Optimizing Recovery After Carpal Tunnel Syndrome Release Surgery: The Role of Counseling in Pain Management and Perioperative Functional Enhancement.

Background: Preoperative patient education is pivotal in improving patient outcomes during the perioperative phase, involving a thorough explanation of what patients can expect. This enhances adherence and reduces perioperative anxiety. In orthopedics, carpal tunnel syndrome, a common and painful hand condition, is effectively managed through surgical release under local anesthesia. Inadequate counseling before such procedures may intensify intraoperative anxiety and increase pain responses. Thus, this research aims to investigate the effects of comprehensive preoperative counseling on various parameters in carpal tunnel release surgery. Methods: A case-control study design was adopted for this study. A retrospective analysis of patients who underwent carpal tunnel release surgery was performed. These patients were categorized into two distinct groups: one group received comprehensive counseling during their clinic visits, while the other group reported receiving less effective counseling. Evaluation encompassed patient-related factors, disease-related aspects, and perioperative variables for both groups. Results: The study comprised 681 participants, with 526 (77.2%) being females, 421 (61.8%) undergoing surgery on the right side, and 519 (76.2%) employed in non-manual occupations. Moreover, 559 (82.1%) were non-smokers, while approximately two-thirds of the cohort had both diabetes and hypertension. The average age of participants was 52 years, and they reported a mean functional disability score of 7.2 out of 10. The comprehensive preoperative counseling group consisted of 333 patients, while the other group included 348 patients. The analysis revealed statistically significant differences between the two groups, including reduced intra-procedural anxiety (p = 0.043), decreased intraoperative pain (p = 0.005), lower rates of wound complications (p = 0.022), and improved self-reported pain relief (p = 0.3). Conclusion: Our study emphasizes the crucial role of preoperative counseling in improving patient experiences during perioperative care, leading to reduced anxiety, milder pain responses, fewer complications, decreased reliance on postoperative pain medication, and increased self-reported pain relief. Level of Evidence: Level III, Case-control retrospective study.

Influence of the rs4238001 Genetic Polymorphism of the SR-B1 Gene on Serum Lipid Levels and Response to Rosuvastatin in Myocardial Infarction Iraqi Patients.

Scavenger receptor type B (SR-BI) is a receptor that binds both native and altered lipoproteins. It was revealed to facilitate utilization of high-density lipoprotein HDL and significantly affect the reverse transport of cholesterol. Therefore, the objectives were to identify the possible role of the genetic variant rs4238001 in patients with myocardial infarction (MI) on serum lipid level, and how this variant could impact the response of rosuvastatin drug. The genotyping of the rs4238001 genetic polymorphism of the SR-B1 gene was performed in 300 participants, including 150 MI patients treated with 20mg/day/4 weeks of rosuvastatin and 150 healthy control using Taq man probes (FAM and VIC) by Real-time PCR technique. The concentrations of the lipid profile were evaluated. The significance of the anthropometric data was revealed in the ejection fraction and smoking status (p < 0.05) between groups. The lipid profile shows either significant differences between control and MI patients (pre-treatment) or between pre-and post-treatment of MI patients (p < 0.05), but not HDL-c (p > 0.05). The minor allele frequency MAF% of the T allele and TT genotype were more frequent in MI patients than in controls (P = 0.173; OR = 3.62; 95% CI = 0.74-17.64). CC genotype was found to be associated with response to rosuvastatin therapy with a change of % (29.08 ± 53.2; p = 0.021). In the Iraqi population, the rs4238001 polymorphism of the SR-B1 gene is associated with variations in serum lipids, and the CC genotype of the SNP is related to higher HDL-C in the lipid-lowering rosuvastatin response.

Assessing changes in range of motion in adolescent patients undergoing myoActivation® for chronic pain related to myofascial dysfunction: a feasibility study.

