Timeliness metrics for screening and preventing TB in household contacts of pulmonary TB patients in Kenya.

BACKGROUND: The study assessed whether a "7-1-7" timeliness metric for screening and TB preventive therapy (TPT) could be implemented for household contacts (HHCs) of index patients with bacteriologically confirmed pulmonary TB under routine programmatic settings in Kenya. METHODS: A longitudinal cohort study conducted among index patients and their HHCs in 12 health facilities, Kiambu County, Kenya. RESULTS: Between January and June 2023, 95% of 508 index patients had their HHCs line-listed within 7 days of initiating anti-TB treatment ("First 7"). In 68% of 1,115 HHCs, screening outcomes were ascertained within 1 day of line-listing ("Next 1"). In 65% of 1,105 HHCs eligible for further evaluation, anti-TB treatment, TPT or a decision for no drugs was made within 7 days of screening ("Second 7"). Altogether, 62% of screened HHCs started TPT during the "7-1-7" period compared with 58% in a historical cohort. Main barriers to TPT uptake were HHCs not consulting clinicians, HHCs being unwilling to initiate TPT and drug shortages. Healthcare workers felt that a timeliness metric was valuable for streamlining HHC management and proposed "3-5-7" as a workable alternative. CONCLUSIONS: The national TB programme must generate awareness about TPT, ensure uninterrupted drug supplies and assess whether the "3-5-7" metric can be operationalised.

CONTEXTE: L'étude a évalué si une mesure de rapidité "7-1-7" pour le dépistage et le traitement préventif de la TB (TPT) pouvait être mise en œuvre pour les contacts familiaux des patients index atteints de TB pulmonaire confirmée bactériologiquement dans le cadre d'un programme de routine au Kenya. MÉTHODES: Étude de cohorte longitudinale menée auprès de patients index et de leurs contacts familiaux dans 12 établissements de santé du comté de Kiambu, au Kenya. RÉSULTATS: Entre janvier et juin 2023, 95% des 508 patients index ont eu leur centre de santé inscrit sur la liste dans les 7 jours suivant le début du traitement antituberculeux (« First 7 ¼ ). Dans 68% des 1 115 centres de santé, les résultats du dépistage ont été vérifiés dans le jour suivant l'inscription sur la liste (« Next 1 ¼). Dans 65% des 1 105 centres de santé éligibles pour une évaluation plus approfondie, le traitement antituberculeux, le TPT ou la décision de ne pas prendre de médicaments a été prise dans les 7 jours suivant le dépistage (« Second 7 ¼). Au total, 62% des patients dépistés ont commencé un traitement antituberculeux au cours de la période « 7-1-7 ¼, contre 58% dans une cohorte historique. Les principaux obstacles à l'adoption du TPT étaient les suivants : les centres de santé ne consultaient pas les cliniciens, les centres de santé n'étaient pas disposés à commencer le TPT et les pénuries de médicaments. Les professionnels de la santé ont estimé qu'une mesure de la rapidité d'exécution était utile pour rationaliser la gestion des centres de santé et ont proposé le « 3-5-7 ¼ comme solution de rechange viable. CONCLUSION: Le programme national de lutte contre la TB doit sensibiliser au TPT, garantir un approvisionnement ininterrompu en médicaments et évaluer si la mesure « 3-5-7 ¼ peut être mise en œuvre.

Using timeliness metrics for household contact tracing and TB preventive therapy in the private sector, India.

Although screening of household contacts (HHCs) of TB patients and provision of TB preventive therapy (TPT) is a key intervention to end the TB epidemic, their implementation globally is dismal. We assessed whether introducing a '7-1-7' timeliness metric was workable for implementing HHC screening among index patients with pulmonary TB diagnosed by private providers in Chennai, India, between November 2022 and March 2023.This was an explanatory mixed-methods study (quantitative-cohort and qualitative-descriptive).There were 263 index patients with 556 HHCs. In 90% of index patients, HHCs were line-listed within 7 days of anti-TB treatment initiation. Screening outcomes were ascertained in 48% of HHCs within 1 day of line-listing. Start of anti-TB treatment, TPT or a decision to receive neither was achieved in 57% of HHC within 7 days of screening. Overall, 24% of screened HHCs in the '7-1-7' period started TPT compared with 16% in a historical control (P < 0.01). Barriers to achieving '7-1-7' included HHC reluctance for evaluation or TPT, refusal of private providers to prescribe TPT and reliance on facility-based screening of HHCs instead of home visits by health workers for screening.Introduction of a timeliness metric is a workable intervention that adds structure to HHC screening and timely management..

