The management of proximal rectus femoris avulsion injuries.

Injuries to the quadriceps muscle group are commonly seen in sporting activities that involve repetitive kicking and high-speed sprinting, including football (soccer), rugby and athletics.The proximal rectus femoris is prone to avulsion injuries as rapid eccentric muscle contraction leads to asynchronous muscle activation and different force vectors through the straight and reflected heads.Risk factors for injury include previous rectus femoris muscle or hamstring injury, reduced flexibility of the quadriceps complex, injury to the dominant leg, and dry field playing conditions.Magnetic resonance imaging (MRI) is the preferred imaging modality as it enables the site of injury to be accurately located, concurrent injuries to be identified, preoperative grading of the injury, and aids surgical planning.Non-operative management is associated with highly variable periods of convalescence, poor return to preinjury level of function and high risk of injury recurrence.Operative treatment of proximal rectus femoris avulsion injuries with surgical repair or surgical tenodesis enables return to preinjury level of sporting activity and high functional outcomes.Surgical tenodesis of proximal rectus femoris avulsion injuries may offer an avenue for further reducing recurrence rates compared to direct suture anchor repair of these injuries. Cite this article: EFORT Open Rev 2020;5:828-834. DOI: 10.1302/2058-5241.5.200055.

Reverse shoulder replacement: a day-case procedure.

BACKGROUND AND HYPOTHESIS: Reverse shoulder arthroplasty (RSA) is an increasingly popular treatment modality for glenohumeral joint arthritis in association with rotator cuff arthropathy. A prolonged hospital stay following joint arthroplasty risks increased complications for patients plus financial implications for institutions. We hypothesized that RSA could be safely and effectively carried out as an outpatient procedure with reduced risks to patients and institutional costs. METHODS: Patients attending our institution for RSA during March 2015 to August 2018 were reviewed preoperatively for consideration for RSA as an outpatient procedure. The inclusion criteria were arthritis of the shoulder having failed conservative management, age older than 50 years, and intact deltoid muscle function. Patients were excluded if they underwent RSA for trauma or for revision following previous total shoulder replacement or hemiarthroplasty. Overall health, social circumstances, and individual wishes were considered. RESULTS: A total of 21 patients underwent RSA as an outpatient procedure. The mean age was 74 years (range, 59-84 years). There were 8 male and 13 female patients. No overnight stays were required in patients in whom outpatient surgery was planned. The Oxford Shoulder Score increased from a mean of 16 (range, 4-30) preoperatively to a mean of 31 (range, 7-35) at 6 months postoperatively; it was a mean of 36 (range, 7-48) at 12 months postoperatively. Of the patients, 88% were "very satisfied" or "satisfied" with the service and 81% would undergo the surgical procedure again as a day-case procedure. CONCLUSION: RSA as an outpatient procedure can be carried out effectively with high patient satisfaction rates in carefully selected patients.

'Goose bumps' as presenting feature of intraventricular glioblastoma multiforme.

'Goose-bumps' seizures are rare manifestations of epilepsy. They are rarely reported by patients and can be easily dismissed by clinicians. Clinically, it carries some diagnostic localising value especially with unilateral onset. In this report, we present a case of intraventricular glioblastoma multiforme with ipsilateral goose bumps and review the literature.

A radiological sign in chronic collateral ligament injuries of the thumb metacarpophalangeal joint.

BACKGROUND: Differentiating chronic from acute injuries of the collateral ligament of the metacarpophalangeal joint (MCPJ) of the thumb can be difficult in the absence of a conclusive history and examination. We aimed to establish the presence of a radiological sign in patients with a chronic injury and the reliability of the sign in differentiating chronic from acute ligament injury. METHODS: Consecutive patients undergoing surgical treatment for chronic (n = 14) or acute (n = 8) ligament injury of the MCPJ of the thumb were identified retrospectively. Six upper limb orthopedic surgeons and four musculoskeletal radiologists were recruited from three regional centers. Observers judged the presence or absence of the sign, an exostosis at the level of the neck of the thumb metacarpal, on radiographs presented on a computer program. The radiographs were then observed in a different random order. The sensitivity, specificity, positive predictive value (PPV), and negative predictive values (NPV) of the radiological sign were evaluated for each observer and the intra- and interobserver error was calculated. RESULTS: The mean observer specificity and sensitivity for the sign were 84 and 54 %, respectively. The PPV and NPV were 89 and 52 %, respectively. The kappa statistic for intraobserver error was 0.69 and interobserver error 0.34. CONCLUSIONS: A radiological sign associated with chronic collateral ligament injuries of the MCPJ of the thumb is established. The presence of the sign can increase the confidence of the clinician in differentiating chronic from acute collateral ligament injuries, when history and examination are inconclusive in this respect.

