The effect of previous orbital decompression on outcomes of rectus muscle recession surgery in patients with thyroid ophthalmopathy

PURPOSE

To evaluate the effect of previous orbital decompression on outcomes of rectus muscle recession surgery in patients with thyroid-associated ophthalmopathy.

METHODS

This retrospective study enrolled 55 eyes of 33 patients treated in our hospital for restrictive strabismus caused by thyroid-associated ophthalmopathy. We performed muscle recession for the obviously restricted extraocular muscles, with 6 weeks of follow-up. Surgical outcomes were compared between the orbital decompression group (DG, n=15) and non-orbital decompression group (NDG, n=18).

RESULTS

A total of 33 patients with Graves' ophthalmopathy who underwent rectus muscle recession surgery were included. Of these, 15 patients had undergone orbital decompression prior to strabismus surgery, and 18 had not. The two groups did not differ in terms of the preoperative horizontal or vertical ocular deviation, degree of restriction of eye movement, degree of diplopia, or mean number of muscles that underwent surgery (P>0.05). There was no significant difference in the preoperative horizontal or vertical ocular deviation, level of eye movement restriction, degree of diplopia and the success rate of the surgery (P>0.05).

CONCLUSION

Rectus muscle recession surgery in patients with thyroid-associated ophthalmopathy during the quiescent period could improve the ocular deviation and diplopia, and orbital decompression performed before strabismus surgery had no significant effect on surgical technique or outcomes of rectus muscle recession surgery.

The causal effects of age at menarche, age at first live birth, and estradiol levels on systemic lupus erythematosus: A two-sample Mendelian randomization analysis

OBJECTIVES

To determine whether age at menarche (AAM), age at first live birth (AFB), and estradiol levels are causally correlated with the development of systemic lupus erythematosus (SLE).

METHODS

A two-sample Mendelian randomization (MR) analysis was performed after data was collected from a dataset of genome-wide association studies (GWASs) related to SLE (as outcome), and from open access databases to find statistics related to AAM, AFB, and estradiol levels (as exposure).

RESULT

In our study, a negative causal correlation between AAM and SLE was confirmed by MR analysis (MR egger: beta = 0.116, SE = 0.948, p = 0.909; weighted median: beta = -0.416, SE = 0.192, p = 0.030; and IVW: beta = -0.395, SE = 0.165, p = 0.016). However, there were no genetic causal effects of AFB and the estradiol levels on SLE, based on the results of MR analysis as follows: AFB (MR egger: beta = - 2.815, SE = 1.469, p = 0.065; Weighted median: beta = 0.334, SE = 0.378, p = 0.377; and IVW: beta = 0.188, SE = 0.282, p = 0.505) and the estradiol levels (MR egger: beta = 0.139, SE = 0.294, p = 0.651; weighted median: beta = 0.063, SE = 0.108, p = 0.559; IVW: beta = 0.126, SE = 0.097, p = 0.192).

CONCLUSIONS

Our findings revealed that AAM may be associated with increased risk of the development of SLE, while there were no such causal effects from AFB and estradiol levels.

Value of magnetic resonance imaging and sialography of the parotid gland for diagnosis of primary Sjögren syndrome

AIM

To evaluate the utility of magnetic resonance imaging (MRI) and magnetic resonance sialography (MRS) for diagnosis of primary Sjögren syndrome (pSS) singly or integrated with 2016 American College of Rheumatology (ACR)/European League Against Rheumatic Diseases (EULAR) classification criteria.

METHODS

The diagnostic efficiencies of MRI, MRS, and labial salivary gland biopsy (LSGB) were evaluated. The prediction model was established by multivariate analysis. Finally, performance of the ACR/EULAR criteria was evaluated after addition of MRI + MRS or replacement of original items by MRI + MRS.