Adenovirus mediated expression of therapeutic plasma levels of human factor IX in mice.

Gene therapy strategies designed to combat haemophilia B, caused by defects in clotting factor IX, have so far concentrated on ex vivo approaches. We have now evaluated adenoviral vector-mediated expression of human factor IX in vivo. Injection of the vector Av1H9B, which encodes human factor IX cDNA, into the tail veins of mice resulted in efficient liver transduction and plasma levels of human factor IX that would be therapeutic for haemophilia B patients. However, levels slowly declined to baseline by nine weeks and were not re-established by a second vector injection. These results address both the advantages and obstacles to the use of adenoviral vectors for treatment of haemophilia B.

Evidence for gene transfer and expression of factor IX in haemophilia B patients treated with an AAV vector.

Pre-clinical studies in mice and haemophilic dogs have shown that introduction of an adeno-associated viral (AAV) vector encoding blood coagulation factor IX (FIX) into skeletal muscle results in sustained expression of F.IX at levels sufficient to correct the haemophilic phenotype. On the basis of these data and additional pre-clinical studies demonstrating an absence of vector-related toxicity, we initiated a clinical study of intramuscular injection of an AAV vector expressing human F.IX in adults with severe haemophilia B. The study has a dose-escalation design, and all patients have now been enrolled in the initial dose cohort (2 x 10(11) vg/kg). Assessment in the first three patients of safety and gene transfer and expression show no evidence of germline transmission of vector sequences or formation of inhibitory antibodies against F.IX. We found that the vector sequences are present in muscle by PCR and Southern-blot analyses of muscle biopsies and we demonstrated expression of F.IX by immunohistochemistry. We observed modest changes in clinical endpoints including circulating levels of F.IX and frequency of FIX protein infusion. The evidence of gene expression at low doses of vector suggests that dose calculations based on animal data may have overestimated the amount of vector required to achieve therapeutic levels in humans, and that the approach offers the possibility of converting severe haemophilia B to a milder form of the disease.

Cell proliferation and expression of the transferrin receptor gene: promoter sequence homologies and protein interactions.

A 365-bp fragment from the 5' region of the human transferrin receptor gene has been subcloned and sequenced. This fragment contains 115 bp of flanking sequence, the first exon, and a portion of the first intron. It contains a TATA box, several GC-rich regions, and is able to efficiently promote expression of the bacterial CAT gene in mouse 3T3 cells. Sequence comparisons demonstrate that this DNA segment has homology to the promoter regions of the human dihydrofolate reductase gene and the mouse interleukin 3 gene, as well as to a monkey DNA sequence that has homology to the SV40 origin and promotes expression of an unidentified gene product. Several high molecular mass proteins that interact with the transferrin receptor gene promoter have been identified. The activity of these proteins is transiently increased in 3T3 cells that have been stimulated by serum addition. This increase precedes a rise in transferrin receptor mRNA levels in the cytoplasm, which in turn precedes entry of the cells into S phase. DNase I footprinting of the transferrin receptor promoter reveals several protein binding sites. Two of the sites are within the conserved GC-rich region of the promoter. One of these binding sites probably interacts with Spl, while the second interacts with an uncharacterized protein.

Evidence for a grammar-specific deficit in children.

BACKGROUND: Specific language impairment (SLI) is a disorder in which language acquisition is impaired in an otherwise normally developing child. SLI affects around 7% of children. The existence of a purely grammatical form of SLI has become extremely controversial because it points to the existence and innateness of a putative grammatical subsystem in the brain. Some researchers dispute the existence of a purely grammatical form of SLI. They hypothesise that SLI in children is caused by deficits in auditory and/or general cognitive processing, or social factors. There are also claims that the cognitive abilities of people with SLI have not yet been sufficiently characterised to substantiate the existence of SLI in a pure grammatical form. RESULTS: We present a case study of a boy, known as AZ, with SLI. To investigate the claim for a primary grammatical impairment, we distinguish between grammatical abilities, non-grammatical language abilities and non-verbal cognitive abilities. We investigated AZ's abilities in each of these areas. AZ performed normally on auditory and cognitive tasks, yet exhibited severe grammatical impairments. This is evidence for a developmental grammatical deficit that cannot be explained as a by-product of retardation or auditory difficulties. CONCLUSIONS: The case of AZ provides evidence supporting the existence of a genetically determined, specialised mechanism that is necessary for the normal development of human language.

