Systems genetics uncover new loci containing functional gene candidates in Mycobacterium tuberculosis-infected Diversity Outbred mice

Mycobacterium tuberculosis, the bacillus that causes tuberculosis (TB), infects 2 billion people across the globe, and results in 8-9 million new TB cases and 1-1.5 million deaths each year. Most patients have no known genetic basis that predisposes them to disease. We investigated the complex genetic basis of pulmonary TB by modelling human genetic diversity with the Diversity Outbred mouse population. When infected with M. tuberculosis, one-third develop early onset, rapidly progressive, necrotizing granulomas and succumb within 60 days. The remaining develop non-necrotizing granulomas and survive longer than 60 days. Genetic mapping using clinical indicators of disease, granuloma histopathological features, and immune response traits identified five new loci on mouse chromosomes 1, 2, 4, 16 and three previously identified loci on chromosomes 3 and 17. Quantitative trait loci (QTLs) on chromosomes 1, 16, and 17, associated with multiple correlated traits and had similar patterns of allele effects, suggesting these QTLs contain important genetic regulators of responses to M. tuberculosis. To narrow the list of candidate genes in QTLs, we used a machine learning strategy that integrated gene expression signatures from lungs of M. tuberculosis-infected Diversity Outbred mice with gene interaction networks, generating functional scores. The scores were then used to rank candidates for each mapped trait in each locus, resulting in 11 candidates: Ncf2, Fam20b, S100a8, S100a9, Itgb5, Fstl1, Zbtb20, Ddr1, Ier3, Vegfa, and Zfp318. Importantly, all 11 candidates have roles in infection, inflammation, cell migration, extracellular matrix remodeling, or intracellular signaling. Further, all candidates contain single nucleotide polymorphisms (SNPs), and some but not all SNPs were predicted to have deleterious consequences on protein functions. Multiple methods were used for validation including (i) a statistical method that showed Diversity Outbred mice carrying PWH/PhJ alleles on chromosome 17 QTL have shorter survival; (ii) quantification of S100A8 protein levels, confirming predicted allele effects; and (iii) infection of C57BL/6 mice deficient for the S100a8 gene. Overall, this work demonstrates that systems genetics using Diversity Outbred mice can identify new (and known) QTLs and new functionally relevant gene candidates that may be major regulators of granuloma necrosis and acute inflammation in pulmonary TB.

Long-term outcomes of conventional core decompression for osteonecrosis of the femoral head in systemic lupus erythematosus: a single-center retrospective study

OBJECTIVE

Although the therapeutic efficacy of conventional core decompression (CD) for the early-stage osteonecrosis (ON) has been widely investigated in the literature, no study to date has specifically focused on its therapeutic effect on the long-term outcome of ON of the femoral head (ONFH) in systemic lupus erythematosus (SLE). This study aimed to provide a long-term survival analysis of all hips that underwent conventional CD for the management of ONFH in a consecutive case series of patients with SLE.

PATIENTS AND METHODS

Sixteen hips of 10 consecutive SLE patients that underwent conventional CD for the management of ONFH in a single tertiary referral center were retrospectively identified and included in the study. After a retrospective chart review, several clinical and radiological data were recorded.

RESULTS

All the hips treated with CD were stage I or IIA sclerotic and/or cystic based on the classification system of Ficat. Only the 2 hips of 1 patient (12.5%) survived both clinically and radiographically. The median overall survival for all hips after CD was 80 months (95% CI, 60-100). The 5-, 10-, and 15- year survival rates of hip joints following CD were 63%, 31%, and 12.5%, respectively (CI 95% 63.567 to 133.058 months).

CONCLUSIONS

Conventional CD may not be effective in preventing the progression of pre-collapse ONFH to collapse and eventually end-stage osteoarthritis requiring arthroplasty in patients with SLE.

The importance of size of cervical ectopy to predict postcoital bleeding: is there any cut-off value?

OBJECTIVE

To investigate the relationship between size of cervical ectopy and existence of postcoital bleeding (PCB) in non-symptomatic women.

MATERIALS AND METHODS

Study population were recruited from women ages 18-65 years, sexually active who applied to the present outpatient department. They were asked whether they had had postcoital bleeding in the last three months. After ful visualization of the cervix, the existence of ectopy was noted and measured. The smears were taken from all patients with endobrushes.

RESULTS

The authors found a relationship between the size of ectopy and PCB. In the prediction of PCB, the lesion's size (of both antero-posterior and transverse diameters) of 3.5 mm as the cut off level, sensitivity, and specificity were found to be 70% and 76%, respectively.

CONCLUSION

The full visualization of the cervix is important because of the relationship between the existence of ectopy and PCB.

Survival of an eight-year-old child with a very severe high-tension electrical burn injury: a case report

We present the management and survival of an eight-year-old boy with a severe high-tension electrical burn injury of 68% of total body surface area in a surgical intensive care unit, as a result of a well-planned and applied treatment strategy. Subsequent to escharotomy and fasciotomy operations under general anesthesia, the patient was taken into the surgical intensive care unit. In addition, patient underwent nine more operations including right femur disarticulation and split-thickness skin graftings with homografts from his brother and autografts. The patient was connected to mechanical ventilator for 59 days. By the time the patient was transferred to plastic and reconstructive surgery ward, he was fully conscious, cooperated and hemodynamically stable.

Effect of nimodipine on ocular blood flow and colour contrast sensitivity in patients with normal tension glaucoma

AIM

To investigate the effects of oral nimodipine on ocular haemodynamic parameters and colour contrast sensitivity in patients with normal tension glaucoma (NTG).

DESIGN

The study was performed in a randomised, placebo controlled, double masked, crossover design.