RESULTS

The combined use of LSGB + MRI + MRS provided the greatest diagnostic value. MRI and MRS grade had positive correlations with disease duration and pathological grade of the labial gland (both P < 0.001). MRI and MRS grade had positive correlations with xerostomia severity and negative correlations with unstimulated salivary flow rate (both P < 0.001). The consistency of MRI grade and MRS grade in the diagnosis of parotid gland lesions was poor (κ = 0.253, P < 0.001). The diagnostic efficiency of our prediction model (AUC 0.906) was similar to that of criteria from the ACR/EULAR (AUC 0.930). Adding MRI + MRS to the ACR/EULAR criteria improved the sensitivity (92.3% vs 90.8%), whereas the specificity remained the same (88.9% vs 89.1%). Replacing LSGB by MRI + MRS in the ACR/EULAR criteria decreased both sensitivity and specificity (88.1% vs 90.8% and 86.4% vs 89.1%, respectively).

CONCLUSION

The combined application of MRI and MRS has ideal clinical application value in the diagnosis of early-stage pSS. Validity of the ACR/EULAR criteria remains high after incorporation of MRI + MRS.

[Evaluation of the role of melatonin in the metastasis of papillary thyroid carcinoma]

Objective:To evaluate the level of melatonin and the role of melatonin in the metastasis of papillary thyroid carcinoma in patients with papillary thyroid carcinoma. Method:We measured serum melatonin levels in 81 patients with papillary thyroid carcinoma（PTC） ,20 patients with multinodular goiter（MNG） and 20 healthy adults using ELISA. The relationship between melatonin and clinicopathological features of PTC were analyzed.The expression of MT1 and MT2 in two subtypes of melatonin receptor in 81 cases of papillary thyroid carcinoma and adjacent tissues were detected by immunohistochemical SP method, and its the mean optical density（MOD） image was analyzed by Image Pro Plusversion（IPP） image processing software. Result:Serum melatonin concentration in patients with PTC was significantly higher than that in MNG patients and normal controls（P<0.05）. The level of melatonin in the primary tumor T≥2 cm group was significantly higher than that in the T<2 cm group. Patients with positive cervical lymph nodes（N≥1） had significantly higher melatonin levels than lymph node negatives（N=0）（P<0.05）. The MT1 and MT2 receptors were expressed in both PTC and paracancerous tissues, mainly in the cell membrane and cytoplasm. The expression of MT1 receptor was low in the two groups, and there was no statistical difference. The expression of MT2 receptor in PTC tissues Significantly higher than the adjacent tissues（P<0.05）, further studies showed that the expression of MT2 receptor in PTC tissues was associated with cervical lymph node metastasis, and the expression of MT2 receptor in PTC tissues with cervical lymph node metastasis was significantly lower than that without metastasis （P<0.05）. Conclusion:Serum melatonin levels in PTC patients were higher than those in MNG and control groups, which may be associated with low malignancy of PTC; melatonin inhibits PTC metastasis, which exerts anti-PTC metastasis mainly through MT2 receptors.

[Clinical study about anatomical and functional reconstruction for frontolateral vertical partial laryngectomy with ultrathin titanium mesh and fascia flap from the strap muscles]

Objective:To investigate the effect of laryngeal reconstruction in functional and anatomical aspect with ultrathin titanium mesh and myofascial flap in patients underwent frontolateral vertical partial laryngectomy with T2 and T3 glottic laryngeal carcinoma. Method:Ten patients with T2 and T3 glottic laryngeal carcinoma underwent frontolateral vertical partial laryngectomy in different range. The ultrathin titanium mesh was shaped up according to the form of thyroid cartilage in operation while the thyroid perichondrium membrane combined with straped myofascial flap was lined under the titanium mesh to restore the laryngeal cavity space. The pronunciation, swallowing capability and extubation rate were observed after surgery. Result:Nine patients underwent extubation within 2 to 4 weeks after surgery, one patients remove metal tube in two-stage after laryngeal dilation surgery with the Montgomery tube. Swallowing and voice function in these patients recovered well and no deglutition disorder was found. CT scan showed that the Titanium meshs were fixed well without displacement and deformity. Electronic laryngoscopy showed that the mucosa of laryngeal lumen was smooth without laryngeal stenosis, keloid contraction, tissue necrosis or titanium mesh exposure. Conclusion:In the cases of T2, T3 glottic laryngeal cancer patients, laryngeal framework reconstruction with the new type of ultrathin titanium mesh, thyroid cartilage membrane and pedicled fascia plap of strap muscles is a good choice after the vertical frontolateral partial laryngectomy. Even some elective T4 cases with the former part invasion in supra-glottic or infra-glottic region can receive this operation. It can reconstruct the physiological and anatomical structure of the larynx, restore laryngeal function with a sound decanulization rate.

