TT Ratio Research Articles

Fetal Thymus Size at 19–22 Weeks of Gestation: A Possible Marker for the Prediction of Low Birth Weight?

Introduction: The purpose was to compare thymus size measured during second trimester screening of fetuses who were subsequently small for gestational age at birth (weight below 10th percentile, SGA group) with fetuses with normal birth weight (control group). We hypothesized that measuring the fetal thymic-thoracic ratio (TT-ratio) might help predict low birth weight. Methods: Using three-vessel view echocardiograms from our archives, we measured the anteroposterior thymus size and the intrathoracic mediastinal diameter to derive TT-ratios in the SGA (n = 105) and control groups (n = 533) between 19+0 and 21+6 weeks of gestation. We analyzed the association between TT-ratio and SGA adjusted to the week of gestation using logistic regression. Finally, we determined the possible TT-ratio cut-off point for discrimination between SGA and control groups by means of receiver operating characteristics (ROC) curve analysis. Results: The TT-ratio was significantly higher in the SGA group than in the control group (p < 0.001). An increase of the TT-ratio by 0.1 was associated with a 3.1-fold increase in the odds of diagnosing SGA. We determined that a possible discrimination cut-off point between SGA and healthy controls was achieved using a TT-ratio of 0.390 (area under the ROC curve 0.695). Conclusion: An increased TT-ratio may represent an additional prenatal screening parameter that improves the prediction of birth weight below the 10th percentile. Prospective studies are now needed to evaluate the use of fetal thymus size as predictive parameter for adverse fetal outcome.

Polymorphisms of CARD9 Gene Predict Disease Progression and Renal Survival of Immunoglobulin A Nephropathy

Introduction: A previous genome-wide association study has identified CARD9 (caspase recruitment domain family member 9) as a susceptibility gene for immunoglobulin A nephropathy (IgAN), which encodes an adapter protein and is related to mucosal immunity. This study aimed to investigate the association of CARD9 variants with the clinicopathological phenotypes and prognosis of IgAN. Methods: Eight single nucleotide polymorphisms within CARD9 were genotyped using Sequenom MassARRAY iPLEX for 986 IgAN patients in this study. Logistic and linear regression analyses adjusted for age and gender were performed to evaluate the effects of CARD9 gene polymorphisms on clinicopathological phenotypes. The Kaplan-Meier method and Cox proportional hazard models were applied to analyze the associations between genetic variants and renal survival. Results: The T allele of rs10747047 was strongly associated with higher levels of serum creatinine (p = 0.005) and lower levels of estimated glomerular filtration rate (p = 0.005). The rs10870149-G and rs10870077-C alleles were associated with elevated 24-h urine protein excretion (p = 0.041 and 0.022, respectively) and more serious segmental glomerulosclerosis lesions (p = 0.005 and 0.041, respectively) in IgAN patients. Carriers with the T allele of rs10781533 and the C allele of rs3812552 also presented with severe segmental glomerulosclerosis lesions (p = 0.001 and 0.010, respectively). Additionally, rs10747047-C and rs10870077-C alleles were independently related to the poor prognosis of IgAN patients after adjustments for covariates (TT vs. CC hazard ratio [HR] = 0.138, 95% confidence interval [95% CI] = 0.022–0.871, p = 0.035; GG vs. CC HR = 0.321, 95% CI = 0.123, 0.836, p = 0.020, respectively). Conclusion: CARD9 variants are associated with disease severity and rapid disease progression for IgAN in a Chinese Han population.

Association between T-182C polymorphism of the norepinephrine transporter SLC6A2(NET) gene and major depressive disorder in Iraqi patients

Major sympathetic nervous system neurotransmitter that is responsible for consciousness, attention, cognitive ability, as well as the function of the majority of body systems, glands, and the immune system, is called Norepinephrine (NE). Norepinephrine transporter (NET) and norepinephrine binding sites are decreased in the brains of MDD patients, showing that dysregulated synaptic NE plays a role in the pathophysiology of MDD. Indeed, different NET polymorphism combinations may be linked to different MDD sub-phenotypes. The aim of the current work is to investigate or detect if there is a relation between T-182C gene polymorphism of SLC6A2 gene with major depressive disorder (MDD) in Iraqi patients.Materials and Methods: Blood specimens were collected from 70 individuals with MDD and 20 healthy individuals as a control group (both patients and control ages ranged between 18-65 years). DNA extracted from white blood cells (WBC), and the T-182C gene was detected and amplified by the PCR-ARMS technique. Results: The distribution of TT, TC, and CC genotype ratio of MDD group was 22.9%, 27.1%, and 50.0%, respectively. While the control group show genotype distribution as 35.0% for TT, 55.0% for TC and 10.0% for CC ratio.