Transcriptional regulation by iron of the gene for the transferrin receptor.

Treatment of K562 cells with desferrioxamine, a permeable iron chelator, led to an increase in the number of transferrin receptors. Increasing intracellular iron levels by treatment of cells with either human diferric transferrin or hemin lowered the level of the transferrin receptors. By using a cDNA clone of the human transferrin receptor, we showed that the changes in the levels of the receptor by iron were accompanied by alterations in the levels of the mRNA for the receptor. The rapidity of these changes indicated that the mRNA had a very short half-life. By using an in vitro transcriptional assay with isolated nuclei, we obtained evidence that this regulation occurred at the transcriptional level.

Nonhematopoietic neoplasms in cats.

In a study of 3,145 feline necropsies conducted for 11 years by the pathology department of The Animal Medical Center, 289 tumors of nonhematopoietic origin were found in 264 cats. Malignant and epithelial tumors were more common than benign or mesenchymal tumors in all ages and breeds, and in both sexes. They were also more common in female cats than in males, even after mammary neoplasms were excluded. Analysis of groups of tumors according to their tissue of origin indicated some sex and breed dispositions not observed before. Pulmonary carcinomas and osteosarcomas were more frequent in domestic short haired cats than in other breeds, whereas intestinal carcinomas occurred more often in Siamese cats. Female predominated in pulmonary carcinomas, hemangiosarcomas, osteosarcomas, and squamous cell carcinomas, but males outnumbered the females in intestinal carcinomas.

Biology of feline leukemia virus in the natural environment.

The feline leukemia virus (FeLV) was discovered in 1964 in a cluster of cats with lymphosarcoma. The observed clustering of cases of feline lymphosarcoma suggested that FeLV was an infectious agent for cats. The development of a simple immunofluorescent test for FeLV permitted a seroepidemiological study to be undertaken on the distribution of the virus in cats living in their natural environment. Over 2000 cats were tested, and the results showed conclusively that FeLV is an infectious agent for cats. This finding has now been independently confirmed using three different test procedures. After the infectious nature of FeLV was discovered, a simple FeLV test and removal program was devised to control the spread of the virus in the natural environment. The spread of FeLV was controlled in 45 households by removing the FeLV-infected cats, while in 25 households, where the infected cats were left in contact with the uninfected cats, 12% of the uninfected cats became infected. The ultimate control of FeLV awaits the development of an effective FeLV vaccine, which now seems feasible since we have already experimentally immunized some cats with attenuated FeLV. Although FeLV is infectious for cats there is no evidence that FeLV can infect humans.

Quantitative Evaluation of Medial Temporal Lobe Morphology in Children with Febrile Status Epilepticus: Results of the FEBSTAT Study.

BACKGROUND AND PURPOSE: The pathogenesis of febrile status epilepticus is poorly understood, but prior studies have suggested an association with temporal lobe abnormalities, including hippocampal malrotation. We used a quantitative morphometric method to assess the association between temporal lobe morphology and febrile status epilepticus. MATERIALS AND METHODS: Brain MR imaging was performed in children presenting with febrile status epilepticus and control subjects as part of the Consequences of Prolonged Febrile Seizures in Childhood study. Medial temporal lobe morphologic parameters were measured manually, including the distance of the hippocampus from the midline, hippocampal height:width ratio, hippocampal angle, collateral sulcus angle, and width of the temporal horn. RESULTS: Temporal lobe morphologic parameters were correlated with the presence of visual hippocampal malrotation; the strongest association was with left temporal horn width (P < .001; adjusted OR, 10.59). Multiple morphologic parameters correlated with febrile status epilepticus, encompassing both the right and left sides. This association was statistically strongest in the right temporal lobe, whereas hippocampal malrotation was almost exclusively left-sided in this cohort. The association between temporal lobe measurements and febrile status epilepticus persisted when the analysis was restricted to cases with visually normal imaging findings without hippocampal malrotation or other visually apparent abnormalities. CONCLUSIONS: Several component morphologic features of hippocampal malrotation are independently associated with febrile status epilepticus, even when complete hippocampal malrotation is absent. Unexpectedly, this association predominantly involves the right temporal lobe. These findings suggest that a spectrum of bilateral temporal lobe anomalies are associated with febrile status epilepticus in children. Hippocampal malrotation may represent a visually apparent subset of this spectrum.

Expression of tissue inhibitor of matrix metalloproteinases 1 by use of an adenoviral vector inhibits smooth muscle cell migration and reduces neointimal hyperplasia in the rat model of vascular balloon injury.