[The anatomic characteristics and surgical treatment of congenital pyriform sinus fistula]

Objective:To discuss the clinical anatomic characteristics of congenital pyriform sinus fistula and summarize the experiences of open neck surgery. Method：The clinical data of 12 patients with congenital pyriform sinus fistula were retrospectively analyzed.Result:During the operation, all lesions were located below of superior laryngeal nerve. All fistulas were closely related with the supperior part of thyroid gland and laterally passed over the left recurrent laryngeal nerve just before merging into the apex of piriform sinus or beginning of aesophagus. Follow-up periods were ranging between 8 to 65 months. Two months after surgery,one patient showed lateral neck abscess again. After open drainage procedures and antibiotics treatment, there was no recurrence signs during 3 years of follow-up.Conclusion:We found that the congenital pyriform sinus fistula was closely related to the superior thyroid gland and recurrent laryngeal nerve,which was different from the popular theory.We had not encountered types descending into mediastinum and thoracic cavity or ascending along common carotid artery sheath. All fistulas passed over the left recurrent laryngeal nerve，and then merged into the apex of pyriform sinus or beginning of aesophagus.The key point for successful resection of fistulas in block was to remove the superior involvement part of the thyroid gland and exposure the recurrent laryngeal nerve. Based on our practical findings, the neck dissection procedure should not be taken in some patients that the anatomical structure is not clear for repeated infections.

[Primary malignant tumor of uvula: report of 3 cases and review of the literature]

We retrospectively analyzed 3 middle-aged male patients of primary malignant tumor of uvula. There was a long history of smoking and drinking for the patients. All of them came to the hospital with the syptoms of pharyngeal foreign body sensation and two of them had pharyngeal sore. The patients appeared well, new neoplasm at the apex of the uvula. Diameter of 2 cases were less than 1 cm without invading the midline of the soft palate. Another patient's diameter was more than 1 cm with invading the midline of the soft palate. Preoperative pathology diagnosis of 3 patients was squamous cell carcinoma of uvula. The pharyngeal CT of the patient with invading the midline of the soft palate showed nodules at the end of the soft palate, obviously enhancement and small lymph node in left neck.

Anatomical structure of the coracohumeral ligament and its effect on shoulder joint stability

BACKGROUND

In this study, coracohumeral ligament (CHL) specimens were carefully dissected to observe its length, width, thickness and tension at different positions of the shoulder joint, thereby elucidating its effects on shoulder joint stability.

MATERIALS AND METHODS

Fresh frozen shoulder joints from 40 normal adult cadaveric specimens were dissected to reveal the CHL. With the shoulder joints placed at different positions, the length of the CHL and the width and thickness of the middle part of the ligament were measured. The changes in tension of the CHL were also observed. When the shoulder joint maintained the neutral position, the length of the CHL was 52.23 ± 1.02 mm and the width and thickness of the middle part of the ligament were 15.95 ± 0.59 mm and 1.46 ± 0.06 mm, respectively.

RESULTS

When the shoulder joint moved from the neutral position to 90° external rotation, from the neutral position to 30° adduction or from the neutral position to 30° flexion/extension or when the shoulder joint is pulled down with a 5 kg weight, the CHL was elongated and thinned, maintaining a strained state. When the shoulder joint moved from the neutral position to 90° internal rotation, from the neutral position to 90° abduction or from the neutral position to 30° flexion/ extension, the CHL was shortened and thickened, maintaining a relaxed state.

CONCLUSIONS

The CHL may limit the external rotation, adduction and downward movement of the shoulder joint and the process from the neutral position to the 30° flexion/extension, maintaining shoulder joint stability.