Ultrasonographic evaluation of the fetal thymic-thoracic ratio and its association with conotruncal heart defects

To evaluate the thymic-thoracic ratio (TT ratio) on fetal ultrasound and its association with conotruncal heart defects. A case control study was carried out to retrospectively assess the TT ratio on fetal echocardiograms performed between 19 and 39 weeks of gestation, showing congenital heart defects, from January to December 2018. The control group was comprised of fetuses with no echocardiogram evidence of congenital cardiac malformations. Cases of multiple pregnancies and patients where the TT ratio could not be established have been excluded. A total of 338 pregnancies have been analysed. Fifty-two pregnancies were diagnosed with fetal heart defects (15%), 17 of which showed conotruncal heart defects (32.7%). The TT ratio in normal fetuses (286 pregnancies) increased with gestational age, and had an average of 0.43±0.06. Compared to the control group (normal fetuses), fetuses with conotruncal heart defects had significantly lower mean TT ratio (0.33±0.07). Those that were diagnosed with nonconotruncal heart defects did not show any statistically significant difference in the TT ratios compared with the control group (0.40±0.09vs. 0.43±0.06, respectively). The TT ratio was significantly lower in fetuses with conotruncal heart defects compared with both the control group (normal fetuses) and the fetuses with nonconotruncal heart defects.

Significant difference between coagulation parameters and clinicopathological characteristics in breast cancer.

The purpose of this research is to investigate the correlation between coagulation parameters and survival on patients with breast cancer. A total of 244 patients with breast cancer and 84 patients with metastatic advanced breast cancer admitted to the Second Affiliated Hospital of Chongqing Medical University from January 2017 to February 2019 were selected as the research objects. Their age, tumor size, status of estrogen receptor and progesterone receptor status, status of Her-2 receptor and lymph node were evaluated. Additional 99 cases of benign breast tumors were selected as the control group. All patients were newly diagnosed. PTA, PT ratio, PT, APTT, APTT ratio, TT, TT ratio, PT-INR, FIB, and FDP were detected on all patients. There were significant differences in APTT, APTT ratio, FIB, TT, TT ratio, and FDP between breast cancer and benign tumor control group (P < 0.05). The changes of FIB were correlated with age (P = 0.007), PR status (P = 0.017), and Her-2 status (P = 0.008). The older the age, the higher the FIB level. The FIB level of Er negative state is higher than that of positive state, and the FIB level of PR negative state is also higher than that of positive state. Survival analysis showed that PR negative status, the elevated level of APTT, APTT ratio, TT increased, and TT ratio were the indicators affecting 3-year DFS of patients (P < 0.05). Multivariate COX regression analysis showed that APTT and TT were independent prognostic factors affecting 3 years DFS (P < 0.05). Blood hypercoagulable state in patients with breast cancer, abnormal coagulation system plays an important role in the progress of breast cancer.

Eccentric ankle arthritis in the sagittal plane: a novel description of anterior and posterior ankle arthritis

BackgroundTo report radiographic characteristics of anterior and posterior ankle arthritis, which demonstrates the eccentric narrowing of either aspect of the tibiotalar joint in the sagittal plane. MethodsRadiographic analysis of 19 ankles with anterior arthritis and 16 ankles with posterior arthritis was performed, which were defined as having both (1) eccentric narrowing of the anterior or posterior tibiotalar joint space on lateral radiographs and (2) talar tilt angle less than 4 degrees on anteroposterior radiographs. Measured radiographic parameters were: Talar tilt angle, medial distal tibial angle (MDTA), talar center migration (TCM), anterior distal tibial angle (ADTA), tibial axis-to-talus ratio (TT ratio), talo-first metatarsal (Meary) angle, hindfoot alignment angle (HAA), hindfoot moment arm, and mechanical axis deviation (MAD). An Intergroup comparison analysis, including a normal control group, was also performed. ResultsThe TT ratio was significantly different between each group, indicating a distinct talus position in the sagittal plane. The anterior group had a significantly larger TCM than the control group and lower ADTA compared to other groups, indicating medial translation of the talus and anterior opening of the tibial plafond. The posterior group demonstrated a significantly higher Meary angle and lower HAA compared to other groups and lower MDTA compared to the control group, indicating lower medial longitudinal arch, valgus heel alignment, and varus tibial plafond. The MAD was significantly higher in both the anterior and posterior groups than the control group, indicating varus lower limb alignment. ConclusionAnterior ankle arthritis demonstrated anteromedial translation of the talus and anterior opening of the tibial plafond. Posterior ankle arthritis was associated with the lower medial longitudinal arch and hindfoot valgus, indicating an association with flatfoot deformity. Both anterior and posterior ankle arthritis were associated with varus lower limb alignment.