Evaluation of the CaMAL2 promoter for regulated expression of genes in Candida albicans.

An expression vector (CIp10-MAL2p) for use in Candida albicans has been constructed in which a gene of interest can be placed under the control of the CaMAL2 maltase promoter and stably integrated at the CaRP10 locus. Using this vector to express the Candida URA3 gene from the CaMAL2 promoter, we have demonstrated tight regulation of CaURA3 expression by carbon source. Thus under conditions when the CaMAL2 promoter is not induced, expression of Candida URA3 was unable either to complement a C. albicans ura3 mutation or to confer sensitivity to 5-fluoroorotic acid, a compound which is highly toxic to URA3 strains. Since Candida albicans is an obligate diploid organism, analysis of gene function requires manipulation of both copies of any gene of interest. Our expression vector provides a strategy by which the remaining copy of a gene of interest can be placed under CaMAL2 promoter control in a strain where the first copy has been deleted, permitting analysis of gene function by manipulation of carbon source. CIp10-MAL2p should therefore provide a useful means for functional analysis of genes in C. albicans. We have used this strategy with C. albicans DPB2 to demonstrate that the gene is essential and that loss of function leads cells to adopt a hypha-like morphology as they cease proliferation.

CCK peptides with combined features of hexa- and tetrapeptide CCK-A agonists.

Selective CCK-A agonist activity has been reported to induce satiety in a variety of animals, including man, and thereby suggests a therapeutic role for CCK in the management of obesity. To date, three general classes of CCK-A agonists have been reported, the full-length, sulfated hepta- and hexapeptides, a series of tetrapeptides, and most recently a series of benzodiazepines. The SAR of the hexa- and tetrapeptide classes suggests that the Hpa(SO(3)H) and Tac groups may not interact at the CCK-A receptor in the same location. However, the C-terminal dipeptide part of the hexapeptides and tetrapeptides appear to interact at the CCK-A receptor in a similar manner. Compound 7 (Hpa-Nle-Gly-Trp-Lys(Tac)-Asp-MePhe-NH(2)) derived from combining the features of the hexapeptides and the tetrapeptides has subnanomolar affinity and 3500-fold selectivity for CCK-A receptors. Compound 7 administered intraperitoneally produces potent, long-lasting reduction in food intake in rats and a corresponding weight loss when administered over nine consecutive days.

Harnessing the power of the genome in the search for new antibiotics.

Over the past 40 years, the search for new antibiotics has been largely restricted to well-known compound classes active against a standard set of drug targets. Although many effective compounds have been discovered, insufficient chemical variability has been generated to prevent a serious escalation in clinical resistance. Recent advances in genomics have provided an opportunity to expand the range of potential drug targets and have facilitated a fundamental shift from direct antimicrobial screening programs toward rational target-based strategies. The application of genome-based technologies such as expression profiling and proteomics will lead to further changes in the drug discovery paradigm by combining the strengths and advantages of both screening strategies in a single program.

Deletion analysis of yeast Sec65p reveals a central domain that is sufficient for function in vivo.

The Saccharomyces cerevisiae SEC65 gene encodes a 32 kDa subunit of yeast signal recognition particle that is homologous to human SRP19. Sequence comparisons suggest that the yeast protein comprises three distinct domains. The central domain (residues 98-171) exhibits substantial sequence similarity to the 144 residue SRP19. In contrast, the N-terminal and C-terminal domains (residues 1-97 and 172-273 respectively) share no similarity to SRP19, with the exception of a cluster of positively charged residues at the extreme C-terminus of both proteins. Here, we report the cloning of a Sec65p homologue from the yeast Candida albicans that shares the same extended domain structure as its S. cerevisiae counterpart. This conservation of sequence is reflected at the functional level, as the C. albicans gene can complement the conditional lethal sec65-1 mutation in S. cerevisiae. In order to examine the role of the N- and C- terminal domains in Sec65p function, we have engineered truncation mutants of S. cerevisiae SEC65 and tested these for complementing activity in vivo and for SRP integrity in vitro. These studies indicate that a minimal Sec65p comprising residues 76-209, which includes the entire central SRP19-like domain, is sufficient for SRP function in yeast.

Molecular cloning and functional analysis of the Arabidopsis thaliana DNA ligase I homologue.