Introduction: myoActivation® assessment utilizes systemized movement tests to assess for pain and limitations in motion secondary to myofascial dysfunction. myoActivation needling therapy resolves the myofascial components of pain and is associated with immediately observed changes in pain, flexibility, and range of motion. The principal aim of this feasibility study was to objectively characterize the kinematic metrics of upper and lower body motion before and after myoActivation movement tests and therapy. Methods: Five consecutive eligible adolescent participants considered appropriate for myoActivation were consented to receive their myoActivation intervention in a motion laboratory. Clinical motion analysis was used to measure the changes in maximum range of motion (maxROM) and maximum angular speed to maximum ROM (speedROM) of movement tests predicted to change. Metrics were analyzed to assess changes over specified time intervals - i) baseline to after initial myoActivation session, and ii) baseline to after complete myoActivation course. Each participant served as their own control. Results: We demonstrated objective evidence of improved maxROM and/or speedROM in 63% of the movement tests predicted to change after just one session of myoActivation and in 77% of movement tests predicted to change over the complete course of treatment. The myoActivation clinician observed positive change in 11/19 of movement tests across all patients, that were predicted to change after the initial myoActivation session; 81% of these positive changes were confirmed by the kinematic data. Discussion: Clinical motion analysis provides objective support to clinicians evaluating, treating, and teaching myofascial release. A larger, prospective clinical trial is warranted to explore the impact of myoActivation on movement. Refinement of observation techniques and outcome measures established in this feasibility study will strengthen future clinical motion analysis of the myoActivation process.

The etiological effect and genetic risk of +252 A/G variant of TNF-ß gene related to the susceptibility of urinary tract infection in a sample of Iraqi patients with type 2 diabetes: A case control study.

Background and aim: Urinary tract infection (UTI) is the most common infection in type 2 diabetes patients. TNF-ß is a cytokine with multiple functions in immunomodulatory and inflammatory mechanisms. The variation at position +252 A/G of TNF-ß impacts both gene expression and plasma concentration of TNF-ß proteins. The findings may shed light on the genetic factors that predispose diabetic patients in Iraq to UTIs. Methods: A total of 200 individuals were divided into 100 patients with type 2 diabetes, categorized according to UTI, and 100 control subjects. Genetic analysis of +252 A/G of the TNF-ß gene was carried out using the TaqMan probe allele discrimination method. The level of TNF-ß was estimated by the ELISA technique. Results: In the recessive model (GG vs. AA/AG) of TNF-ß + 252 A/G in T2D/UTI patients compared to controls, a significant association p = 0.029 (OR: 2.8; CI 95% = 1.14-7.09): E = 15.6% was observed. Furthermore, in T2D patients without UTI, the dominant model AA versus AG/GG was associated with a preventive role P: 31.3% (OR: 0.4; CI 95% = 0.22-0.88) and a p value = (0.02). Overall, AG proportions showed a high level of TNF-ß within the control group p = 0.03, while all proportions of the +252 A/G showed significant differences in TNF-ß level between groups p ≤ 0.05. Pearson's correlation analysis observed a link between TNF- levels, fasting plasma glucose (FPG), and HbA1c. Conclusion: In T2D patients, the G allele may be linked to a higher probability of UTI, as well as an increased level of TNF-ß in a genotype-dependent manner.

Indoor Built Environment and Older Adults' Activity: A Systematic Review.

Although the physical environment can influence people's activity, there are few knowledge syntheses for indoor environments and older adults' daily life routines. Therefore, we conducted a systematic review of peer-reviewed evidence to inform future research and practice. Inclusion criteria were studies with any research designs, across all years and languages focused on older adults 60 years of age or more, on physical activity/sedentary behaviour and the indoor environment. After searching five databases, two authors completed title/abstract and full-text screening. The last search was on December 19, 2020. We screened 1,367 citations, and included 23 studies situated in private or collective dwellings (e.g., assisted living). We identified physical activity-supportive indoor features across three domains: campus (e.g., amenities, pathways), building (e.g., area, floor level), and fixtures (e.g., elevators, hallways). Knowledge of indoor environmental factors for older adults' engagement in daily activities can guide future research and policy on housing design.