Hindfoot Alignment after Total Ankle Replacement

Category:Ankle Arthritis; AnkleIntroduction/Purpose:End-stage ankle arthritis can involve misalignment of the ankle in both the coronal and sagittal planes as up to reported 33% to 44% of patients who present for total ankle replacement have greater than 10° of coronal plane deformity. Improvements in both the design and surgical technique for total ankle replacements (TAR) have allowed surgeons to tackle the most challenging of multiplanar ankle deformities. Normalization of the sagittal and coronal alignment is key in improving survivorship and functional outcomes in TAR. In the present study, we analyzed how both the ankle and hindfoot alignment for both a fixed-bearing and mobile bearing TAR system changes over time. Specifically, we measured coronal and sagittal alignment of both the ankle and hindfoot complex. We hypothesize that both significant differences would be seen between all time points and pre-operative radiographs, and that these differences would not change over time.Methods:A retrospective study performed by a single orthopaedic surgeon was performed on two independent groups of patients undergoing two different systems for total ankle replacement: Zimmer TAR (lateral-approach, fixed-bearing, n=89) and Hintegra (anterior approach, mobile-bearing, n=81). We noted specific demographic data and radiographic data were measured including: Hindfoot alignment view angle (HAV), Hindfoot alignment distance (HAVD), tibiotalar ratio, α angle and β angle. These were measured pre-operatively, and 6 months, 12 months, and 24 months post-operatively. Within-group comparisons were performed using one-way repeated-measures ANOVA (1-w rANOVA), analyzing temporal course of clinical data (comparisons between different time points, e.g. T0vsT6vsT12vsT24) within the Hintegra and Zimmer groups. To compare the time course of clinical measures between the two groups, 2-w rANOVAs were performed for SA, SD, TT ratio, α and β angle. Specifically, time*group interaction was tested.Results:At the ankle joint itself, as measured by the α and β angles (p>.05), the position of the components remains relatively similar in both the fixed and mobile bearing TAR over the course of 24 months. The sagittal alignment, as measured by the TT ratio, demonstrated a posterior shifting of the talus in the mobile bearing group (p=.036). Though the fixed and mobile- bearing TAR had both significant hindfoot alignment improvement between the pre-op radiographs and twenty-four months, over time, the fixed-bearing ankle had a significant increase in both the HAV and HAVD (p<.001), suggesting a dynamism of the hindfoot in the fixed-bearing ankle.Conclusion:Correcting coronal and sagittal alignment is important for the long-term survivorship of a TAR. The fixed and mobile-bearing implants had maintained coronal and sagittal alignment in the short term, the temporal course of the fixed-bearing ankle showed an increased in the valgus positioning of the hindfoot.

Influence of maternal HIV infection on fetal thymus size.

Objective To reveal the effect of a maternal human immunodeficiency virus (HIV) infection on the fetal thymus size. Methods The sonographic fetal thymus size was measured retrospectively in 105 pregnancies with maternal HIV infection and in 615 uncomplicated singleton pregnancies. The anteroposterior thymic and the intrathoracic mediastinal diameter were determined in the three-vessel view and their quotient, the thymic-thoracic ratio (TT ratio), was calculated. The study group was subdivided into three groups by the maternal viral load on the date of ultrasound (<50 cop./mL, 50-1000 cop./mL, >1000 cop./mL). Furthermore, an association between prognostic factors of the HIV infection such as the lymphocyte count, CD4/CD8 ratio, HIV medication and the thymus size, was investigated using correlation analyses. Results Fetal thymus size in pregnancies of HIV-positive mothers showed to be noticeably larger than in uncomplicated pregnancies. The mean TT ratio in the HIV-positive group was 0.389 and in the control group 0.345 (P < 0.001). There was no association between any maternal HIV parameter or medication and the size of the thymus gland. Conclusion Maternal HIV infection was associated with an increased fetal thymus size. Further consequences of intrauterine HIV exposure for fetal outcome and the development of the immune system of HIV-exposed uninfected (HEU) infants must be discussed.

