40 research outputs found
Method for machining holes in composite materials
A method for boring well defined holes in a composite material such as graphite/epoxy is discussed. A slurry of silicon carbide powder and water is projected onto a work area of the composite material in which a hole is to be bored with a conventional drill bit. The silicon carbide powder and water slurry allow the drill bit, while experiencing only normal wear, to bore smooth, cylindrical holes in the composite material
Loss from treatment for drug resistant tuberculosis: risk factors and patient outcomes in a community-based program in Khayelitsha, South Africa
BACKGROUND: A community based drug resistant tuberculosis (DR-TB) program has been incrementally implemented in Khayelitsha, a high HIV and TB burden community in South Africa. We investigated loss from treatment (LFT), and post treatment outcomes of DR-TB patients in this setting. METHODOLOGY: LFT, defined as interruption of treatment for ≥2 consecutive months was assessed among patients initiating DR-TB treatment for the first time between January 2009 and July 2011. Patients were traced through routine data sources to identify those who subsequently restarted treatment and those who died. Additional information on patient status and survival after LTF was obtained from community DR-TB counselors and from the national death registry. Post treatment outcomes were observed until July 2013. RESULTS: Among 452 patients initiating treatment for the first time within the given period, 30% (136) were LFT, with 67% retention at 18 months. Treatment was restarted in 27 (20%) patients, with additional resistance recorded in 2/25 (8%), excluding two with presumed DR-TB. Overall, 34 (25%) patients died, including 11 who restarted treatment. Males and those in the age category 15-25 years had a greater hazard of LFT; HR 1.93 (95% CI 1.35-2.75), and 2.43 (95% CI 1.52-3.88) respectively. Older age (>35 years) was associated with a greater hazard of death; HR 3.74 (1.13- 12.37) post treatment. Overall two-year survival was 62%. It was lower (45%) in older patients, and was 92% among those who received >12 months treatment. CONCLUSION: LFT was high, occurred throughout the treatment period and was particularly high among males and those aged 15-25 years. Overall long term survival was poor. High rates of LFT should however not preclude scale up of community based care given its impact in increasing access to treatment. Further research is needed to support retention of DR-TB patients on treatment, even within community based treatment programs
Implementing a Substance-Use Screening and Intervention Program for People Living with Rifampicin-Resistant Tuberculosis: Pragmatic Experience from Khayelitsha, South Africa
Substance use (SU) is associated with poor rifampicin-resistant tuberculosis (RR-TB) treatment outcomes. In 2017, a SBIRT (SU screening-brief intervention-referral to treatment) was integrated into routine RR-TB care in Khayelitsha, South Africa. This was a retrospective study of persons with RR-TB who were screened for SU between 1 July 2018 and 30 September 2020 using the ASSIST (Alcohol, Smoking and Substance Involvement Screening Test). Here we describe outcomes from this program. Persons scoring moderate/high risk received a brief intervention and referral to treatment. Overall, 333 persons were initiated on RR-TB treatment; 38% (n = 128) were screened for SU. Of those, 88% (n = 113/128) reported SU; 65% (n = 83/128) had moderate/high risk SU. Eighty percent (n = 103/128) reported alcohol use, of whom 52% (n = 54/103) reported moderate/high risk alcohol use. Seventy-seven persons were screened for SU within ≤2 months of RR-TB treatment initiation, of whom 69%, 12%, and 12% had outcomes of treatment success, loss to follow-up and death, respectively. Outcomes did not differ between persons with no/low risk and moderate/high risk SU or based on the receipt of naltrexone (p > 0.05). SU was common among persons with RR-TB; there is a need for interventions to address this co-morbidity as part of “person-centered care”. Integrated, holistic care is needed at the community level to address unique challenges of persons with RR-TB and SU
Time to ART initiation among patients treated for rifampicin-resistant tuberculosis in Khayelitsha, South Africa: impact on mortality and treatment success
Setting Khayelitsha, South Africa, with high burdens of rifampicin-resistant tuberculosis (RR-TB) and HIV co-infection. Objective To describe time to antiretroviral treatment (ART) initiation among HIV-infected RR-TB patients initiating RR-TB treatment and to assess the association between time to ART initiation and treatment outcomes. Design A retrospective cohort study of patients with RR-TB and HIV co-infection not on ART at RR-TB treatment initiation. RESULTS: Of the 696 RR-TB and HIV-infected patients initiated on RR-TB treatment between 2009 and 2013, 303 (44%) were not on ART when RR-TB treatment was initiated. The median CD4 cell count was 126 cells/mm 3 . Overall 257 (85%) patients started ART during RR-TB treatment, 33 (11%) within 2 weeks, 152 (50%) between 2-8 weeks and 72 (24%) after 8 weeks. Of the 46 (15%) who never started ART, 10 (21%) died or stopped RR-TB treatment within 4 weeks and 16 (37%) had at least 4 months of RR-TB treatment. Treatment success and mortality during treatment did not vary by