Extended-spectrum Beta-lactamases Encoding Genes among Salmonella Enterica serovar Typhi Isolates in Patients with Typhoid Fever from four Academic Medical Centers Lagos, Nigeria.

BACKGROUND: There is scarce information about the occurrence of extended-spectrum ß-lactamases (ESBLs) in Salmonella enterica serovar Typhi (S. Typhi) from patients with typhoid fever. OBJECTIVE: To study the antimicrobial resistance and ESBL encoding genes among S. Typhi isolates in aforesaid patients from Lagos, Nigeria. METHODS: S. Typhi isolates were collected from blood samples of typhoid fever patients from 4 academic medical centers in Lagos, Nigeria. The identification of isolates and their antibiotic susceptibility testing were performed by standard bacteriological techniques and disc diffusion method, respectively. The production of ESBLs was investigated using combination disk test (CDT) and polymerase chain reaction (PCR). RESULTS: A total of 27 S. Typhi isolates was collected. All isolates were susceptible to imipenem and nitrofurantoin. Fifteen (55.6%) isolates were multidrug-resistant (MDR). The CDT test showed 11 (40.7%) ESBL producer isolates. However, the PCR revealed a higher occurrence rate for ESBL producers (66.7%, n = 18/27). The ESBL genes were as follows: blaCTX-M (37.0%, n = 10/27), blaSHV (18.5%, n = 5/27), and blaTEM (44.4%, n = 12/27). All ESBL positive S. Typhi isolates were MDR. CONCLUSIONS: This study showed the emergence of ESBL-harboring S. Typhi in patients with typhoid fever from Nigeria.

Extended-spectrum Beta-lactamases Encoding Genes among Salmonella Enterica serovar Typhi Isolates in Patients with Typhoid Fever from four Academic Medical Centers in Lagos, Nigeria

ABSTRACT Background: There is scarce information about the occurrence of extended-spectrum β-lactamases (ESBLs) in Salmonella enterica serovar Typhi (S. Typhi) from patients with typhoid fever. Objective: To study the antimicrobial resistance and ESBL encoding genes among S. Typhi isolates in aforesaid patients from Lagos, Nigeria. Methods: S. Typhi isolates were collected from blood samples of typhoid fever patients from 4 academic medical centers in Lagos, Nigeria. The identification of isolates and their antibiotic susceptibility testing were performed by standard bacteriological techniques and disc diffusion method, respectively. The production of ESBLs was investigated using combination disk test (CDT) and polymerase chain reaction (PCR). Results: A total of 27 S. Typhi isolates was collected. All isolates were susceptible to imipenem and nitrofurantoin. Fifteen (55.6%) isolates were multidrug-resistant (MDR). The CDT test showed 11 (40.7%) ESBL producer isolates. However, the PCR revealed a higher occurrence rate for ESBL producers (66.7%, n = 18/27). The ESBL genes were as follows: blaCTX-M (37.0%, n = 10/27), blaSHV (18.5%, n = 5/27), and blaTEM (44.4%, n = 12/27). All ESBL positive S. Typhi isolates were MDR. Conclusions: This study showed the emergence of ESBL-harboring S. Typhi in patients with typhoid fever from Nigeria.

Analysis of anti-apoptotic protein (Bcl-xl) levels and mRNA expression in infertile patients.