Hindfoot Alignment after Total Ankle Replacement

Category:Ankle, Ankle ArthritisIntroduction/Purpose:End-stage ankle arthritis can involve misalignment of the ankle in both the coronal and sagittal planes as up to reported 33% to 44% of patients who present for total ankle replacement have greater than 10° of coronal plane deformity. Normalization of the sagittal and coronal alignment is key in improving survivorship and functional outcomes in TAR. In the present study, we analyzed how both the ankle and hindfoot alignment for both a fixed-bearing and mobile bearing TAR system changes over time. Specifically, we measured coronal and sagittal alignment of both the ankle and hindfoot complex. We hypothesize that both significant differences would be seen between all time points and pre-operative radiographs, and that these differences would not change over time.Methods:A retrospective study performed by a single orthopaedic surgeon was performed on two independent groups of patients undergoing two different systems for total ankle replacement: Zimmer TAR (lateral-approach, fixed-bearing, n=89) and Hintegra (anterior approach, mobile-bearing, n=81). We noted specific demographic data and radiographic data were measured including: Hindfoot alignment view angle (HAV), Hindfoot alignment distance (HAVD), tibiotalar ratio, a angle and ß angle. These were measured pre-operatively, and 6 months, 12 months, and 24 months post-operatively. Within-group comparisons were performed using one-way repeated-measures ANOVA (1-w rANOVA), analyzing temporal course of clinical data (comparisons between different time points, e.g. T0vsT6vsT12vsT24) within the Hintegra and Zimmer groups. To compare the time course of clinical measures between the two groups, 2-w rANOVAs were performed for SA, SD, TT ratio, a and ß angle. Specifically, time*group interaction was tested.Results:At the ankle joint itself, as measured by the a and ß angles (p>.05), the position of the components remains relatively similar in both the fixed and mobile bearing TAR over the course of 24 months. The sagittal alignment, as measured by the TT ratio, demonstrated a posterior shifting of the talus in the mobile bearing group (p=.036). Though the fixed and mobile-bearing TARhad both significant hindfoot alignment improvement between the pre-op radiographs and twenty-four months, over time, the fixed-bearing ankle had a significant increase in both the HAV and HAVD (p<.001), suggesting a dynamism of the hindfoot in the fixed-bearing ankle.Conclusion:Correcting coronal and sagittal alignment is important for the long-term survivorship of a TAR. The fixed and mobile-bearing implants had maintained coronal and sagittal alignment in the short term, the temporal course of the fixed-bearing ankle showed an increased in the valgus positioning of the hindfoot. The mobile-bearing implant maintained its hindfoot alignment over the course of the study. More studies are needed to explore the clinical implications of this new data.

Organic geochemical insights from oil seeps, tars, rocks, and mud volcanoes on the petroleum systems of the Sinú-San Jacinto basin, Northwestern, Colombia