Therapy of tacrolimus combined with corticosteroids in idiopathic membranous nephropathy

We evaluated the efficacy and safety of tacrolimus (TAC) combined with corticosteroids in treating patients with idiopathic membranous nephropathy (IMN). One hundred seventy-seven biopsy-proven IMN patients were recruited in this retrospective clinical study. Sixty patients received TAC (target blood concentration of 4–8 ng/mL) and 117 patients received daily cyclophosphamide (CYC, 100 mg) combined with prednisone. Remission rates at the end of the first, second and third month in the TAC group were significantly higher than that in the CYC group (1st: 35.0 vs 19.7%, P<0.05; 2nd: 56.7 vs 38.5%, P<0.05; 3rd: 76.7 vs 59.0%, P<0.05). In the first 3 months, daily urinary protein and serum albumin in the TAC group obtained a better improvement than that in the CYC group (P<0.05). At the end of the sixth and the twelfth month, the remission rates, daily urinary protein and serum albumin were all comparable between the two groups (P>0.05). No significant difference of relapse rate between the groups was found (16.3 vs 12.0%, P>0.05). Patients were more likely to develop glucose intolerance in the TAC group. The TAC regimen obtained more benefits in treating IMN patients, especially in the first 3 months, than the CYC regimen.

Environmental context for the terminal Ediacaran biomineralization of animals

In terminal Ediacaran strata of South China, the onset of calcareous biomineralization is preserved in the paleontological transition from Conotubus to Cloudina in repetitious limestone facies of the Dengying Formation. Both fossils have similar size, funnel-in-funnel construction, and epibenthic lifestyle, but Cloudina is biomineralized, whereas Conotubus is not. To provide environmental context for this evolutionary milestone, we conducted a high-resolution elemental and stable isotope study of the richly fossiliferous Gaojiashan Member. Coincident with the first appearance of Cloudina is a significant positive carbonate carbon isotope excursion (up to +6‰) and an increase in the abundance and (34) S composition of pyrite. In contrast, δ(34) S values of carbonate-associated sulfate remain steady throughout the succession, resulting in anomalously large (>70‰) sulfur isotope fractionations in the lower half of the member. The fractionation trend likely relates to changes in microbial communities, with sulfur disproportionation involved in the lower interval, whereas microbial sulfate reduction was the principal metabolic pathway in the upper. We speculate that the coupled paleontological and biogeochemical anomalies may have coincided with an increase in terrestrial weathering fluxes of sulfate, alkalinity, and nutrients to the depositional basin, which stimulated primary productivity, the spread of an oxygen minimum zone, and the development of euxinic conditions in subtidal and basinal environments. Enhanced production and burial of organic matter is thus directly connected to the carbon isotope anomaly, and likely promoted pyritization as the main taphonomic pathway for Conotubus and other soft-bodied Ediacara biotas. Our studies suggest that the Ediacaran confluence of ecological pressures from predation and environmental pressures from an increase in seawater alkalinity set the stage for an unprecedented geobiological response: the evolutionary novelty of animal biomineralization.

Association of CYP1A1 MspI polymorphism with oral cancer risk in Asian populations: a meta-analysis

Numerous studies regarding the association between the CYP1A1 MspI polymorphism and oral cancer risk in Asian populations have shown controversial results. To get a more precise estimation of this relationship, we conducted a comprehensive meta-analysis. PubMed, the Cochrane Library, Elsevier Science Direct, Web of Knowledge, the Chinese National Knowledge Infrastructure, VIP, and Wan Fang Med Online were searched. Pooled odds ratios (ORs) with 95% confidence intervals (95%CIs) were calculated using fixed-effects or random-effects models. Heterogeneity among studies was assessed using the Cochran Q test and I(2) statistics. Twelve articles including 1925 oral cancer patients and 2335 controls were ultimately included in the meta-analysis. Overall, the meta-analysis showed that the CYP1A1 MspI polymorphism was associated with oral cancer risk in Asians (m1/m1 vs m2/m2: OR = 0.46, 95%CI = 0.30-070, POR = 0.000; m1/m1 vs m1/m2+m2/m2: OR = 0.70, 95%CI = 0.51-0.98, POR = 0.037; m1/m1+m1/m2 vs m2/m2: OR = 0.48, 95%CI = 0.35-0.65, POR = 0.000). Subgroup analyses showed that the control source (hospital-based or population-based), the genotyping method [polymerase chain reaction (PCR) or PCR-restriction fragment length polymorphism], the country in which the study was conducted, and Hardy-Weinberg equilibrium (Yes or No) were positively related to the association. Sensitivity analysis suggested that the overall results showed no significant change in three genetic models when any one study was removed, and publication bias was undetected by the Egger test. The CYP1A1 MspI polymorphism may be associated with oral cancer risk in Asian populations.