In assisted reproductive technology (ART), researchers have tried to predict in vitro fertilization (IVF) outcomes depending on follicular cells apoptosis. Previous reports suggested the B-cell lymphoma-extra-large (BCL-XL) as an apoptosis inhibitor in mammalian ovaries. Therefore, the present research aimed to correlate BCL-XL expression in blood and concentration in follicular fluid (FF) with some outcomes of IVF. A prospective case-control study on infertile women (n=80, mean age= 31.18± 6.04 years) who underwent an IVF program at Kamal Al-Samarai Hospital (Baghdad/Iraq), July 2021- January 2022. All women were split based on pregnancy outcome into two groups: the non-pregnant group (n=40) and the pregnant group (n=40). Samples of FF and blood were assembled at oocyte retrieval time. The BCL-XL mRNA expression was assessed with the Real-Time Quantitative Reverse Transcription-polymerase chain reaction (Real-Time qRT-PCR) technique, whereas the BCL-XL concentration in FF was investigated by sandwich enzyme-linked immunosorbent assay (ELISA). The BCL-XL concentration in FF from pregnant group (3.90 ng/ml ±1.16) raised significantly (P = 0.00) compared with non-pregnant group (1.90 ng/ml ± 0.63). Similarly, the BCL-XL mRNA expression in blood from pregnant group (0.73 ±0.31) raised significantly (P = 0.00) compared with non-pregnant group (0.34± 0.12). In addition, FF BCL-XL concentration associated significantly with fertilization rate (r= 0.399, P=0.048). The research proposed that the elevation of anti-apoptotic BCL-XL might assist in diminished apoptosis in pregnant women who underwent IVF treatment.

Polyethylene Glycol Functionalized Graphene Oxide Nanoparticles Loaded with Nigella sativa Extract: A Smart Antibacterial Therapeutic Drug Delivery System.

Flaky graphene oxide (GO) nanoparticles (NPs) were synthesized using Hummer's method and then capped with polyethylene glycol (PEG) by an esterification reaction, then loaded with Nigella sativa (N. sativa) seed extract. Aiming to investigate their potential use as a smart drug delivery system against Staphylococcus aureus and Escherichia coli, the spectral and structural characteristics of GO-PEG NPs were comprehensively analyzed by XRD, AFM, TEM, FTIR, and UV- Vis. XRD patterns revealed that GO-PEG had different crystalline structures and defects, as well as a higher interlayer spacing. AFM results showed GONPs with the main grain size of 24.41 nm, while GONPs-PEG revealed graphene oxide aggregation with the main grain size of 287.04 nm after loading N. sativa seed extract, which was verified by TEM examination. A strong OH bond appeared in FTIR spectra. Furthermore, UV- Vis absorbance peaks at (275, 284, 324, and 327) nm seemed to be correlated with GONPs, GO-PEG, N. sativa seed extract, and GO -PEG- N. sativa extract. The drug delivery system was observed to destroy the bacteria by permeating the bacterial nucleic acid and cytoplasmic membrane, resulting in the loss of cell wall integrity, nucleic acid damage, and increased cell-wall permeability.

Malaria serology data from the Guiana shield: first insight in IgG antibody responses to Plasmodium falciparum, Plasmodium vivax and Plasmodium malariae antigens in Suriname.

BACKGROUND: Suriname has accomplished a steep decline in malaria burden, even reaching elimination levels. Plasmodium serology data are not available for Suriname and even extremely scarce within the region, therefore malaria serology testing was introduced, country customized cut-off values were determined and a study was performed to explore the antibody status for Plasmodium falciparum, Plasmodium vivax and Plasmodium malariae. METHODS: A cross-sectional survey was conducted between July 2017 and March 2018 in two areas of the interior with different malaria settings: Stoelmanseiland, representing Maroon villages and Benzdorp, a gold mining area, with mostly Brazilian miners. Dried blood spots (DBS) were collected (n = 197) and antibody presence against seven Plasmodium antigens was detected using a multiplex bead-based, IgG antibody assay. Demographic information was gathered through a questionnaire. Country customized cut-off values were generated from a Surinamese malaria-naïve reference population (n = 50). RESULTS: Serological analysis for the reference population revealed cut-off values ranging from 14 MFI for LSA-1 to 177 MFI for PmMSP-119. Seroprevalence against any of the three MSP-119 antibodies was similar in both regions and surpassed 75%. Single seropositivity against PfMSP-119 antibodies was higher in Stoelmanseiland (27.0%) than Benzdorp (9.3%), in line with the historical malaria burden of Stoelmanseiland, while the reverse was observed for PvMSP-119 antibodies. Despite sporadic reports of P. malariae infections, PmMSP-119 antibody presence was 39.6%. A more detailed examination of P. falciparum serology data displayed a higher seroprevalence in villagers (90.7%) than in Brazilians (64.6%) and a highly diverse antigenic response with 22 distinct antibody combinations. CONCLUSIONS: The results on the malaria antibody signature of Maroon villagers and Brazilian miners living in Suriname displayed a high Plasmodium seroprevalence, especially for P. falciparum in villagers, still reflecting the historical malaria burden. The seroprevalence data for both regions and the observed combinations of P. falciparum antibodies provided a valuable dataset from a historically important region to the international malaria serology knowledge. First insight in malaria serology data for Suriname indicated that the use of other target groups and assessment of age-dependent seroprevalence are required to successfully use malaria serology as tool in the national elimination strategy.