Despite the abundance of oil and gas seeps, the Sinú-San Jacinto (SSJ) is an under-explored and poorly understood basin, especially on the dynamics of its petroleum system(s). Recent studies of source rock extracts and oil seeps show that in the Cenozoic sedimentary succession, particularly of Paleocene age, there are intervals with source rock characteristics appropriate for generation of liquid and gas hydrocarbons.Bulk parameters show a medium to highly paraffinic, non-waxy oil seeps with API between 12.69° and 43.17°, sulfur content varying between 0.1100 and 1.6501 wt %. The ™13C isotopic composition of saturate fraction ranges between −28.9 and −22.2‰, while the aromatic fraction has a range of −28.80 to −22.70‰, and C.V. between −5.55 and −0.652, indicating non-waxy marine oils. Most of the samples analyzed by HRGC/FID and SIM-GC/MS in both whole oil and C15 + fractions showed a severe biodegradation process characterized by the total absence of n-alkanes and isoprenoids, the presence of an intense UCM, regular and ââ-steranes in low concentration, and presence of 25-norhopanes.The saturated fraction in condensate and light oil seeps analyzed by GC/FID presents a unimodal distribution between n-C10 to n-C33 with n-C15 to n-C17 as the major peaks. CPI is close or slightly greater than 1.0, Pr/Ph ratio >1.5 indicating an input of algal/microbial organic matter with a significant input of terrestrial matter. Biomarkers showed higher concentration of hopanes over tricyclic terpanes, Ts/Ts + Tm is > 0.25, O.I. ranges between 0.26 and 6.38 suggesting that the organic matter was deposited in a marine or marine deltaic environment during the Tertiary and/or Late Cretaceous. The C26TT/C25 TT ratio indicates both marine and non-marine organic sources. The alternate predominance of sterane distribution between C27- and C29-Steranes indicates that samples have marine, terrestrial or mixed characteristics. Diasterane/Sterane ratio suggests both a carbonate and siliciclastic lithology. Thermal maturity, according to the 20S/20S + 20R-C29 and ââ/áá+ââ-C29 steranes, adamantane and diamantane distribution and aromatic parameters, such as MPI, Rc, %, MNR, MPR, and MDBR indicate a low to moderated maturity.The results obtained indicate that additionally to the Late Cretaceous Cansona Formation, the Paleogene Arroyo Seco Formation could generate liquid hydrocarbons in the basin, and that the Neogene stratigraphic sequence is gas-prone. The presence of multiple potential source rocks for oil and gas generation in the basin open a new spectrum of exploration opportunities in conventional and unconventional petroleum systems associated with the Cenozoic, increasing the potential prospectivity of this under-explored basin.

Feasible D1–A–D2–A Random Copolymers for Simultaneous High‐Performance Fullerene and Nonfullerene Solar Cells

AbstractA series of PBDB‐TTn random donor copolymers is synthesized, consisting of an electron‐deficient benzo[1,2‐c:4,5‐c′]dithiophene‐4,8‐dione (BDD) unit and different ratios of two electron‐rich benzo[1,2‐b:4,5‐b′]dithiophene (BDT) and thieno[3,2‐b]thiophene (TT) units, with intention to modulate the intrachain and/or interchain interactions and ultimately bulk‐heterojunction morphology evolution. A comparative study using 4 × 2 polymer solar cell (PSC) performance maps and each of the [6,6]‐phenyl‐C71‐butyric acid methyl ester (PC71BM) and the fused‐aromatic‐ring‐based molecule (m‐ITIC) acceptors are carried out. Given the similarities in their absorption ranges and energy levels, the PBDB‐TTn copolymers clearly reveal a change in the absorption coefficients upon optimization of the BDT to TT ratio in the backbone. Among the given acceptor combination sets, superior performances are observed in the case of PBDB‐TT5 blended with PC71BM (8.34 ± 0.10%) or m‐ITIC (11.10 ± 0.08%), and the dominant factors causing power conversion efficiency differences in them are found to be distinctly different. For example, the performances of PC71BM‐based PSCs are governed by size and population of face‐on crystallites, while intermixed morphology without the formation of large phase‐separated aggregates is the key factor for achieving high‐performance m‐ITIC‐based PSCs. This study presents a new sketch of structure–morphology–performance relationships for fullerene‐ versus nonfullerene‐based PSCs.

Imaging of fetal thymus in pregnant women with rheumatic diseases

OBJECTIVE To determine whether certain rheumatic diseases will affect the fetal thymus diameter when compared to uncomplicated singleton pregnancies. Additionally, we created a reference chart for fetal thymus size in healthy singleton pregnancies from 19 to 37 weeks of gestation. METHODS Sonographic fetal thymus size was retrospectively evaluated in 190 healthy pregnant women, and 84 pregnancies of mothers suffering from systemic lupus erythematosus, antiphospholipid syndrome (APS), or Sjogren's syndrome between 19 and 37 weeks of gestation. These fetuses were matched one-to-one for gestational age with control fetuses. The thymic-thoracic ratio (TT-ratio) was defined as the quotient of the anteroposterior thymic and the intrathoracic mediastinal diameter. RESULTS Rheumatic diseases often affect pregnancy outcome, especially in case of primary APS. The TT ratio of fetuses of mothers suffering from rheumatic disease was equal to controls (P=0.807). CONCLUSIONS Ours is the first study to assess the correlation of fetal thymus size in high-risk pregnancies with rheumatic diseases in comparison to controls. Women with rheumatic diseases deal with pregnancy complications more frequently than controls. Our data suggest that maternal rheumatic diseases do not affect the fetal thymus size.

