy (FTIR) method, with polyacrylonitrile (PAN) as the internal reference standard, was developed to quantify the hemoglobin (Hb) content in Hb-based polymeric nanoparticles (HbPN). The HbPN was fabricated by double emulsion method from poly(ethylene glycol)-poly(lactic acid)-poly(ethylene glycol) triblock copolymers. Depending on the characteristic un-overlapped IR absorbances at 1540 cm(-1) of Hb (amide II) and at 2241 cm(-1) of PAN(-C[triple bond]N), calibration equations, presenting the peak height ratio of Hb and PAN as a function of the weight ratio of Hb and PAN, were established. This new quantification method is validated and used to the determination Hb content in HbPN. Due to the good results of this calibration strategy, the proposed simple FTIR approach with minimal sample-needed and solvent-free makes it useful for routine analysis of protein content and could be also applied to any other drug/protein encapsulated particles.

Pathway for Heme Uptake from Human Methemoglobin by the Iron-regulated Surface Determinants System of Staphylococcus aureus

The iron-regulated surface proteins IsdA, IsdB, and IsdC and transporter IsdDEF of Staphylococcus aureus are involved in heme acquisition. To establish an experimental model of heme acquisition by this system, we have investigated hemin transfer between the various couples of human methemoglobin (metHb), IsdA, IsdB, IsdC, and IsdE by spectroscopic and kinetic analyses. The efficiencies of hemin transfer from hemin-containing donors (holo-protein) to different hemin-free acceptors (apo-protein) were examined, and the rates of the transfer reactions were compared with that of indirect loss of hemin from the relevant donor to H64Y/V68F apomyoglobin. The efficiencies, spectral changes, and kinetics of the transfer reactions demonstrate that: 1) metHb directly transfers hemin to apo-IsdB, but not to apo-IsdA, apo-IsdC, and apo-IsdE; 2) holo-IsdB directly transfers hemin to apo-IsdA and apo-IsdC, but not to apo-IsdE; 3) apo-IsdE directly acquires hemin from holo-IsdC, but not from holo-IsdB and holo-IsdA; and 4) IsdB and IsdC enhance hemin transfer from metHb to apo-IsdC and from holo-IsdB to apo-IsdE, respectively. Taken together with our recent finding that holo-IsdA directly transfers its hemin to apo-IsdC, these results provide direct experimental evidence for a model in which IsdB acquires hemin from metHb and transfers it directly or through IsdA to IsdC. Hemin is then relayed to IsdE, the lipoprotein component of the IsdDEF transporter.

Effects of Room Temperature and Body Position Change on Cerebral Blood Volume and Center-of-foot Pressure in Healthy Young Adults

This study aimed to examine the effects of room temperature and body position changes on cerebral blood volume, blood pressure and center-of-foot pressure (COP). Cerebral oxygenation kinetics and blood pressure were measured by near infrared spectroscopy (NIRS) and volume-compensation, respectively, in 9 males and 9 females after rapid standing from sitting and supine positions in low (12 degrees C) or normal (22 degrees C) room temperatures. COP was also measured in a static standing posture for 90 s after rapid standing. The total hemoglobin (Hb) decreased just after standing. Blood pressure after standing at normal temperature tended to decrease immediately but at low temperature tended to decrease slightly and then to increase greatly. The decreasing ratio of total Hb and blood pressure upon standing from a supine position at normal room temperatures was the largest of any condition. Total Hb recovered to a fixed level approximately 25 sec after standing from a sitting position and approximately 35 sec after standing from a supine position. All COP parameters after standing tended to change markedly in the supine position compared to the sitting position, especially at normal temperatures. The COP parameters after standing in any condition were not significantly related to the decreasing ratio of total Hb but were related to the recovery time of total Hb after standing. In conclusion, decreasing ratios of total Hb and blood pressure after standing from a supine position at normal temperatures were large and may affect body sway.

Study on the interaction between CdSe quantum dots and hemoglobin

The interaction between CdSe quantum dots (QDs) and hemoglobin (Hb) was investigated by ultraviolet and visible (UV–vis) absorption spectroscopy, Fourier transform infrared (FTIR) spectroscopy, and fluorescence (FL) spectroscopy. The intensity of UV–vis absorption spectrum of a mixture of CdSe QDs and Hb was obviously changed at the wavelength of 406 nm at pH 7.0, indicating that CdSe QDs could bind with Hb. The influences of some factors on the interactions between CdSe QDs and Hb were studied in detail. The binding molar ratio of CdSe QDs and Hb was 12:1 by a mole-ratio method. The mechanism of the interaction between CdSe QDs and Hb was also discussed.

Hemoglobin conformation couples erythrocyte S -nitrosothiol content to O 2 gradients

It is proposed that the bond between nitric oxide (NO) and the Hb thiol Cys-beta(93) (SNOHb) is favored when hemoglobin (Hb) is in the relaxed (R, oxygenated) conformation, and that deoxygenation to tense (T) state destabilizes the SNOHb bond, allowing transfer of NO from Hb to form other (vasoactive) S-nitrosothiols (SNOs). However, it has not previously been possible to measure SNOHb without extensive Hb preparation, altering its allostery and SNO distribution. Here, we have validated an assay for SNOHb that uses carbon monoxide (CO) and cuprous chloride (CuCl)-saturated Cys. This assay is specific for SNOs and sensitive to 2-5 pmol. Uniquely, it measures the total SNO content of unmodified erythrocytes (RBCs) (SNO(RBC)), preserving Hb allostery. In room air, the ratio of SNO(RBC) to Hb in intact RBCs is stable over time, but there is a logarithmic loss of SNO(RBC) with oxyHb desaturation (slope, 0.043). This decay is accelerated by extraerythrocytic thiol (slope, 0.089; P < 0.001). SNO(RBC) stability is uncoupled from O(2) tension when Hb is locked in the R state by CO pretreatment. Also, SNO(RBC) is increased approximately 20-fold in human septic shock (P = 0.002) and the O(2)-dependent vasoactivity of RBCs is affected profoundly by SNO content in a murine lung bioassay. These data demonstrate that SNO content and O(2) saturation are tightly coupled in intact RBCs and that this coupling is likely to be of pathophysiological significance.