Risk Factors for Parainfluenza Virus Lower Respiratory Tract Disease after Hematopoietic Cell Transplantation.

Parainfluenza virus (PIV) infection can progress from upper respiratory tract infection (URTI) to lower respiratory tract disease (LRTD) in immunocompromised hosts. Risk factors for progression to LRTD and presentation with LRTD without prior URTI are poorly defined. Hematopoietic cell transplant (HCT) recipients with PIV infection were retrospectively analyzed using standardized definitions of LRTD. PIV was detected in 540 HCT recipients; 343 had URTI alone and 197 (36%) had LRTD (possible, 76; probable, 19; proven, 102). Among 476 patients with positive nasopharyngeal samples, the cumulative incidence of progression to probable/proven LRTD by day 40 was 12%, with a median time to progression of 7 days (range, 2 to 40). In multivariable analysis monocytopenia (hazard ratio, 2.22; P = .011), steroid use ≥1mg/kg prior to diagnosis (hazard ratio, 1.89; P = .018), co-pathogen detection in blood (hazard ratio, 3.21; P = .027), and PIV type 3 (hazard ratio, 3.57; P = .032) were associated with increased progression risk. In the absence of all 4 risk factors no patients progressed to LRTD, whereas progression risk increased to >30% if 3 or more risk factors were present. Viral load or ribavirin use appeared to have no effect on progression. Among 121 patients with probable/proven LRTD, 64 (53%) presented LRTD without prior URTI, and decreased lung function before infection and lower respiratory co-pathogens were risk factors for this presentation. Mortality was unaffected by the absence of prior URTI. We conclude that the risk of progression to probable/proven LRTD exceeded 30% with ≥3 risk factors. To detect all cases of LRTD, virologic testing of lower respiratory samples is required regardless of URTI symptoms.

Rapidly progressive Kaposi's Sarcoma in an Iraqi boy received Valproic acid: a case report and review of literature.

BACKGROUND: Kaposi's sarcoma (KS), an endothelial neoplasm, is associated with human herpes virus (HHV) -8 infection. KS has four clinical sub-types: Mediterranean/classic, African/endemic, human immunodeficiency virus (HIV) -associated/epidemic, and transplantation-related/iatrogenic. Immunosuppression is an important cofactor in KS process. Classic KS (CKS) is exceedingly rare in children and when occurs, it is much more disseminated than adults. The epidemic, HIV-associated and the iatrogenic forms of childhood KS are a result of a profound and acquired T-cell deficiency. To our knowledge, this is the first paediatric KS case report from Iraq. Our patient was showing an unusual aggressive course of the disease while receiving Valproic acid (VPA) of the potential immune-suppressive effect. CASE PRESENTATION: A six-year-old Iraqi boy, who had cerebral palsy (CP) and epilepsy since the age of 9-months, had received VPA to control his seizures. He developed skin discoloration followed by nodules that disseminated proximally from the lower extremities to the groin, face, ears and oral cavity, and then he died from severe respiratory distress after 110 days from the disease evolution. KS diagnosis was proved by a skin biopsy. As the patient was of Arab-Asian ethnicity and was HIV-seronegative status, accordingly, his condition best fitted the classic form of KS. However, recent studies showed the link of VPA with the reactivation of HHV-8. Moreover, accumulated experimental and clinical data elucidated that VPA induces T-cell suppression. Given that there was a lack of facilities to perform the laboratory immunological diagnostic tests in Iraq, the VPA-induced effect on immunity in our case (iatrogenic KS) could not be evaluated. CONCLUSIONS: Our report demonstrates a rare, rapidly progressing paediatric KS case and highlights the possible role of the 5-years' administration of VPA and its challenging effect on cellular immunity based on recent studies. Thus, VPA could have promoted the development of the KS in our patient. This report also recalls the need of paediatricians to consider KS especially when the skin lesion appears at the child's foot even in countries outside the geographical map of the disease.