[The resection of a giant recurrent parotid gland tumor]

This paper report a case of a giant recurrent tumor arising in the parotid gland. The patient presents as a tumor for 20 years on her left parotid region showing a rapid increase in the dimensions during the latest 3 months. The computed tomography scan and fine needle aspiration cytology (FNAC) showed it most likely to be a pleomorphic adenoma. The tumor was completely resected with preservation of the facial nerve under general anesthesia. Macroscopically, the excised tumor was measured 21 cm×13 cm×10 cm in scale, and weighed 1.730 kg. Histopathological examination of the excised tumor revealed a recurrent pleomorphic adenoma. Postoperatively, the facial nerve function was normal with an excellent aesthetic outcome.

Effect of oral contraceptive use on the incidence of dry socket in females following impacted mandibular third molar extraction: a meta-analysis

The aim of this comprehensive meta-analysis was to provide evidence-based data to test whether oral contraceptive (OC) use can promote the incidence of dry socket (DS) in females following impacted mandibular third molar extraction. PubMed, the Cochrane Library, and Elsevier Science Direct databases were searched. The pooled risk ratio (RR) with 95% confidence interval (CI) was calculated using fixed-effects or random-effects model analysis. Heterogeneity among studies was evaluated with the Cochran test and I(2) statistic. Study quality was assessed with the Newcastle-Ottawa scale. Of 70 articles identified in the search, 12 reporting 16 clinical controlled trials were included in this study. The incidence of DS was significantly greater in the OC groups than in the control groups (RR 1.80, 95% CI 1.33-2.43). Subgroup analyses showed that the unit assessed (tooth or patient), the region in which the study was conducted, and the intervention were not related to the incidence of DS in females taking OC after impacted mandibular third molar extraction. The sensitivity analysis showed no significant change when any one study was excluded. Publication bias was also not detected. This study suggests that OC use may promote the incidence of DS in females following impacted mandibular third molar extraction.

Molecular cloning and expression patterns of three putative functional aldehyde oxidase genes and isolation of two aldehyde oxidase pseudogenes in tomato

The final steps in the biosynthesis of the plant hormones abscisic acid (ABA) and indole-3-acetic acid (IAA) have been shown to be catalyzed by aldehyde oxidases (AO). We have cloned three putative functional AO genes (TAO1, TAO2 and TAO3) and two putative AO pseudogenes (TAO4 and TAO5) in tomato. The TAO1 cDNA described here includes the correct amino terminus of the encoded TAO1 protein and is different at the 5'-end from the TAO1 sequence in GenBank (accession number U82558). Northern analysis shows that TAO1 is expressed mainly in vegetative tissues and TAO2 is expressed in both vegetative and reproductive tissues. TAO3 expression was not detectable by Northern hybridization. These results suggest that each AO may play different roles in the regulation of tomato growth and development.