Imaging of fetal thymus in pregnant women with rheumatic diseases

To determine whether certain rheumatic diseases will affect the fetal thymus diameter when compared to uncomplicated singleton pregnancies. Additionally, we created a reference chart for fetal thymus size in healthy singleton pregnancies from 19 to 37 weeks of gestation. Sonographic fetal thymus size was retrospectively evaluated in 190 healthy pregnant women, and 84 pregnancies of mothers suffering from systemic lupus erythematosus, antiphospholipid syndrome (APS), or Sjögren's syndrome between 19 and 37 weeks of gestation. These fetuses were matched one-to-one for gestational age with control fetuses. The thymic-thoracic ratio (TT-ratio) was defined as the quotient of the anteroposterior thymic and the intrathoracic mediastinal diameter. Rheumatic diseases often affect pregnancy outcome, especially in case of primary APS. The TT ratio of fetuses of mothers suffering from rheumatic disease was equal to controls (P=0.807). Ours is the first study to assess the correlation of fetal thymus size in high-risk pregnancies with rheumatic diseases in comparison to controls. Women with rheumatic diseases deal with pregnancy complications more frequently than controls. Our data suggest that maternal rheumatic diseases do not affect the fetal thymus size.

Investigative Clinical Study on Prostate Cancer Part IV: Exploring Functional Relationships of Total Testosterone Predicting Free Testosterone and Total Prostate-Specific Antigen in Operated Prostate Cancer Patients

Objectives: To explore, in operated prostate cancer patients, functional relationships of total testosterone (tt) predicting free testosterone (ft) and total PSA. Patients and Methods: 128 operated prostate cancer patients were simultaneously investigated for tt, ft and PSA before surgery. Patients were not receiving 5α-reductase inihibitors, LH-releasing hormone analogues and testosterone replacement treatment. Scatter plots including ft and PSA versus tt were computed in order to assess the functional relationship of the variables. Linear regression analysis of tt predicting ft and PSA was computed. Results: tt was a significant predictor of the response variable (ft) and different subsets of the patient population were assessed according to the ft to tt ratio. PSA was related to tt according to a nonlinear law. tt was a significant predictor of PSA according to an inversely nonlinear law and different significant clusters of the patient population were assessed according to the different constant of proportionality computed from experimental data. Conclusions: In our prostate cancer population, ft was significantly predicted by tt according to a linear law, and the ft/tt ratio was a significant parameter for assessing the different clusters. Also, tt was a significant variable predicting PSA by a nonlinear law and different clusters of the patient population were assessed by the different constants of proportionality. As a theory, we explain the nonlinear relation of tt in predicting PSA as follows: (a) the number of androgen-independent prostate cancer cells increases as tumor volume and PSA serum levels rise, (b) the prevalence of androgen-independent cells producing a substance which inhibits serum LH, and (c) as a result lower levels of serum tt are detected.

Mechanical determinants of early acute ventilatory failure in COPD patients: a physiologic study

The purpose of this study is to investigate the respiratory mechanics, breathing pattern, and pressure-generating capacity of respiratory muscles during the early phases of an acute exacerbation of COPD. Prospective study. Division of Emergency Critical Care and Chronic Ventilator Unit. A total of 24 COPD patients: nine patients requiring ventilatory support because of acute respiratory acidosis due to COPD exacerbation (NPPV group, pH 7.28 +/- 0.02); seven patients successfully managed with medical therapy only (SB group, pH 7.39 +/- 0.04); eight clinically stable, long term mechanically ventilated, COPD patients (IPPV group). Respiratory mechanics during a period of unsupported breathing. A rapid shallow breathing, in the presence of a high drive to breath and a high diaphragmatic tension-time index (TT(di)), was found in NPPV and IPPV groups compared to the SB group (f/V (T) ratio: 118 +/- 43 and 137 +/- 65, respectively, versus 37 +/- 12 breaths/min/L; P (0.1): 5.0 +/- 1.0 and 5.4 +/- 1.4, respectively, versus 2.2 +/- 0.2 cmH(2)O, TT(di): 0.168 +/- 0.035 and 0.161 +/- 0.039, respectively, versus 0.057 +/- 0.033); at variance, PEEPi(dyn) was greater in IPPV compared to the other two groups. A significant relationship was observed between TT(di) ratio and f/V (T) (Rho 0.756). During the early phases of an acute exacerbation, patients with COPD and acute respiratory failure had an imbalance between the decreased capacity of the respiratory muscles to generate pressure and the increased respiratory load. This imbalance was similar to that recorded in patients with COPD and chronic ventilatory failure. In both groups, the imbalance was associated with rapid shallow breathing. Among the mechanical constraints to ventilation, only PEEPi,dyn was different between acute and chronic patients with ventilatory failure.