First Chikungunya Outbreak in Suriname; Clinical and Epidemiological Features.

BACKGROUND: In June 2014, Suriname faced the first Chikungunya outbreak. Since international reports mostly focus on hospitalized patients, the least affected group, a study was conducted to describe clinical characteristics of mainly outpatients including children. In addition, the cumulative incidence of this first epidemic was investigated. METHODOLOGY: During August and September 2014, clinically suspected Chikungunya cases were included in a prospective follow-up study. Blood specimens were collected and tested for viral RNA presence. Detailed clinical information was gathered through multiple telephone surveys until day 180. In addition, a three stage household-based cluster with a cross-sectional design was conducted in October, December 2014 and March 2015 to assess the cumulative incidence. PRINCIPAL FINDINGS: Sixty-eight percent of symptomatic patients tested positive for Chikungunya virus (CHIKV). Arthralgia and pain in the fingers were distinctive for viremic CHIKV infected patients. Viremic CHIKV infected children (≤12 years) characteristically displayed headache and vomiting, while arthralgia was less common at onset. The disease was cleared within seven days by 20% of the patients, while 22% of the viremic CHIKV infected patients, mostly women and elderly reported persistent arthralgia at day 180. The extrapolated cumulative CHIKV incidence in Paramaribo was 249 cases per 1000 persons, based on CHIKV self-reported cases in 53.1% of the households and 90.4% IgG detected in a subset of self-reported CHIKV+ persons. CHIKV peaked in the dry season and a drastic decrease in CHIKV patients coincided with a governmental campaign to reduce mosquito breeding sites. CONCLUSIONS/SIGNIFICANCE: This study revealed that persistent arthralgia was a concern, but occurred less frequently in an outpatient setting. The data support a less severe pathological outcome for Caribbean CHIKV infections. This study augments incidence data available for first outbreaks in the region and showed that actions undertaken at the national level to mount responses may have positively impacted containment of this CHIKV outbreak.

First Chikungunya outbreak in Suriname: Clinical and epidemiological features

Background In June 2014, Suriname faced the first Chikungunya outbreak. Since international reports mostly focus on hospitalized patients, the least affected group, a study was conducted to describe clinical characteristics of mainly outpatients including children. In addition, the cumulative incidence of this first epidemic was investigated. Methodology During August and September 2014, clinically suspected Chikungunya cases were included in a prospective follow-up study. Blood specimens were collected and tested for viral RNA presence. Detailed clinical information was gathered through multiple telephone surveys until day 180. In addition, a three stage household-based cluster with a cross-sectional design was conducted in October, December 2014 and March 2015 to assess the cumulative incidence. Principal Findings Sixty-eight percent of symptomatic patients tested positive for Chikungunya virus (CHIKV). Arthralgia and pain in the fingers were distinctive for viremic CHIKV infected patients. Viremic CHIKV infected children (≤12years) characteristically displayed headache and vomiting, while arthralgia was less common at onset. The disease was cleared within seven days by 20% of the patients, while 22% of the viremic CHIKV infected patients, mostly women and elderly reported persistent arthralgia at day 180. The extrapolated cumulative CHIKV incidence in Paramaribo was 249 cases per 1000 persons, based on CHIKV self-reported cases in 53.1% of the households and 90.4% IgG detected in a subset of self-reported CHIKV+ persons. CHIKV peaked in the dry season and a drastic decrease in CHIKV patients coincided with a governmental campaign to reduce mosquito breeding sites. Conclusions/Significance This study revealed that persistent arthralgia was a concern, but occurred less frequently in an outpatient setting. The data support a less severe pathological outcome for Caribbean CHIKV infections. This study augments incidence data available for first outbreaks in the region and showed that actions undertaken at the national level to mount responses may have positively impacted containment of this CHIKV outbreak.