Conformational basis of the phospholipid requirement for the activity of SR Ca(2+)-ATPase

The delipidated sarcoplasmic reticulum (SR) Ca(2+)-ATPase was reconstituted into proteoliposomes containing different phospholipids. The result demonstrated the necessity of phosphatidylcholine (PC) for optimal ATPase activity and phosphatidylethanolamine (PE) for the optimal calcium transport activity. Fluorescence intensity of Fluorescein 5-isothiocyanate (FITC)-labeled enzyme at Lys515 as well as the measurement of the distance between 5-((2-[(iodoacetyl) amino] ethyl) amino)naphthalene-1-sulphonic acid (IAEDANS) label sites (Cys674/670) and Pr3+ demonstrated a conformational change of cytoplasmic domain, consequently, leading to the variation of the enzyme function with the proteoliposomes composition. Both the intrinsic fluorescence of Trp and its dynamic quenching by HB decreased with increasing PE content, revealing the conformational change of transmembrane domain. Time-resolved fluorescence study characterized three classes of Trp residues, which showed distinctive variation with the change in phospholipid composition. The phospholipid headgroup size caused the conformational change of SR Ca(2+)-ATPase, subsequent the ATPase activity and Ca2+ uptake.

Finite element analysis of defibrillation fields in a human torso model for ventricular defibrillation

In order to optimize defibrillation electrode systems for ventricular defibrillation thresholds (DFTs), a Finite Element Torso model was built from fast CT scans of a patient who had large cardiac dimensions (upper bound of normal) but no heart disease. Clinically used defibrillation electrode configurations, i.e. Superior Vena Cava (SVC) to Right Ventricle (RV) (SVC-RV), left pectoral Can to RV (Can-RV) and Can + SVC-RV, were analyzed. The DFTs were calculated based on 95% ventricular mass having voltage gradient > 5 V/cm and these results were also compared with clinical data. The low voltage gradient regions with voltage gradient < 5 V/cm were identified and the effect of electrode dimension and location on DFTs were also investigated for each system. A good correlation between the model results and the clinical data supports the use of Finite Element Analysis of a human torso model for optimization of defibrillation electrode systems. This correlation also indicates that the critical mass hypothesis is the primary mechanism of defibrillation. Both the FEA results and the clinical data show that Can + SVC-RV system offers the lowest voltage DFTs when compared with SVC-RV and Can-RV systems. Analysis of the effect of RV, SVC and Can electrode dimensions and locations can have an important impact on defibrillation lead designs.

Effect of the Yang tonifying herbs on myocardial beta-adrenoceptors of hypothyroid rabbits

New Zealand White female rabbits were randomly divided into three groups, each contained six rabbits, i.e. thyroidectomized and untreated rabbits (group 1), thyroidectomized rabbits treated by the Yang tonifying herbs (group 2) and sham thyroidectomized rabbits as controls (group 3). The myocardial beta-adrenoceptor density (Bmax) and affinity (Kd) of each group of rabbits were determined by radioligand binding assay technique on the thirtieth postoperative day and the data were handled by using a computer program of the Woolf plot with weight regression. Moreover, the serum levels of thyroxine (T4) and triiodothyronine (T3) of each group of rabbits were measured by radioimmunoassay technique and their heart rates (HR) were also recorded on the preoperative and thirtieth postoperative day. The results showed that the Bmax, T4, T3 and HR in group 1 were lower significantly than that in group 3 (P < 0.01-0.001), but the change of Kd in group 1 was not significant; the deviation of the indices from the normal value in group 2 was less remarkably than in group 1 other than T4.

An integral equation model for intracardiac electrogram sensing

Electrogram sensed by an intracardiac electrode has long been characterized based on two approaches: 1) presume that the electrode is very small and does not disturb the potential prior to applying the electrode, and 2) take an average of the prior potential over the electrode surface. In fact, any intracardiac sensing electrode has a finite surface area where electrical charges are induced and disturb the external potential field, thus, the sensed potential is different from the potential prior to placing the electrode. In this paper, an integral equation model is proposed based on the current continuity equation in homogeneous myocardial medium. The new model can accurately characterize the electrogram sensed by an electrode with a non-negligible surface area and a load impedance. The new model can be solved numerically via the method of moments to obtain the potential induced on the electrode surface by an arbitrary dipole volume source. As an application of the proposed theory, several electrode configurations with different loads have been analyzed with an intent to show that a finite electrode surface will significantly reduce the electrogram peak amplitude and slope, and a load impedance lower than 20 k omega will also degrade the electrogram sensitivity.