A cDNA encoding the DNA ligase I homologue has been isolated from Arabidopsis thaliana using a degenerate PCR approach. The ORF of this cDNA encodes an amino acid sequence of 790 residues, representing a protein with a theoretical molecular mass of 87.8 kDa and an isoelectric point (pi) of 8.20. Alignment of the A. thaliana DNA ligase protein sequence with the sequence of DNA ligases from human (Homo sapiens), murine (Mus musculus), clawed toad (Xenopus laevis) and the yeasts Schizosaccharomyces pombe and Saccharomyces cerevisiae showed good sequence homology (42-45% identity, 61-66% similarity), particularly around the active site. Sequence data indicate that the Arabidopsis DNA ligase is the homologue of the animal DNA ligase I species. Functional analysis of the cDNA clone demonstrated its ability to complement the conditional lethal phenotype of an S. cerevisiae cdc9 mutant defective in DNA ligase activity, confirming that the cloned sequence encodes an active DNA ligase. The level of the DNA ligase transcript was not increased in A. thaliana seedlings in response to DNA damage induced by a period of enhanced UV-B irradiation. However, the cellular level of the DNA ligase mRNA transcript does correlate with the replicative state of plant cells.

ARL 15849: a selective CCK-A agonist with anorectic activity in the rat and dog.

Cholecystokinin octapeptide (CCK-8) and the peptide analog ARL 14294, formerly FPL 14294, [Hpa(SO3H)-Met-Gly-Trp-Met-Asp-N(Me)Phe-NH2], have been reported to induce satiety by interaction with the CCK-A receptor subtype. ARL 15849 [Hpa(SO3H)-Nle-Gly-Trp-Nle-N(Me)-Asp-Phe-NH2] is an improved ARL 14294 analog with enhanced CCK-A receptor selectivity, greater stability, and a longer duration of action. The affinity of ARL 15849 for the CCK-A receptor (Ki = 0.034 nM) is 6,600 fold greater than for the CCK-B receptor (Ki = 224 nM), whereas CCK-8 and ARL 14294 are nonselective. Although comparable in potency to contract isolated gallbladder and induce pancreatic phosphatidylinositol hydrolysis, ARL 15849 is 3- and 100-fold more potent than ARL 14294 and CCK-8, respectively, to inhibit 3-h feeding in rats. The duration of feeding inhibition was significantly longer for ARL 15849 (>5 h), compared to equipotent doses of ARL 14294 (3 h), and CCK-8 (1 h). Intranasal administration of ARL 15849 inhibits feeding in beagle dogs with a greater separation between doses that induce emesis and those that inhibit feeding. Therefore, ARL 15849 is a potent, selective, intranasally active anorectic agent which may be useful in the treatment of eating disorders.

Synthesis and biological evaluation of potent, selective, hexapeptide CCK-A agonist anorectic agents.

Cholecystokinin (CCK) is a 33-amino acid peptide with multiple functions in both the central nervous system (via CCK-B receptors) and the periphery (via CCK-A receptors). CCK mediation of satiety via the A-receptor subtype suggest a role for CCK in the management of obesity. The carboxy terminal octapeptide (CCK-8) is fully active in this regard, but is lacking in receptor selectivity, metabolic stability, and oral bioavailability. Inversion of the chirality of Asp7 in conjunction with N-methylation of Phe8 produces compound 5 which exhibits high affinity and 2100-fold selectivity for CCK-A receptors. Compound 6 (Hpa(SO3H)-Nle-Gly-Trp-Nle-MeAsp-Phe-NH2), derived from moving the N-methyl group from Phe to Asp, decreased CCK-B affinity substantially without affecting CCK-A affinity, giving a compound with 6600-fold selectivity for CCK-A receptors. These compounds inhibit food intake with nanomolar potency following intraperitoneal administration in fasted rats. In addition to greater potency, compound 6 produces weight loss in rats when administered over nine consecutive days. Intranasal administration of 6 potently inhibits feeding in beagle dogs. Compound 6 produces potent anorectic activity via the CCK-A receptor system.

Isolation and molecular characterisation of the POL3 gene from Candida albicans.

In Saccharomyces cerevisiae, the CDC2 gene encodes the large subunit of DNA polymerase III, the analogue of mammalian DNA polymerase delta. We have isolated DNA fragments from a library of Candida albicans genomic DNA in the vector pRS316 that rescue temperature sensitive cdc2 mutations in S. cerevisiae. These fragments contain an ORF coding for a protein of 1038 aa with a predicted molecular mass of 118.8 kDa. The predicted protein shows homology to a number of eukaryotic DNA polymerases, with 62% identity over its length to the S. cerevisiae Cdc2 protein. It also contains a number of motifs which are characteristic of DNA polymerases in general and viral polymerases in particular, as well as the conserved motif which interacts with proliferating cell nuclear antigen. These results indicate that this gene is C. albicans POL3. Analysis of the expression of C. albicans POL3 revealed that the transcript is present throughout the mitotic cell cycle, which contrasts with the expression of S. cerevisiae CDC2.