Terahertz emission in ladder plus Y-configurations in double quantum dot structure.

The ladder plus Y-double quantum dot (QD) structure has been proposed to improve the second-order nonlinear susceptibility (SONS) under applied electric field. For this purpose, the wetting layer (WL) and QD inhomogeneity contribution in SONS has been considered. In addition, the structure size effect, energy level separation, momentum matrix elements, and pump detuning have been examined, and show that the SONS is increased by using the WL, a low momentum matrix element of WL-QD transition in comparison with interdot transition while QD inhomogeneity reduces SONS to half. This work is predicted to play a key role in terahertz applications, since the frequency emissions obtained are in the range of 75.5-600 µm.

Sensitive and specific time-resolved fluorescence immunoassay of rat C-peptide for measuring hormone secretory and storage capacity of ß-cells in vivo and in vitro.

The limitations of current rat C-peptide assays led us to develop a time-resolved fluorescence immunoassay for measurements in plasma, incubation media, and tissue/cell extracts. The assay uses 2 monoclonal antibodies, binding to different parts of the C-peptide molecule, and allowing, respectively, capture of the peptide and its detection by europium-labeled streptavidin. It is performed on 25-µL samples for a dynamic range from 66pM up to 3900pM C-peptide and displays over 95% recovery of added peptide in the range of 111pM to 2786pM. Its inter- and intra-assay coefficients of variations are, respectively, lower than 7.6% and 4.8%. Cross-reactivities by rat insulin and by human and porcine C-peptide are negligible, and cross-reactivity by mouse C-peptide is 6% ± 2%. The assay has been validated for in vivo and in vitro measurements of C-peptide release and cellular content. Release patterns were similar to those for insulin and occurred in equimolar concentrations for both peptides. The molar C-peptide contents in purified ß-cells and isolated islets were similar to the corresponding insulin contents. This was also the case for pancreatic extracts containing protease inhibitors.

Discriminant value of serum HBV DNA levels as predictors of liver fibrosis in chronic hepatitis B.

Current guidelines recommend antiviral therapy in chronic hepatitis B (HBV) patients with significant histological disease. We aimed to compare histological fibrosis (METAVIR, ≥F2) in patients with HBV DNA ≥20,000 IU/mL vs. ≥2000 IU/mL and identify predictors of fibrosis. We performed prospective liver biopsies on 203 HBeAg-negative patients in four groups: Group I (n = 55): HBV DNA ≥20,000 IU/mL and persistently elevated alanine aminotransferase (ALT) levels (PEALT; >40 U/L); Group II (n = 34): HBV DNA ≥20,000 IU/mL and persistently normal ALT (PNALT); Group III (n = 40): HBV DNA <20,000 IU/mL and PEALT; and Group IV (n = 74): HBV DNA <20,000 IU/mL, and PNALT. We reanalysed all groups in relation to updated cut-off for treatable viremia (2000 IU/mL). Genotype D was detected in 86% of patients. Hepatic fibrosis ≥F2 was detected in 72.7%, 52.9%, 57.5% and 18.9% in Groups I-IV, respectively (P < 0.0001). Except in Group II with a trend for lower ≥F2 fibrosis (P = 0.067), there was no significant difference by using HBV DNA cut-off 20,000 vs. 2000 IU/mL. Multivariate logistic regression analysis identified study Group IV (OR, 0.0276; CI: 0.088-0.868; P = 0.0276) and milder (A0-1) necroinflammatory grade (OR, 0.135; CI: 0.063-0.287; P < 0.0001) as independent predictors of ≥F2 fibrosis. The specificity, positive and negative predictive values for PEALT in detection of ≥F2 fibrosis for viremia ≥2000 IU/mL (80%, 69% and 65%, respectively) or ≥20,000 IU/mL (86%, 73% and 63%, respectively) were similar, with a marginal gain in sensitivity (51% vs. 42%, respectively). Significant fibrosis is prevalent in a large proportion of HBeAg-negative patients with high viremia and persistently normal ALT. Lower HBV DNA cut-offs could be adopted with marginal gains in fibrosis detection and without loss of diagnostic accuracy.