PARTICIPANTS

Nimodipine (60 mg) or placebo was administered to 14 consecutive NTG patients.

METHODS

The effects or oral nimodipine or placebo on ocular and systemic haemodynamic parameters and colour contrast sensitivity along the tritan axis were studied two hours after administration. Optic nerve head blood flow (ONHBF) and choroidal blood flow (CHBF) were assessed with laser Doppler flowmetry. Ocular fundus pulsation amplitude (FPA) was measured with laser interferometry. Colour contrast sensitivity (CCS) was determined along the tritan colour axis.

MAIN OUTCOME MEASURES

ONHBF, CHBF, FPA, intraocular pressure and CCS were assessed in patients with NTG.

RESULTS

Mean ocular FPA increased by 14% (SD 14%) (p = 0.0008), ONHBF by 18% (SD 16%) (p = 0.0031), and CHBF by 12% (SD 14%) (p<0.001) after administration of nimodipine. Nimodipine also decreased the threshold of colour contrast sensitivity along the tritan colour axis (-14% (SD 12%); p = 0.048). However, individual changes in FPA, ONHBF, or CHBF were not correlated with changes in threshold of CCS along the tritan colour axis.

CONCLUSIONS

The results indicate that nimodipine increases ONH and choroidal blood flow in NTG patients and improves CCS. The latter effect does not, however, seem to be a direct consequence of the blood flow improvement.

Ten-year follow-up of epikeratophakia for the correction of high myopia

OBJECTIVE

To determine the long-term functional results of epikeratophakia for myopic patients.

DESIGN

Retrospective, noncomparative, interventional case series.

PARTICIPANTS

Twenty-two patients (32 eyes; average age, 43+/-6 years) who underwent epikeratophakia surgery for high myopia. Mean preoperative myopia was -18.74+/-9.16 diopters (D; range, -7 D to -49 D). Follow-up was 12+/-2 years.

MAIN OUTCOME MEASURES

Uncorrected visual acuity (UCVA), best-corrected visual acuity (BCVA), change in mean keratometry, visual acuity under glare conditions, BCVA versus potential acuity meter reading, and patient satisfaction with the visual outcome.

RESULTS

Mean preoperative UCVA increased from 20/800+/-20/400 (range, counting fingers-20/400) to 20/80+/-20/200 (range, 20/250-20/32) in 24 eyes. Mean preoperative BCVA of 20/32+/-20/64 increased only in five eyes, whereas six eyes had no change and 18 eyes had a more than one line loss of Snellen BCVA. Mean preoperative keratometry reading decreased from 43.67+/-0.90 D (range, 41.0-46.25 D) to 37.40+/-2.92 D (range, 29.43-47.68 D). In the presence of glare, mean BCVA decreased to 20/100+/-20/100 (range, counting fingers-20/32). Potential acuity meter (PAM) readings were significantly (P<0.05) higher than BCVA. Mean PAM reading was 20/25+/-20/100 (range, 20/100-20/16). Seven patients (11 eyes) were extremely satisfied with the operative result more than 10 years after the operation, whereas four patients (four eyes) were not satisfied at all.

CONCLUSIONS

Epikeratophakia for the correction of myopia improved UCVA significantly, but BCVA decreased. The removal of the lenticules in patients who were not satisfied with their visual acuity was uncomplicated, and acceptable vision could be achieved with either contact lenses or intraocular lens implantation.

Corneal Sensitivity 10 Years After Epikeratoplasty

PURPOSE

To assess corneal sensitivity in patients 10 or more years after epikeratoplasty for myopia, aphakia, hyperopia, and keratoconus.

METHODS

A total of 45 eyes of 33 patients (age range at examination 33 to 55 yr) were included in the study. Corneal sensitivity thresholds using an electromagnetic aesthesiometer (Draeger) were measured at various locations on the lenticule and the recipient cornea. Measurements were evaluated regarding the corrective purpose, surgical technique, age, and gender of the patients and the area of measurements.

RESULTS

The mean corneal sensitivity threshold in the center of the epikeratoplasty lenticule was significantly lower than on the peripheral recipient cornea (320.0 +/- 365.1 x 10(-5) N versus 0.1 +/- 0.5 x 10(-5) N). Corneal sensitivity at the 3 and 9 o'clock positions was significantly higher compared to the values at the 6 and 12 o'clock positions on the lenticule. No correlations of these values with age, gender, type, and primary indications for the surgery were observed.

CONCLUSIONS

These results indicate a relative hypesthesia of the epikeratoplasty lenticule as compared to the peripheral host cornea, even 10 years after surgery. In our patients no clinically significant changes were observed that could be attributed to the reduced sensitivity over this follow-up period.

Influence of dorzolamide on corneal thickness, endothelial cell count and corneal sensibility

PURPOSE

Dorzolamide (Trusopt) is the first topical carbonic anhydrase inhibitor (CAI) that is in clinical use in glaucoma therapy. It is known that CAI have a negative effect on corneal endothelial pumpfunction and therefore on the whole corneal physiology.

METHODS

20 patients with open angle glaucoma or ocular hypertension and an elevated intraocular pressure (IOP) over 21 mmHg and without prior oral CAI-treatment were included in this study. Trusopt was administered t.i.d. as monotherapy and b.i.d. in combination with other topical antiglaucoma drugs. Corneal ultrasound pachymetry, corneal endothelial cell count and aesthesiometry were performed prestudy and on days 1, 8, 15, 30, 60 and 90.

RESULTS AND CONCLUSIONS

Mean corneal thickness was slightly increased on day one (statistically non-significant) and returned to baseline measurements at the following visits, no changes in endothelial cell count and corneal anesthesia were found. Topical dorzolamide is not associated with clinically meaningful changes of the cornea.