Molecular cloning and analysis of CDC28 and cyclin homologues from the human fungal pathogen Candida albicans.

In the budding yeast Saccharomyces cerevisiae, progress of the cell cycle beyond the major control point in G1 phase, termed START, requires activation of the evolutionarily conserved Cdc28 protein kinase by direct association with G1 cyclins. We have used a conditional lethal mutation in CDC28 of S. cerevisiae to clone a functional homologue from the human fungal pathogen Candida albicans. The protein sequence, deduced from the nucleotide sequence, is 79% identical to that of S. cerevisiae Cdc28 and as such is the most closely related protein yet identified. We have also isolated from C. albicans two genes encoding putative G1 cyclins, by their ability to rescue a conditional G1 cyclin defect in S. cerevisiae; one of these genes encodes a protein of 697 amino acids and is identical to the product of the previously described CCN1 gene. The second gene codes for a protein of 465 residues, which has significant homology to S. cerevisiae Cln3. These data suggest that the events and regulatory mechanisms operating at START are highly conserved between these two organisms.

The complete cDNA derived sequence of the rat prolyl 4-hydroxylase alpha subunit.

A rat cDNA encoding the prolyl 4-hydroxylase alpha subunit (P4H alpha) was isolated and sequenced. The primary aa sequence deduced from the nucleotide sequence reveals a 534-aa protein that shows extensive aa identity with the human (88%) and chick (77%) P4H alpha.

FPL 14294: a novel CCK-8 agonist with potent intranasal anorectic activity in the rat.

Cholecystokinin octapeptide (CCK-8) induces satiety in many species including man. However, its therapeutic utility is restricted due to its short biological half-life and poor bioavailability. FPL 14294 [4-(sulfoxy)-phenylacetyl(MePhe6)CCK-6] is a CCK analog with enhanced metabolic stability that was comparable to CCK-8 in potency to contract isolated gallbladder and in affinity at the CCK-A and CCK-B receptor. However, FPL 14294 was more than 200 times more potent than CCK-8 in inhibiting 3-h feeding in 21-h fasted rats. FPL 14294 also possessed intranasal anorectic activity at 5 micrograms/kg, while CCK-8 was inactive at doses up to 500 micrograms/kg. Anorectic activity was inhibited by pretreatment with a CCK-A antagonist (MK-329) but not by a CCK-B antagonist (L365,260). The anorectic effects of CCK-8 and FPL 14294 were the result of a direct effect on feeding and not caused indirectly by effects on water intake. These results indicate that FPL 14294 is a potent, intranasally active, anorectic agent whose enhanced in vivo potency over that of CCK-8 may reflect differences in stability, bioavailability, or receptor kinetics.

Starting to cycle: G1 controls regulating cell division in budding yeast.

In Saccharomyces cerevisiae, START has been shown to comprise a series of tightly regulated reactions by which the cellular environment is assessed and under appropriate conditions, cells are commited to a further round of mitotic division. The key effector of START is the product of the CDC28 gene and the mechanisms by which the protein kinase activity of this gene product is regulated at START are well characterized. This is in contrast to the events which follow p34CDC28 activation and the way in which progress to S phase is achieved, which are less clear. We suggest two possible models to describe the regulation of these events. Firstly, it is conceivable that the only post-START targets of the p34CDC28/G1 cyclin kinase complex are components of the SBF and DSC1 transcription factors. This would require that either SBF or DSC1 regulates CDC4 function either directly by activating the transcription of CDC4 itself or else indirectly by activating the transcription of a mediator of CDC4 function in a manner analogous to the way in which the control of CDC7 function may be mediated by transcriptional regulation of DBF4 (Jackson et al., 1993). Potential regulatory effectors of CDC4 function include SCM4, which suppresses cdc4 mutations in an allele-specific manner (Smith et al., 1992) or its homologue HFS1 (J. Hartley & J. Rosamond, unpublished). This possibility is supported by the finding that CDC4 has no upstream SCB or MCB elements, whereas SCM4 and HFS1 have either an exact or close match to the SCB. This model would further require that genes needed for bud emergence and spindle pole body duplication are also subject to transcriptional regulation by DSC1 or SBF. An alternative model is that the p34CDC28/G1 cyclin complexes have several targets post-START, one being DSC1 and the others being as yet unidentified components of the pathways leading to CDC4 function, spindle pole body duplication and bud emergence. This model could account for the functional redundancy observed amongst the G1 cyclins with the various cyclins providing substrate specificity for the kinase complex. We suggest that a complex containing Cln3 protein is primarily responsible for, and acts most efficiently on, the targets containing Swi6 protein (SBF and DSC1), with complexes containing other G1 cyclins (Cln1 and/or Cln2 proteins) principally involved in activating the other pathways. However, there must be overlap in the function of these complexes with each cyclin able to substitute for some or all of the functions when necessary, albeit with differing efficiencies. This hypothesis is supported by several observations.(ABSTRACT TRUNCATED AT 400 WORDS)