Development of a multipurpose time-resolved fluorescence immunoassay for rat insulin.

We present a time-resolved fluorescence immunoassay (TR-FIA) for the measurement of rat insulin in cell extracts and culture media. This assay is based on the binding of two monoclonal antibodies to different parts of the insulin molecule in a 96-well microtiter plate. For the detection, europium-labeled streptavidin that interacts with the second biotinylated antibody is used. Samples of 25 microl could be analyzed in less than 2 days with a measuring range between 5 and 1250 pg (0.2-50 microg/L or 34.4-8600 pM). The inter- and intraassay percentage coefficients of variation were less than 8.3 and 5.1, respectively. Recoveries of 0.48 to 40 microg/L rat insulin, added to culture medium, ranged between 94 and 107%. Results were significantly correlated with those of an in-house radioimmunoassay (RIA) for rodent insulin (P<0.0001, r(2)=0.99). The TR-FIA method had a similar detection limit (0.16 microg/L), but its working range was at least 5-fold larger. Additional advantages include the lower cost, the applicability to measurements in tissue and serum, and the quantification of insulin from other species.

Simultaneous measurement of plasma concentrations of proinsulin and C-peptide and their ratio with a trefoil-type time-resolved fluorescence immunoassay.

BACKGROUND: When the concentrations of 2 or more substances are measured separately, their molar ratios are subject to the additive imprecisions of the different assays. We hypothesized that the cumulative error for concentration ratios of peptides containing a common sequence might be minimized by measuring the peptides simultaneously with a "trefoil-type" immunoassay. METHODS: As a model of this approach, we developed a dual-label time-resolved fluorescence immunoassay (TRFIA) to simultaneously measure proinsulin, C-peptide, and the proinsulin-C-peptide ratio (PI/C). A monoclonal antibody captures all C-peptide-containing molecules, and 2 differently labeled antibodies distinguish between proinsulin-like molecules and true C-peptide. RESULTS: The trefoil-type TRFIA was capable of measuring plasma C-peptide and proinsulin simultaneously without mutual interference at limits of quantification of 48 and 8125 pmol/L, and 2.1 and 197 pmol/L, respectively. Within-laboratory imprecision values for the trefoil-type TRFIA ranged between 8.4% and 12% for the hormone concentrations. Unlike the hormone results obtained with separate assays, imprecision did not increase when PI/C was calculated from trefoil assay results (P < 0.05). Peptide concentrations were highly correlated with results obtained in individual comparison assays (r(2) > or = 0.965; P < 0.0001). The total error for PI/C obtained with the trefoil-type TRFIA remained < or = 25% over a broader C-peptide range than with separate hormone assays (79-7200 pmol/L vs 590-4300 pmol/L C-peptide). Preliminary data indicate little or no interference by heterophile antibodies. CONCLUSIONS: The developed trefoil-type TRFIA is a reliable method for simultaneous measurement of proinsulin, C-peptide, and PI/C and provides proof of principle for the development of other trefoil-type multiple-label immunoassays.

Permeability through DOPC/dodecane membranes: measurement and LFER modelling.

The permeabilities of 43 ionisable compounds through membranes consisting of 2% dioleylphosphatidylcholine (DOPC) in dodecane at pH values between 3 and 10 have been measured. The observed values are corrected for the effects of ionisation and diffusion through the unstirred water layer in order to obtain estimates of intrinsic permeability. The intrinsic permeabilities are modelled using Abraham's linear free energy relation method. This not only provides a predictive model of membrane permeability, but also reveals the factors determining passive permeation through membranes made from 2% DOPC in dodecane. Hydrogen bonding dominates, acting to strongly inhibit permeation, polarity/polarisability effects are less important, and size acts to enhance permeation.