BACKGROUND: Cell migration is a major contributor to injury-induced neointimal hyperplasia and depends on alteration of the proteolytic balance within the arterial wall toward matrix breakdown. This is partly mediated by the matrix metalloproteinases (MMPs) and their natural inhibitors, the tissue inhibitors of metalloproteinases (TIMPs). METHODS AND RESULTS: An increase in expression of biologically active and immunoreactive TIMP-1 was seen in vitro after infection of rat smooth muscle cells (SMCs) with Av1.TIMP1 (an adenoviral vector containing the human TIMP1 cDNA). Infection of rat SMCs with Av1.TIMP1 reduced migration in vitro by 27% compared with control virus-infected cells (37.6+/-4.34 versus 51+/-5.01 cells per high-power field, P<0.05). The adenoviral vector was delivered to the injured rat carotid artery, and 4 days later, immunoreactive protein was identified and migration of SMCs reduced by 60% (5.2+/-0. 5 versus 12.8+/-1.5 cells per section, P<0.05, n=5). Neointimal area 14 days after injury showed a 30% reduction in the animals receiving the Av1.TIMP1 virus compared with controls (0.09+/-0.01 versus 0. 14+/-0.01 mm2, P=0.02, n=14). CONCLUSIONS: The response to arterial balloon injury involves MMP-dependent SMC migration and can be attenuated in vivo by the transmural expression of TIMP-1 by adenoviral gene transfer.

Sequence conservation around the 5' ends of the larval serum protein 1 genes of Drosophila melanogaster.

We have determined the nucleotide sequence at the 5' ends of the genes for the alpha, beta and gamma polypeptides of larval serum protein 1 (LSP1) of Drosophila melanogaster. In their upstream regions, the three genes share homology around the TATA boxes. There is also a homologous region of about 20 nucleotides at positions 200, 216 and 377 upstream from the alpha, beta and gamma genes, respectively. Another 18-nucleotide homology occurs between a sequence 111 nucleotides upstream from the alpha gene and 130 nucleotides upstream of the beta gene. This contains a seven-nucleotide match with a sequence 180 nucleotides upstream from the gamma gene. The sequences corresponding to the 5' non-translated regions of the RNA show two regions of strong homology: one being within the first 20 nucleotides at the very 5' end of the RNA, and the other being between nucleotides 27 and 52 of the three transcripts. The first AUG codon to precede a long open reading frame is found at nucleotides 89, 86 and 83 downstream from the 5' end of the alpha, beta and gamma RNAs, respectively. An extremely conserved nucleotide sequence with an exact homology of 66 nucleotides between the alpha and beta genes, and sharing 27 nucleotides with the gamma gene, is contained within this long open reading frame in the first exon. Conceptual translation of the long open reading frame shows that the hydrophobic nature of the first 20 amino acids of the three polypeptides has been conserved whereas the exact sequence has not. This suggests that the N termini contain signal sequences required for secretion of the protein into the haemolymph. The three genes have intervening sequences ranging from 65 to 68 nucleotides in length at comparable locations close to the 5' end of the genes.

Preliminary X-ray crystallographic analysis of intercellular adhesion molecule-1.

Crystals of the two amino-terminal domains of intercellular adhesion molecule-1, the receptor for the major group of human rhinovirus serotypes, diffract to 3.0 A resolution. The crystals are trigonal in space group P3(1)21 or P3(2)21 with cell dimensions of a = b = 55.7 A, c = 166.3 A, with probably six molecules per unit cell.

High-level tissue-specific expression of functional human factor VIII in mice.

Hemophilia A results from subnormal levels of blood coagulation factor VIII (FVIII) and is an attractive target for gene therapy. However, progress has been impeded by features of FVIII biology such as low mRNA accumulation and the instability of the protein. We have shown previously that a FVIII adenoviral vector, Av1ALH81, allowed high-level expression of human FVIII in mice sustained for several weeks. Here, we have generated a second FVIII adenoviral vector, Av1ALAPH81, in which an intron was introduced into the FVIII expression cassette. Administration of Av1ALAPH81 to mice resulted in significantly increased FVIII plasma levels, 1,046 +/- 163 ng/ml compared to 307 +/- 93 ng/ml of FVIII detected in mice that received Av1ALH81. Normal FVIII levels in humans are 100-200 ng/ml and therapeutic levels are as low as 10 ng/ml. Therapeutic levels are defined as the amount of FVIII necessary to convert severe hemophilia to a moderate or mild hemophiliac condition. The increased potency of the second FVIII adenoviral vector allowed the administration of significantly lower, less toxic vector doses, while retaining the potential for high FVIII expression. Furthermore, we demonstrate that adenoviral-mediated expression of human FVIII can be limited to the liver by inclusion of a liver-specific promoter, thereby achieving the first step in regulated expression of human FVIII in vivo.