Cell cycle regulation of the yeast Cdc7 protein kinase by association with the Dbf4 protein.

Yeast Cdc7 protein kinase and Dbf4 protein are both required for the initiation of DNA replication at the G1/S phase boundary of the mitotic cell cycle. Cdc7 kinase function is stage-specific in the cell cycle, but total Cdc7 protein levels remained unchanged. Therefore, regulation of Cdc7 function appears to be the result of posttranslational modification. In this study, we have attempted to elucidate the mechanism responsible for achieving this specific execution point of Cdc7. Cdc7 kinase activity was shown to be maximal at the G1/S boundary by using either cultures synchronized with alpha factor or Cdc- mutants or with inhibitors of DNA synthesis or mitosis. Therefore, Cdc7 kinase is regulated by a posttranslational mechanism that ensures maximal Cdc7 activity at the G1/S boundary, which is consistent with Cdc7 function in the cell cycle. This cell cycle-dependent regulation could be the result of association with the Dbf4 protein. In this study, the Dbf4 protein was shown to be required for Cdc7 kinase activity in that Cdc7 kinase activity is thermolabile in vitro when extracts prepared from a temperature-sensitive dbf4 mutant grown under permissive conditions are used. In vitro reconstitution assays, in addition to employment of the two-hybrid system for protein-protein interactions, have demonstrated that the Cdc7 and Dbf4 proteins interact both in vitro and in vivo. A suppressor mutation, bob1-1, which can bypass deletion mutations in both cdc7 and dbf4 was isolated. However, the bob1-1 mutation cannot bypass all events in G1 phase because it fails to suppress temperature-sensitive cdc4 or cdc28 mutations. This indicates that the Cdc7 and Dbf4 proteins act at a common point in the cell cycle. Therefore, because of the common point of function for the two proteins and the fact that the Dbf4 protein is essential for Cdc7 function, we propose that Dbf4 may represent a cyclin-like molecule specific for the activation of Cdc7 kinase.

SCM4, a gene that suppresses mutant cdc4 function in budding yeast.

The gene SCM4 encodes a protein which suppresses a temperature-sensitive allele of the cell division cycle gene CDC4 in Saccharomyces cerevisiae. SCM4 was cloned on a 1.8 kb BamHI fragment of yeast genomic DNA in the high copy-number vector pJDB207, which results in a 50- to 100-fold increase in the level of the 700 nucleotide SCM4 transcript in vivo. The SCM4 gene encodes a 20.2 kDa protein of 187 amino-acids with a clear tripartite domain structure in which a region rich in charged residues separates two domains of largely uncharged amino acids. Although the apparent allele specificity of cdc4 suppression suggests that the CDC4 and SCM4 proteins interact, disruption of SCM4 demonstrates that the gene product is not essential for mitosis or meiosis; however, it may be a member of a family of related, functionally redundant proteins.

CDC7 protein kinase activity is required for mitosis and meiosis in Saccharomyces cerevisiae.

The product of the CDC7 gene of Saccharomyces cerevisiae has multiple cellular functions, being needed for the initiation of DNA synthesis during mitosis as well as for synaptonemal complex formation and commitment to recombination during meiosis. The CDC7 protein has protein kinase activity and contains the conserved residues characteristic of the protein kinase catalytic domain. To determine which of the cellular functions of CDC7 require this protein kinase activity, we have mutated some of the conserved residues within the CDC7 catalytic domain and have examined the ability of the mutant proteins to support mitosis and meiosis. The results indicate that the protein kinase activity of the CDC7 gene product is essential for its function in both mitosis and meiosis and that this activity is potentially regulated by phosphorylation of the CDC7 protein.