Random mutagenesis of the human immunodeficiency virus type-1 trans-activator of transcription (HIV-1 Tat)

A new method is described for the direct construction of randomly mutagenized genes by applying the polymerase chain reaction (PCR) to an oligonucleotide synthesized using doped nucleotide reservoirs. We have demonstrated the utility of this method by generating a library of mutant HIV-1 tat genes. Several arbitrarily selected, inactive tat clones were sequenced to evaluate the extent of the mutagenesis. Moreover, fourteen recombinants encoding varying levels of transcriptional trans-activator activity were isolated by transient transfection of sub-library pools into a HeLa cell line bearing an HIV-LTR-chloramphenicol acetyltransferase (CAT) reporter gene. Sequence data revealed a spectrum of alterations including nucleotide substitutions, insertions, and deletions, suggesting that mutations arose from both the doped DNA synthesis and the subsequent PCR 'rescue' of full-length product. Sequence comparison between inactive and active Tat clones revealed a selection pressure against amino-acid substitutions within the N-terminal domains of Tat, indicating the importance of this region to trans-activation competence. In addition, single and double missense mutations within the basic-rich, TAR RNA-binding domain were seen to be tolerated within active Tat clones.

Expansion of myelopoietic precursors and inhibition of B-cell precursors in mice that express a T-cell receptor gamma (V gamma 1.1J gamma 4C gamma 4) transgene

Knowledge of the genetic determinants that can affect renewal of multipotential stem cells and their commitment to specific cell lineages is essential to our understanding of multicellular development. However, despite the vast amount of accumulated knowledge in this area, genetic determinants that affect renewal and commitment of precursor cells are unknown. In this study, we demonstrate that three independently derived founder mouse strains, transgenic for the TcR V gamma 1.1J gamma 4C gamma 4 (TcR gamma 4) chain gene, differed significantly from normal mice in their development of T and B cells as well as myelopoietic precursor cells. Ontogenic programs consistent with an acceleration of T-cell development and a delayed appearance and suppressed levels of pre-B- and B-cell precursors were evident in these transgenic mice. In addition, TcR gamma 4 transgenic mice possessed a significantly elevated level of myelopoietic pluripotential precursors. 3H-thymidine cell suicide studies suggest that higher percentages of pluripotent precursors from the bone marrow of the TcR gamma 4 transgenic mice were in the S phase of the cell cycle. These modulations of the lymphoid and myelopoietic compartments, however, were not found in other T-cell receptor transgenic mice (e.g., TcR V gamma 1.2J gamma 2C gamma 2, TcR gamma 2; or V beta 8.1D beta J beta 2.4C beta 2, TcR beta) constructed with the same or similar cDNA expression vector. The results suggest that the expression of a specific T-cell receptor gamma chain gene, and/or an elevated level of particular subset of TcR gamma delta cells, may affect the proliferation and relative proportions of haemopoietic and lymphoid precursors.

Detection of amplified Wuchereria bancrofti DNA in mosquitoes with a nonradioactive probe

A technique to identify Wuchereria bancrofti larvae in mosquito vectors with an enzyme-labeled DNA probe is described. To overcome the low sensitivity of nonradioactive detection methods, analyte DNA was amplified by polymerase chain reaction (PCR). Oligonucleotide primers were used to amplify W. bancrofti-specific DNA fragments of 380 and 650 bp, respectively. Parasite DNA in mosquito extracts was isolated free of inhibitors of the PCR by hybridization to a biotinylated DNA fragment (IWb 67), which hybridizes to DNA from most filarial species, followed by absorption of the resulting DNA hybrids onto avidin-coated acrylic beads. PCR-amplified DNA was detected with a biotin-labeled W. bancrofti-specific repeat DNA (IWb 35) coupled to avidin-alkaline phosphatase and the chemiluminescent substrate, AMPPD. The DNA equivalent of less than one larva can be detected by this method in mosquito extracts. The sensitivity of detection was comparable to that of radioactive probes and the assay is suitable for field application in endemic countries.