In vivo gene delivery and expression of physiological levels of functional human factor VIII in mice.

Hemophilia A is caused by blood coagulation factor VIII (FVIII) deficiency and is an attractive target for gene therapy. However, features of FVIII physiology, such as the instability of the mRNA and protein, have provided obstacles to the design of a feasible strategy for the transfer and expression of the human FVIII gene in vivo. We have constructed a recombinant adenoviral vector, Av1ALH81, that contains the human FVIII cDNA from which the B-domain has been deleted (BDD FVIII) and extensively characterized this vector in vitro and in vivo. In vitro, HepG2, human hepatoma cells, transduced with Av1ALH81 secreted high levels of biologically active human BDD FVIII measured by the Coatest bioassay (> 2,400 mU per 10(6) cells per 24 hr). Administration of Av1ALH81 to mice, via tail vein, resulted in expression of human BDD FVIII in the mouse plasma at levels averaging 307 +/- 93 ng/ml 1 week post-injection, measured by a sensitive human FVIII-specific ELISA. Normal FVIII levels in humans are 100-200 ng/ml, and therapeutic levels are as low as 10 ng/ml. Purification of the human FVIII from the mouse plasma, and subsequent Coatest analysis, revealed that the human FVIII produced in the mice was biologically active. In addition, the duration of FVIII expression in vivo was followed, and high-level FVIII expression was sustained over a period of several weeks. The finding that an adenoviral vector can mediate high-level expression of human FVIII in an animal model provides the basis for the development of gene therapy for hemophilia A.

Molecular cloning of receptor genes by transfection.

We have described a transfection method for the isolation of surface antigen genes which requires no mRNA or protein purification. Application of this technique results in the recovery of the entire gene in a single step since selection for expression of genomic DNA forms the basis of the procedure. Based on our results with the transferrin receptor gene and other systems, it is evident that large transcription units can be transferred and expressed in mouse L-cells. This size consideration represents a major advantage over the use of cosmid shuttle vectors for genomic DNA expression. In the case of genes which code for very long mRNAs this method may also have advantages over cDNA expression systems. Although we have described methods for FACS isolation of transfectants based on the binding of species specific antibodies to surface antigens, other methods of identifying transfected cells could be employed. For example, in combination with an appropriate assay, sib selection of recipient cells could be used to identify genes encoding secreted products. Ligand binding assays could be used for receptors which are not expressed on the host cell. Finally, the development of cDNA expression vectors which produce membrane-associated products would extend this methodology to genes not normally expressed at the cell surface.

Crystallographic and cryo EM analysis of virion-receptor interactions.

Cryoelectron microscopy has been used to determine the first structure of a virus when complexed with its glycoprotein cellular receptor. Human rhinovirus 16 (HRV16) complexed with the two amino-terminal, immunoglobulin-like domains of the intercellular adhesion molecule-1 (ICAM-1) shows that ICAM-1 binds into the 12 A deep "canyon" on the surface of the virus. This is consistent with the prediction that the viral receptor attachment site lies in a cavity inaccessible to the host's antibodies. The atomic structures of HRV14 and CD4, homologous to HRV16 and ICAM-1, showed excellent correspondence with observed density, thus establishing the virus-receptor interactions.

Primary surgery for hyperparathyroidism: the lateral approach after preoperative ultrasonographic localization.

Increasing experience and improving equipment has made ultrasonography the localizing test of choice before neck exploration for hyperparathyroidism is carried out. A study of 16 patients who were examined with ultrasonography before exploration showed that the sensitivity for finding enlarged parathyroid glands was 80 percent, the specificity 95 percent, and the diagnostic accuracy 91 percent. Our operative technique was altered from the classic midline exploration, with bilateral division of the strap muscles, to a lateral approach on the basis of our experience with a high-risk patient who had undergone unilateral exploration under local anesthesia after successful ultrasonographic localization. We found the results with the lateral approach to be equivalent to the results using the midline approach. The lateral approach appeared to be more direct, efficient, and less traumatic than the classic midline approach. This technique is well suited for parathyroid exploration with local anesthesia in high-risk patients who have multiple system failure.