Changes of Thyroid Function During Long-term hGH Therapy in GHD Children. A Possible Relationship with Catch-up Growth?

Growth hormone (GH) treatment in patients with GH deficiency (GHD) can determine changes in the thyroid function. The clinical significance of these changes remains controversial, and all studies have so far covered rather a short period--usually no longer than one year. To determine the effect of long-term recombinant hGH treatment in children with idiopathic GHD on the thyroid function. Nineteen prepubertal children (12 boys and 7 girls, mean age 9.2 +/- 3.1 years) with idiopathic GHD were studied and followed for twenty-four months. None of the patients showed multiple pituitary hormone deficiencies. Nineteen healthy children matched for age and sex acted as controls. Patients with GHD showed a significant increase in TT (3) at twelve months and in FT (3) at six and twelve months after starting GH treatment, with a significant decrease at eighteen and twenty-four months. TT (4) level decreased significantly at twelve months and increased significantly at eighteen and twenty-four months. FT (4) also decreased, but only slightly, after twelve months of hGH treatment, and then increased significantly at twenty-four months. TSH levels did not vary significantly during the course of therapy. TT (3)/TT (4) and FT (3)/FT (4) ratios increased significantly after six and twelve months of therapy and significantly decreased later, approaching pre-therapy values. The SDS of Growth Velocity (SDS-GV) increased remarkably during the first year of therapy and then decreased significantly during the second year, although it remained significantly higher than the pre-therapy values. TT (3) and TT (3)/TT (4) ratio displayed a significant correlation with SDS-GV at twelve months of therapy. In a multiple regression analysis with age, bone age, parental height, GH dose, TT (3,) TT (3)/TT (4), and the SDS of IGF-I, only the TT (3)/TT (4) ratio at twelve months of therapy (p < 0.001) was identified as a significant predictor of SDS-GV. Our data confirm that changes in thyroid function are present in GHD children during long-term hGH therapy. These changes probably resulted from the effect of hGH on the peripheral metabolism of thyroid hormones and appear to be transitory, disappearing during the second year of hGH treatment. We speculate on the functional significance of these changes, and in particular, on their role in catch-up growth after hGH therapy.

A comparative study of the immunogenicity of pneumococcal type 4 polysaccharide and oligosaccharide tetanus toxoid conjugates in adult mice.

A number of pneumococcal type 4 poly- and oligosaccharide tetanus toxoid conjugates were prepared using identical conjugation methods. Purified conjugates with similar m.w. were injected in mice; polysaccharide conjugates (PS4TT) were more immunogenic than oligosaccharide conjugates (OS4TT). Polysaccharide conjugates with a PS4:TT ratio less than 1 (w/w) appeared to be the most immunogenic conjugates. This was observed in both NIH (outbred) and BALB/c (inbred) strains of mice. Oligosaccharide tetanus toxoid conjugates required w/w ratios of greater than 1 to acquire optimal immunogenicity. Oligosaccharides (12 repeating units) of pneumococcal type 4, obtained by periodate cleavage, appeared to retain full antigenicity as measured by competition ELISA. Both PS4TT and OS4TT conjugates induced an antibody response with the characteristics of a T cell-dependent type of immune response. An anti-PS4 IgG and IgM booster effect could be demonstrated for all conjugates. The IgG subclass response induced by PS4TT and OS4TT conjugates is primarily IgG1 but IgG3 is also detectable. However, the amounts of anti-PS4 IgG3 differed for the various conjugates. We conclude that the immune response induced by pneumococcal type 4 saccharide tetanus toxoid conjugates can be manipulated by variation of the saccharide:protein ratio and the saccharide chain length, whereas keeping the m.w. of such conjugates at constant values.