time to ART initiation: treatment success was 41%, 43%, and 50% among patients who started ART within 2 weeks, between 2-8 weeks, and after 8 weeks (p = 0.62), while mortality was 21%, 13% and 15% respectively (p = 0.57). Mortality was associated with never receiving ART (adjusted hazard ratio (aHR) 6.0, CI 2.1-18.1), CD4 count ≤100 (aHR 2.1, CI 1.0-4.5), and multidrug-resistant tuberculosis (MDR-TB) with second-line resistance (aHR 2.5, CI 1.1-5.4). CONCLUSIONS: Despite wide variation in time to ART initiation among RR-TB patients, no differences in mortality or treatment success were observed. However, a significant proportion of patients did not initiate ART despite receiving >4 months of RR-TB treatment. Programmatic priorities should focus on ensuring all patients with RR-TB/HIV co-infection initiate ART regardless of CD4 count, with special attention for patients with CD4 counts ≤ 100 to initiate ART as soon as possible after RR-TB treatment initiation
Founder Mutation in RSPH4A Identified in Patients of Hispanic Descent with Primary Ciliary Dyskinesia
Primary ciliary dyskinesia (PCD) is a rare, autosomal recessive, genetically heterogeneous disorder characterized by ciliary dysfunction resulting in chronic oto-sino-pulmonary disease, respiratory distress in term neonates, laterality (situs) defects, and bronchiectasis. Diagnosis has traditionally relied on ciliary ultrastructural abnormalities seen by electron microscopy. Mutations in radial spoke head proteins occur in PCD patients with central apparatus defects. Advances in genetic testing have been crucial in addressing the diagnostic challenge. Here, we describe a novel splice-site mutation (c.921+3_6delAAGT) in RSPH4A, which leads to a premature translation termination signal in nine subjects with PCD (seven families). Loss-of-function was confirmed with quantitative ciliary ultrastructural analysis, measurement of ciliary beat frequency and waveform, and transcript analysis. All nine individuals carrying c.921+3_6delAAGT splice-site mutation in RSPH4A were Hispanic with ancestry tracing to Puerto Rico. This mutation is a founder mutation and a common cause of PCD without situs abnormalities in patients of Puerto Rican descent
Genetic mechanisms of critical illness in COVID-19.
Host-mediated lung inflammation is present1, and drives mortality2, in the critical illness caused by coronavirus disease 2019 (COVID-19). Host genetic variants associated with critical illness may identify mechanistic targets for therapeutic development3. Here we report the results of the GenOMICC (Genetics Of Mortality In Critical Care) genome-wide association study in 2,244 critically ill patients with COVID-19 from 208 UK intensive care units. We have identified and replicated the following new genome-wide significant associations: on chromosome 12q24.13 (rs10735079, P = 1.65 × 10-8) in a gene cluster that encodes antiviral restriction enzyme activators (OAS1, OAS2 and OAS3); on chromosome 19p13.2 (rs74956615, P = 2.3 × 10-8) near the gene that encodes tyrosine kinase 2 (TYK2); on chromosome 19p13.3 (rs2109069, P = 3.98 × 10-12) within the gene that encodes dipeptidyl peptidase 9 (DPP9); and on chromosome 21q22.1 (rs2236757, P = 4.99 × 10-8) in the interferon receptor gene IFNAR2. We identified potential targets for repurposing of licensed medications: using Mendelian randomization, we found evidence that low expression of IFNAR2, or high expression of TYK2, are associated with life-threatening disease; and transcriptome-wide association in lung tissue revealed that high expression of the monocyte-macrophage chemotactic receptor CCR2 is associated with severe COVID-19. Our results identify robust genetic signals relating to key host antiviral defence mechanisms and mediators of inflammatory organ damage in COVID-19. Both mechanisms may be amenable to targeted treatment with existing drugs. However, large-scale randomized clinical trials will be essential before any change to clinical practice
E: Rheumatoid forefoot deformity: a comparison study of 2 functional methods of reconstruction
The forefoot is an important area of morbidity in rheumatoid arthritis (RA). Initial manifestation of RA occurs in the foot in 16% of patients 1 ; 80-100% patients with a 10-year history have symptomatic forefoot problems 2-6 ; 25-40% of all surgical procedures are done on the foo
The postoperative COFAS end-stage ankle arthritis classification system: interobserver and intraobserver reliability
End-stage ankle arthritis is operatively treated with numerous designs of total ankle replacement and different techniques for ankle fusion. For superior comparison of these procedures, outcome research requires a classification system to stratify patients appropriately. A postoperative 4-type classification system was designed by 6 fellowship-trained foot and ankle surgeons. Four surgeons reviewed blinded patient profiles and radiographs on 2 occasions to determine the interobserver and intraobserver reliability of the classification. Excellent interobserver reliability (κ = .89) and intraobserver reproducibility (κ = .87) were demonstrated for the postoperative classification system. In conclusion, the postoperative Canadian Orthopaedic Foot and Ankle Society (COFAS) end-stage ankle arthritis classification system appears to be a valid tool to evaluate the outcome of patients operated for end-stage ankle arthritis